HPRE

Menu

Members Rides

Ariel Red Hunter#1


in
Members Rides

Welcome, Guest. Please login or register.
Did you miss your activation email?
October 30, 2014, 12:15:07 PM

Login with username, password and session length

 

Author Topic: Instability on C5  (Read 14472 times)

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Instability on C5
« on: August 16, 2010, 09:56:52 AM »
Guys I own a 2010 C5, which becomes very unstable at the rear swing arm, on speeds above 60-65 MPH. However if I crouch down chin on tank, the instability disappears only to reappear as soon as I am upright.

In my opinion this bike has serious aerodynamic issues, and mechanical instability at the rear swing arm. Does anybody know of any corrective measures being taken by RE to address this issue.

I am afraid to say this, but this bike is not road worthy at high speeds.  >:(

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #1 on: August 16, 2010, 10:33:53 AM »
This has been a complaint for a few - and it just about ALL comes down to proper chassis set up. The bike was designed with razor-edge geometry to be a CRISP handler and any deviation from perfect will induce a high speed oscillation. Take the bike back to your dealer and have him check the wheel alignment, tire pressure, head bearings and the set the angle of the bars as low as they will go and the problem that you experienced will most likely go away.
Spare the pig iron - spoil the part!

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #2 on: August 16, 2010, 11:06:53 AM »
Whatever may be the changes RE made to the rear swing arm of this bike, I don't care. I don't want a rajor sharp CRISP handling bike, that can't even use the entire power range available from its engine.

All I want is a bike that is stable and balanced, and not one that shakes as if some kicked her in the back.

I would go on to say so much so, that if I could plant this engine on my old frame, I can beat a "factory balanced, aligned and the works" new chassis with my old one. No matter how "Crisp" she may handle.
« Last Edit: August 16, 2010, 11:10:12 AM by BRADEY »

qgolden

  • Grease Monkey
  • ****
  • Posts: 303
  • Karma: 0
  • It takes a villiage to raise an idiot.....
Re: Instability on C5
« Reply #3 on: August 16, 2010, 12:33:53 PM »
Bradey
I think Scooterbob was saying that there is a more than likely chance that something is out of spec on the Bike Chassis, that is giving you the issues.

Mine, and most of the C5's here handle  safely alone the recommended speeds range.  Bearing in mind it is a light bike and depending on the size and shape of the operator, handling at higher speeds will vary from rider to rider.   These Bikes are not marketed and sold as high speed machines, and have a maximum top end of around 85 to 90 I do not think you would ever see an RE as an 80 MPH Canyon runner without serious modification.

Get it back to the dealer and explain your issue, and request that he test ride it. Something is out of whack and needs to be fixed. The bike as designed is very stable at 65 MPH.
Any other Enfields in New England?

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #4 on: August 16, 2010, 01:41:18 PM »
Bradey
I think Scooterbob was saying that there is a more than likely chance that something is out of spec on the Bike Chassis, that is giving you the issues.

Mine, and most of the C5's here handle  safely alone the recommended speeds range.  Bearing in mind it is a light bike and depending on the size and shape of the operator, handling at higher speeds will vary from rider to rider.   These Bikes are not marketed and sold as high speed machines, and have a maximum top end of around 85 to 90 I do not think you would ever see an RE as an 80 MPH Canyon runner without serious modification.

Get it back to the dealer and explain your issue, and request that he test ride it. Something is out of whack and needs to be fixed. The bike as designed is very stable at 65 MPH.

You are right here - although the C5 is quite the departure from the "traditional" pick your nose with one hand and steer around the potholes with the other RE handling. Perhaps a G5 would have been the better choice for Bradly as it retains the steering geometry of the Classic Bullet. That machine was built for TOTAL stability - even when overloaded. It's the "truck of choice" in lot of parts of India just because of that fact.
Spare the pig iron - spoil the part!

Sub

  • Bob's Your Uncle
  • Grease Monkey
  • ****
  • Posts: 436
  • Karma: 0
  • 2010 Black Bullet C5
Re: Instability on C5
« Reply #5 on: August 16, 2010, 03:52:27 PM »
I think what you're experiencing is normal. I did 65 for the first time the other day and a brief wiggle of the bars created an unnerving oscillation. :) The bike is just not designed for it, and I'm ok with that. If I need to do highway, I'll take another ride.

Frankly, if it were good, it would lose some of the charm and character this bike possesses. To be honest, character is the main reason I bought this bike.  I dont think anyone at RE expects this bike to be a high speed demon or even able to keep up with modern bikes. However, on a back road, doing 50 through twisties, it is quite capable.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #6 on: August 16, 2010, 05:02:34 PM »
Here is an interesting link describing motorcycle chassis oscillation. Note that EVERY motorcycle has a resonant chassic frequency!

http://www.vf750fd.com/blurbs/vibmode.html
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #7 on: August 16, 2010, 05:08:37 PM »
Come on now Guy's, that's a little bit of Monday morning Quarter backing , for those of us who are having this issue.And it seems not all are. And in all fairness, last year they did market the new UCE with higher speeds. Definitely a deciding factor as to why I bought it.I wish I had bought the G-5. The dealer did not put me on a scale, and measure my height, then say, " Ya know what, Ya better get the G-5  if your ever gonna get on the highway and do some real world riding". And I'm not even sure it has anything to do with weight or height.This is a bike being marketed in the U.S. with all our major highways. Maybe there's  bad batch of frames out there?I don't yet Know for sure what it is.
 Remember, Before  my swing arm mod, with the bike aligned correctly, 18" front wheel, Head bearings adjusted correctly, all motor mount fasteners, all fasteners checked, tire pressure, etc, etc. A bone stock bike, I started loosing stability at 60 mph.
    I consulted with my dealer,who is no longer a dealer, and head mechanic, who had no Idea and gave me the honest answer that he had only worked on RE's for two years. My other option is to take it to the next closest dealer witch is 6 hrs of traffic hell round trip. To be likely told "everthing looks fine".Look, I ain't an RE expert but as scotty so kindly put it, I ain't no slouch.Something is amiss.And as you guy's know, I have gone above and beyond the average guy and been pretty positive about it.
  Look, I think one of the reasons guy's like Brady and me are on this forum is because it is are most accessable link to the company and the experts. Also the people with vast knowledge on these bikes. All great people and also a deciding factor in purchasing this bike.You know I heard comments from people, not here,that the C-5 is just "an old Mans bike" and " is really just for cruising around on back country roads". B.S.!!!!
  So lets figure this out. What are our options. Sell the bike to the next unsuspecting soul? Trade it in for a G-5? Sorry, I like you ,work hard for my money and am not willing to take a Loss on a sale or a trade.
 Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #8 on: August 16, 2010, 05:19:16 PM »
Here is an interesting link describing motorcycle chassis oscillation. Note that EVERY motorcycle has a resonant chassic frequency!

http://www.vf750fd.com/blurbs/vibmode.html
Interesting link, thanks Bob.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #9 on: August 16, 2010, 05:51:29 PM »
Here we have the proper recovery technique for a gentle high speed oscillation. Notice the rider gets out of the saddle to add weight to the front suspension to settle the oscillation. Next, he shifts his weight to the right side of the bike to counter the weave - and then pops back into the saddle to motor off happily!

http://www.youtube.com/watch?v=6Fa0GmdSN4A&NR=1

Enjoy!
Spare the pig iron - spoil the part!

CMB

  • Neophyte
  • *
  • Posts: 33
  • Karma: 0
Re: Instability on C5
« Reply #10 on: August 16, 2010, 06:18:09 PM »
Dan,

I'm with you. Luckily my local dealer has a C5 demo bike that I was able to ride on the freeways out here in Southern California. Once I hit 60 and the rain-grooves the front end started shaking - and then the rear started oscillating too. Back-off to 55 and everthing is fine.

I would love to own a C5. Given the choice of looks and remaining alive, I'll take the G5.

I hope you can get things sorted out with yours. My dealer thinks the fork bracket will work.

Cameron

perri

  • Neophyte
  • *
  • Posts: 40
  • Karma: 0
  • Italy
Re: Instability on C5
« Reply #11 on: August 16, 2010, 06:38:04 PM »
I write from italy, c5 are the owner of 2009, confirm the earlier instability

sorry for bad english
c5 2009 italy

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #12 on: August 16, 2010, 07:04:30 PM »
Thanks Cameron, I hope it works, I'm running out of options. Same experience here with my bike, minus the rain grooves. Starting to see a pattern? India, U.S. Italy. Maybe we all need video riding lessons? ::)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

TheFatMan

  • Scooter
  • **
  • Posts: 56
  • Karma: 0
  • The Fat Man's home on the lake
Re: Instability on C5
« Reply #13 on: August 16, 2010, 09:44:41 PM »
You guys are making me nervous.  I am 5'10 and 230# (the fat man).  I have not encountered this resonant wobble at any speed, but haven't beat 65mph yet.  Is this on all of em?

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #14 on: August 16, 2010, 10:12:52 PM »
I've never experienced it on mine either, I wouldn't worry about it.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #15 on: August 17, 2010, 12:03:30 AM »
You guys are making me nervous.  I am 5'10 and 230# (the fat man).  I have not encountered this resonant wobble at any speed, but haven't beat 65mph yet.  Is this on all of em?
  Don't be nervious, I don't think its on all the bikes. At least from what I've read. No one is trying to scare anbody. Just trying to find a solution, for the guys that are having it. If you had the problem Fatman, it's unmistakable and you would know.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #16 on: August 17, 2010, 01:45:59 AM »
Thanks Cameron, I hope it works, I'm running out of options. Same experience here with my bike, minus the rain grooves. Starting to see a pattern? India, U.S. Italy. Maybe we all need video riding lessons? ::)

Dan, Cameron and BRADEY:

Hope that your bikes get fixed for excessive vibrations and instability at speeds above 60-65 mph.  It is not an issue that should be taken lightly or dismissed with a disdain simply because some riders have not experienced it.  EVERY rider and EVERY bike should be treated as important.  It is quite clear that you just want a solution or a way of communication to the manufacturer through the dealer or via the importer.

Even though some here in US or other countries may buy RE for its charm and its quirks and opt to use a second or third bike for high speeds, but in India this may be the ONLY bike of the owner.  He or She will ride it at 60 to 65 mph on highway.  Secondly, not many riders use RE in US as their main mode of transportation, but in India this may be their only or main mode of travel.  These new UCE C5 bikes are touted as highway capable, so they better be.
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #17 on: August 17, 2010, 01:57:40 AM »
Well put brother sing. When I get this sorted, we are gonna hop on RT 80, 78 or 287, to get to those beutifull country roads ,out west Jersey. ;)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #18 on: August 17, 2010, 02:03:32 AM »
Well put brother sing. When I get this sorted, we are gonna hop on RT 80, 78 or 287, to get to those beutifull country roads ,out west Jersey. ;)

I look forward to see you and take our bikes on the beautiful back roads of Hunterdon and Somerset counties of New Jersey  :).
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

qgolden

  • Grease Monkey
  • ****
  • Posts: 303
  • Karma: 0
  • It takes a villiage to raise an idiot.....
Re: Instability on C5
« Reply #19 on: August 17, 2010, 04:14:50 AM »
Dan, et al.
If I in any way diminished, downplayed or made light of your issues or the documented issues of stability that has been noted by others then I very humbly apologize.  That was not my intention.

I admire your work, enjoy offering suggestions to solving the issue and look forward to you completing your experiments, you have vast more experience at the road handling aspects of of two wheeled vehicles than I will ever have despite my having restored several bikes and riding all kinds of marques for 35 years.

My intention was to make the point that most of us casual non-stress (fair weather and sunny days) riders do not experience the high speed instability that you and a few others have seen. 

I do wholeheartedly agree that based on the number of bikes on this forum and the number of folks complaining of similar issues the statistical sampling is unacceptable.

That being said, I do feel that the issue is just far enough outside of the norm that if it exhibits itself the the first thing to do is to check and recheck the intended factory settings.  IMHO that will cure a measurable percentage of the bikes with  the issue.  Not all of them, certainly not yours.  Also bear in mind that some folks are far more sensitive to such issues.  You are an experienced canyon runner, I am not.  In my world if I were to pick instability at high speed, I would simply back off on the throttle until it subsides..  In your word, you feel it and it bothers you. It's gotta' be fixed.

Also note that there are a lot of new dealers now selling this marque.  I have little confidence that my dealer, (although a great guy to do business with) would be qualified to anticipate such an issue.  I don't know if they really know how to set up an Enfield.  I had the perception that they did not participate in any factory training at the mechanic level.  So how many bikes are exhibiting these symptoms because the inexperienced dealer does not know what to watch out for upon assembly?

Any Case I was attempting to suggest a logical starting point for the OP,  Based on what I perceived from his post he is not as experienced as you are and  I feel that anytime a handling issue raises its head then you need to start with the basics, and that is chassis, tires, bearings etc.  To most folks that should start with a trip to the dealer.

If I offended then I am sorry.
Any other Enfields in New England?

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #20 on: August 17, 2010, 06:00:04 AM »
 Cheers Quinn, all is cool. I took no offence and can appreciate your prospective. I understand and that's whats so frustrating.I look forward to your input. Thanks for the kind words.But please do not put me above anyone else here. I'm am a working class guy,and very proud of it. Like you and many others here, have spent our lives working with our hands.I know more then some,and less then some. That's all. Like it or not we are committed gearheads, problem solvers. Were the guys all the family members say" I bet Dan or Quinn or bob or scott or who ever, can fix that" or "figure that out". I did have a couple of bikes in a magazine which came out last week. Don't give me a big head :D. I worked long and hard for that.And to be perfectly honest, I don't think all of my family even knows about it yet. Why? Because right now my problem to solve is this bike.I tend to get deeply involved in my projects. I love doing this and can get very passionate.So if I came on too strong, the apologies are mine to offer.
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #21 on: August 17, 2010, 06:37:55 AM »
Thank you all guys for pouring in your thoughts. To begin with I purchased this model of RE only because the company clearly advertised it as a bike you could use for an all day cruise at 70 MPH, which I think its engine is quite capable of.

And I do not agree with people who wish to suggest that a sharp handling bike should not be stable stable on high speeds. Hell even my Vespa scooter with a much shorter wheel base and far more sharper handling is more stable than this bike.

As Singh says, this bike in India is used like a Harley to cruise long distances, and considering that I am sorry to state that RE has failed on two counts with this bike, A) Comfort, B) Instability on high speeds (which is the forte of this model, at least for Indian riding conditions). I suppose they designed it more for the US markets where this would mainly be used as a second vehicle to do trips to buy CHEESE & BREAD, or do a sedated 50 MPH on the CURVING back roads, rather than serious long distance munching (sorry if I have used too many food words here, seems I am hungry  ;D).

My earlier bike an Iron head 350 in stock condition can do 70 MPH as well. And though it tops there, but she never wobbles even though you are kicking her hard.
I prefer riding it mostly at 50 MPH which she is very capable of doing all day long.



Rusty

  • Bulleteer
  • ***
  • Posts: 117
  • Karma: 0
Re: Instability on C5
« Reply #22 on: August 17, 2010, 07:51:24 AM »
Also note that there are a lot of new dealers now selling this marque ........... I don't know if they really know how to set up an Enfield.  I had the perception that they did not participate in any factory training at the mechanic level.  So how many bikes are exhibiting these symptoms because the inexperienced dealer does not know what to watch out for upon assembly?

A good point, soon after I bought my bike I asked my dealer about the UK importers training programme, the response was that they hadn't had any training but the bikes are so simple they didn't need any. Well perhaps the C5 with its new frame is sufficiently different to warrant a bit of extra care.

As regards the instability, on my bike it happens at speeds when the engine is feeling a bit stressed so I rarely ride that fast. Those suffering at lower speeds must be struggling.

Things that I will check are the tyre pressures, swing arm bearings, the head race bearings, fork oil level, and all of the engine mounting bolts. I can’t think of anything else that would cause the bike to wobble that I could fix.

Maturin

  • Grand Gearhead
  • *****
  • Posts: 790
  • Karma: 0
  • My Precious
Re: Instability on C5
« Reply #23 on: August 17, 2010, 11:12:38 AM »
"Things that I will check are the tyre pressures, swing arm bearings, the head race bearings, fork oil level, and all of the engine mounting bolts. I can’t think of anything else that would cause the bike to wobble that I could fix".

[/quote]

..ahem...I can, Rusty  ;D
Check your wheels. Mine were beautifull, no question, but not round. The side clearance was about 3 mm, the height clearance was 1 mm what was close to protest. But since I have a G5, I don´t have much problems with stability.
Another point is the wheels balancing. I don´t think they are balanced in the factory, I never saw any weights on the bikes. I experienced some very strange effects of wrong-balanced wheels in the past.
But my odds on favorite for wobblebuilding is the fork. The C5 fork may be a bit different from the G5´s but they are mounting the same fethers and the same oil (that is probable thin enough to be replaced by one of Singhg´s stronger tea brands). There is a German Company offering improved progressive fethers (http://www.wirth-federn.de/  - time to improve your german, gentlemen  ;D). Already appointed, not yet delivered, I´ll keep you guys posted.
2010 G5
A Garage without a Bullet is a empty, barren hole.

When acellerating the tears of emotion must flow off horizontally to the ears.
Walter Röhrl

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #24 on: August 17, 2010, 12:04:18 PM »
When I was a dealer, I used to freak out over the "no wheel weights" - I started checking the front wheels before I put them on the bikes - and pulled a few random rear wheels for checking also. I found that they were ALL, without exception, DEAD NUTS perfect. Zero balance and the runout and side to side were well within acceptable for a steel wheel. The India boys can build a damn fine hoop if you ask me!

You are correct, however, in that a wheel imbalance is one of the biggest causes of attaining the frames resonant frequency - and therefore a wobble. The "noise" that I'm getting is that the frequency is about 4 to 6Hz - and that would be about wheel rotation frequency.
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #25 on: August 17, 2010, 01:30:02 PM »
Yea, I also found the same. No weights on mine. pulled the wheels and balanced them, they were off, but not much.Definitely nothing I could feel.An imbalanced wheel would likely start off at speed with a continuesly increasing shudder or vibration.This is not the feeling I'm getting with this issue, It more like the bottom falls out of your stability a high speeds, then stop, then will do it again.With a definite light feel to the front end. Leaving you wondering what the hell was that.It's probably a combination of weight and geometry, both the rider and the bike. That's why guys are feeling it at different speeds, or not at all.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #26 on: August 17, 2010, 03:11:40 PM »
Yea, I also found the same. No weights on mine. pulled the wheels and balanced them, they were off, but not much.Definitely nothing I could feel.An imbalanced wheel would likely start off at speed with a continuesly increasing shudder or vibration.This is not the feeling I'm getting with this issue, It more like the bottom falls out of your stability a high speeds, then stop, then will do it again.With a definite light feel to the front end. Leaving you wondering what the hell was that.It's probably a combination of weight and geometry, both the rider and the bike. That's why guys are feeling it at different speeds, or not at all.

Just wondering, GHG - Have you tried any different rear spring adjustments to load or unload the front end? How's the oil level in the front forks, too? I'm REALLY curious here - YOU are the only one who has, so far, attempted to DEFINE this wobble and tried to quantify it. I cannot, for the life of me, re-create this on the test junk under anywhere NEAR "normal" conditions ..... Sign me "Still Searching"
Spare the pig iron - spoil the part!

CMB

  • Neophyte
  • *
  • Posts: 33
  • Karma: 0
Re: Instability on C5
« Reply #27 on: August 17, 2010, 04:49:22 PM »
Didn't mean to scare anybody. I was just relating my experience.

Cameron
(still waiting for CARB approval so I can join the RE club)

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #28 on: August 17, 2010, 04:52:50 PM »
Just wondering, GHG - Have you tried any different rear spring adjustments to load or unload the front end? How's the oil level in the front forks, too? I'm REALLY curious here - YOU are the only one who has, so far, attempted to DEFINE this wobble and tried to quantify it. I cannot, for the life of me, re-create this on the test junk under anywhere NEAR "normal" conditions ..... Sign me "Still Searching"
Yes bob I have. up down and in the middle.I am not with the bike right now, but presently I believe it's set at center. Fork legs are now filled with 20 wt fork oil,(also have tried 10 and 15wt) to the volume in the service manual, again I don't have it with me, but if memory serves me, 200 ml's each? When I drained the stock fork oil , did not measure the volume, but they appeared full, by the amount that came out.
 Not to get off this train of thought, but while I'm thinking of it.My c-5 was one of the earlier ones over here. I believe you guys worked on it, due to the problem with the trans gears. Did not go to recall,you guys picked it up before the bikes went out.Did a good job it appears by all of the fastener paint. Is it possible that these motors have shims, or a motor plate missing or misaligned?Throttle responce is also a factor with this oscillation, or can induce it. And, no I'm not finger tipping the bars on the highway.Just trying to rule all out.
Thanks bob, Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #29 on: August 17, 2010, 06:52:29 PM »
Here is an interesting link describing motorcycle chassis oscillation. Note that EVERY motorcycle has a resonant chassic frequency!

http://www.vf750fd.com/blurbs/vibmode.html
Excellent read. Gonna need the professor to sort out that Chinese arithmetic though. :D
So if a duck floats and so does wood, she must be a witch? :D Sorry I could not help myself. r80rt ;)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #30 on: August 17, 2010, 07:02:42 PM »
Who are you, who are so wise in the ways of science?
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #31 on: August 17, 2010, 08:57:00 PM »
I am Arthur, King of the Brittons .Oh Geez,too funny. we better stop before they kick us off.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #32 on: August 17, 2010, 09:00:23 PM »
Yes bob I have. up down and in the middle.I am not with the bike right now, but presently I believe it's set at center. Fork legs are now filled with 20 wt fork oil,(also have tried 10 and 15wt) to the volume in the service manual, again I don't have it with me, but if memory serves me, 200 ml's each? When I drained the stock fork oil , did not measure the volume, but they appeared full, by the amount that came out.
 Not to get off this train of thought, but while I'm thinking of it.My c-5 was one of the earlier ones over here. I believe you guys worked on it, due to the problem with the trans gears. Did not go to recall,you guys picked it up before the bikes went out.Did a good job it appears by all of the fastener paint. Is it possible that these motors have shims, or a motor plate missing or misaligned?Throttle responce is also a factor with this oscillation, or can induce it. And, no I'm not finger tipping the bars on the highway.Just trying to rule all out.
Thanks bob, Dan.

Dan - Interesting that you should mention the motor ..... As a stressed member of the frame, it must be able to absorb (dampen) any resonant vibrations in the frame. The frame, likewise, takes a bit of shake out of the motor by dissipating it in the frame. That being said - have you loosened the mounts so they'll just move and started the bike - or even ridden it a little bit to allow frame stresses to normalise in the bike? Re-tighten the bolts with someone sitting on the bike, holding it up level. We took all the engines out of the bikes with them firmly bolted down by the suspension to eliminate ALL the problems that would normally be caused by the frame flexing and moving around with the biggest single stressed member removed. This does not, however, preclude ALL movement of the "bits and pieces" as sometimes, from the Factory, they were under a bit of stress. There is nothing to align or shim at all - the assemble is brutally, wonderfully simple - but - if the frame has a slight torsional stress on it - it COULD, conceivably, create an oscillation at speeds in trying to "find center" again. The frames on these bikes are amazingly springy - they are probably made from some serious good steel. IF there was some stress in the frame (usually manifests itself as some hella handlebar vibration ....) it WOULD be trying to spring back - and may get you wobblin' ...... Just a thought.
Spare the pig iron - spoil the part!

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #33 on: August 17, 2010, 10:33:36 PM »
That little trick will sure smooth out a 500 BSA!
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #34 on: August 17, 2010, 11:10:29 PM »
That little trick will sure smooth out a 500 BSA!
Ya know as i was reading bobs reply, that thought popped into my head, the old bsa trick. Sh@! it's wortha try! Bob no I have not tried it,but will now. I will let you know.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #35 on: August 18, 2010, 03:03:26 AM »
I've never done it but it was standard practice with British bikes in the old days.  Break the engine in a little, loosen, sit, tighten.  Forgot all about that!  I want to do it just for giggles now.

Scott

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #36 on: August 18, 2010, 03:53:35 AM »
Ya know as i was reading bobs reply, that thought popped into my head, the old bsa trick. Sh@! it's wortha try! Bob no I have not tried it,but will now.

Yes bob I have. up down and in the middle.I am not with the bike right now, but presently I believe it's set at center.  

Fork legs are now filled with 20 wt fork oil,(also have tried 10 and 15wt) to the volume in the service manual..

Is it possible that these motors have shims, or a motor plate missing or misaligned?

Throttle responce is also a factor with this oscillation, or can induce it. And, no I'm not finger tipping the bars on the highway.Just trying to rule all out.
Thanks bob, Dan.

Dan:

Looks like the thread is moving forward in a positive direction.  To help it along, how about if you list the things you have tried and what was the result.  Also list the ideas  or any thought that you  have not tried yet.

Based upon what I have read in the thread I have compiled the list below.  By eliminating one by one, you may find the source of problem.  Add more as you keep up with your search.

1. Rear shock adjustment - Tried, but no improvement.

2.  Wheels balanced - Tried, but no improvment.

3.  Fork oil replaced with different weight - Tried, but no improvement.

4. Old BSA trick -  Not tried yet.

5.  Throttle can induce vibrations -  If old BSA trick does not fix it, then the interior of the engine may need further investigation.  

6.  Just to rule out - wheel alignment and typre pressure ??

7.  Swing arm bush ?

8.  Steering Head bearings ??
« Last Edit: August 18, 2010, 04:15:26 AM by singhg5 »
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Re: Instability on C5
« Reply #37 on: August 18, 2010, 06:41:27 AM »
Things I have tried with no effect on improvement;

Rear shock adjustment
Wheel balancing
Old BSA trick which had effect only on vibrations and reduced it around 60% But no effect on instability. Which makes me think its not the vibrations but the swing arm/suspension related.

When it improved
 
Reducing rear tyre pressure to 27-28 Psi
Rear wheel alignment
Placing a shim between the hub and brake assembly

Things I have planned to try;

Changing rear shock absorbers to oil filled ones or some other make gas shocks.
Changing the swing arm plastic bushes to the rubber/iron bushes from CI bullet.
Strengthening the swing arm at the pivot joint and a bit further downwards


BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #38 on: August 18, 2010, 08:43:12 AM »
I am meeting the company's engineer tomorrow to get this issue of instability out of my life. Guys I only know how to ride a motorcycle, but have little or no experience setting one up correctly. Could you please suggest the areas I should ask him to look into. Please respond at the earliest.

cheers.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #39 on: August 18, 2010, 11:54:23 AM »
Ya know as i was reading bobs reply, that thought popped into my head, the old bsa trick. Sh@! it's wortha try! Bob no I have not tried it,but will now. I will let you know.

Keep in mind that this is not necessarily to quell the high frequency, fourth order engine vibration - although it WILL - this is to remove any potential "spring" (kinetic) energy from the frame that would manifest itself at say - 4 to 8Hz - the frequency of the wobble. Remember that the frames are of GOOD steel on these and they WANT to be straight ... a little stress about the engine could store the needed energy to make 'er shake. Let me know, eh?
Spare the pig iron - spoil the part!

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #40 on: August 18, 2010, 11:57:55 AM »
I am meeting the company's engineer tomorrow to get this issue of instability out of my life. Guys I only know how to ride a motorcycle, but have little or no experience setting one up correctly. Could you please suggest the areas I should ask him to look into. Please respond at the earliest.

cheers.

Check wheel alignment, tyre pressure, suspension pre-loading and forl oil viscosity and level for YOUR weight. Check also the frame stress as previously posted - and do set the bars as low as they will go without banging the tank. Be sure that the engineers check the VERTICAL alignment of the wheels as well - especially the rer one. Let us know what they find.
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #41 on: August 18, 2010, 03:03:55 PM »
Dan:

Looks like the thread is moving forward in a positive direction.  To help it along, how about if you list the things you have tried and what was the result.  Also list the ideas  or any thought that you  have not tried yet.

Based upon what I have read in the thread I have compiled the list below.  By eliminating one by one, you may find the source of problem.  Add more as you keep up with your search.

1. Rear shock adjustment - Tried, but no improvement.

2.  Wheels balanced - Tried, but no improvment.

3.  Fork oil replaced with different weight - Tried, but no improvement.

4. Old BSA trick -  Not tried yet.

5.  Throttle can induce vibrations -  If old BSA trick does not fix it, then the interior of the engine may need further investigation.  

6.  Just to rule out - wheel alignment and typre pressure ??

7.  Swing arm bush ?

8.  Steering Head bearings ??
Yes Sing, all tried, except BSA trick, tonight though. Add wheel truing, bearing inspection, Braced swing arm, 19" front wheel, Steering stabilizer and caged fork brace under front fender.Check my other threads, I know it's a bit of a tangent. And let me add, the swing arm bushing are not bad on these bikes, there is no excess movement in the pivot area.I think that putting rubber bushings would only add to the flex in the very long and unsupported C-5 swing arm. I do believe that the G-5 has a shorter swing arm.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #42 on: August 18, 2010, 04:40:33 PM »
Sing, sorry but also add wider handle bars,33", in an attempt to reigh in the bike at speed. I'll let you know about Labor day.
Thanks Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #43 on: August 19, 2010, 05:22:34 AM »
Bradey, check out our findings under my thread, steering damper for C-5. See what the engineer thinks about the loading and unloading of the rear chassis.
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #44 on: August 19, 2010, 04:45:57 PM »
You've gotten more erudite suggestions than I could give, but I was thinking going to the 19" front hoop might improve stability as well. Change the steering geometry.

FWIW, my C5 has had no problems.  I am routinely up to 70, and have gone higher. I can MAKE it oscillate, but it doesn't do it of it's own accord. Got to be something off in the setup.  Good luck!

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #45 on: August 19, 2010, 04:48:48 PM »
You've gotten more erudite suggestions than I could give, but I was thinking going to the 19" front hoop might improve stability as well. Change the steering geometry.

FWIW, my C5 has had no problems.  I am routinely up to 70, and have gone higher. I can MAKE it oscillate, but it doesn't do it of it's own accord. Got to be something off in the setup.  Good luck!

I'm curious here - if you "upset" the bike in a straight line - how many oscillations do you get 'til it's fine again. Mine will do about two - and that's all in the gyroscopic procession, I believe - not in the suspension at all .......
Spare the pig iron - spoil the part!

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #46 on: August 19, 2010, 05:02:29 PM »
hmmmm....2-3 I think.  It's been awhile since I've experienced it. It self corrects pretty quickly, and I've had it up better than 85mph. It's a twitchy bike, fer sure, but mines not "unstable" like some.

Oh...and I just read throught the other thread and saw he has the 19" already (told ya I didn't know much...)

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #47 on: August 19, 2010, 05:14:56 PM »
hmmmm....2-3 I think.  It's been awhile since I've experienced it. It self corrects pretty quickly, and I've had it up better than 85mph. It's a twitchy bike, fer sure, but mines not "unstable" like some.

Oh...and I just read throught the other thread and saw he has the 19" already (told ya I didn't know much...)

That sounds about right ..... I call the handling "crisp" - it sure does where you tell it to go .... especially at speeds, but it's not as hard to control near the edge of sanity like the Ducati. Slip up on THAT bike and you are going to fall off ...... period. The Enfield will give you a chance to recant your testimony once .... Hahaha!
Spare the pig iron - spoil the part!

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #48 on: August 19, 2010, 05:57:49 PM »
Never been on a Duc....sounds like handful!

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #49 on: August 19, 2010, 06:01:58 PM »
Never been on a Duc....sounds like handful!

Well - they are essentially race bikes with turn signals .... YOU have to be in charge of them - or you WILL get tossed. That's why I ride the Enfield the most! Hahaha! I'm too old to fall off hard - I'd shatter like a china plate on a tile floor ......  ;)
Spare the pig iron - spoil the part!

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #50 on: August 19, 2010, 06:03:29 PM »
LOL!!  Too much bike for me.  I like riding slow bikes fast, but riding fast bikes fast sounds like a good way for me to get in trouble.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #51 on: August 19, 2010, 06:03:47 PM »
GHG - I just had a brainstorm ...... Is your rear, drive side bearing going away on the wheel? Give it a good tug, top and bottom to check this ..... Lemme know!
Spare the pig iron - spoil the part!

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #52 on: August 19, 2010, 06:08:26 PM »
LOL!!  Too much bike for me.  I like riding slow bikes fast, but riding fast bikes fast sounds like a good way for me to get in trouble.

Well - I usually suit up and take it out about twice a year - once to remind me why I bought it (better than sex!) and once to remind me why I shouldn't ride it (STILL better than sex ....!) It's not FURIOUSLY fast like a one liter Japper-Knees bike with all them extra "syllables" - but the handling is crisp enough to make your ears bleed .... and that WILL get you in trouble on the street. Rocks, other cars, small dogs and kids will ALL upset the chassis right at the edge of traction .... They ain't none of that stuff on the racetrack, where that heep belongs! Hahaha!
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #53 on: August 20, 2010, 02:36:28 AM »
You've gotten more erudite suggestions than I could give, but I was thinking going to the 19" front hoop might improve stability as well. Change the steering geometry.

FWIW, my C5 has had no problems.  I am routinely up to 70, and have gone higher. I can MAKE it oscillate, but it doesn't do it of it's own accord. Got to be something off in the setup.  Good luck!

 Another Rocker with a C-5?, Thanks man. Have you tried the ton on yours?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #54 on: August 20, 2010, 12:41:05 PM »
The visiting RE engineer had the entire rear suspension dismantlled, including the rear wheel, hub and the front sprocket. He found the wear pattern on both sprocs equal and hence they were put back as before. He then checked the spacer of the rear wheel and decided to change it, as also the spacer in the swing arm. Refiited everything back and I tested the bike till 130 KPH/81 MPH. It was stable, in fact I did try to weave it at those speed, but it did not oscillate. ;D
Now for the tricky part (what the engineer did not know). The attending mechanic unknowingly added few shims on either sides of the rear shockers (upper bolts), cause he thought the gap was too big for the bolts to hold it tightly.
If you guys know, the Indian version comes with a seat pre installed which slots with the fastners where the rear suspension goes and its front is bolted the fram below the front seat. My two cents, the removal of the rear seat created a gap at the rear upper bolts which allowed the rear supension space to pull on either sides, creating the oscillation. I also saw the upper bushes of the shockers pulled sideways. Let me know if this theory holds any water.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #55 on: August 20, 2010, 12:50:38 PM »
Good for you, glad you got an answer! I checked my C5 and did see a gap at the top of the shocks. I haven't had any problem but I put a washer in there to take up the slack any way. Thanks!
« Last Edit: August 20, 2010, 01:39:01 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #56 on: August 20, 2010, 02:01:23 PM »
WOW!!! EXCELENT!!!.  Still trying to disifer what he's saying though? r80rt, I think he means you should not have to put in the washers? What side wheel spacer did he change? To what size? What swing arm Spacer?  What the? Oh Geez, i'm not here with my bike!  Please someone!!!  Bradey your kill'in me, more detail Please!!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #57 on: August 20, 2010, 02:05:19 PM »
I just went for a short blast up to 70mph, if the washers did anything I didn't notice it.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #58 on: August 20, 2010, 02:21:21 PM »

 Another Rocker with a C-5?, Thanks man. Have you tried the ton on yours?

Yeah man!  I got her up to 95 mph once (on the dial anyway...)...WOT, laid down on the tank, feet on the rear pegs...scared the crap outta myself on this bike.  I swear, there was a bit more to spare and I ditched the old pipe since, so I have to try it again.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #59 on: August 20, 2010, 02:24:44 PM »
WOW!!! EXCELENT!!!.  Still trying to disifer what he's saying though? r80rt, I think he means you should not have to put in the washers? What side wheel spacer did he change? To what size? What swing arm Spacer?  What the? Oh Geez, i'm not here with my bike!  Please someone!!!  Bradey your kill'in me, more detail Please!!

The only spacer that's in your swingarm is a tube that goes between the bushings - which are pressed into the swing arm pivot. They aren't selective - and tightening the through bolt SHOULD pull it all together ...... Same with the wheel spacers - no selection here ..... and tightening the spindle should pull it all to "zero" ..... I want to what what voodoo went on there as well ..... I'M thinkin' someone just found a loose bolt - or took apart, scratched their heads and inadvertently put it back together right ..... it's a mystery!
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #60 on: August 20, 2010, 02:33:12 PM »
 Ya, what the hell? Get on the horn bob, wake up that engineer!! Please ::)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #61 on: August 20, 2010, 04:35:34 PM »
The only spacer that's in your swingarm is a tube that goes between the bushings - which are pressed into the swing arm pivot. They aren't selective - and tightening the through bolt SHOULD pull it all together ...... Same with the wheel spacers - no selection here ..... and tightening the spindle should pull it all to "zero" ..... I want to what what voodoo went on there as well ..... I'M thinkin' someone just found a loose bolt - or took apart, scratched their heads and inadvertently put it back together right ..... it's a mystery!
Yes, definatley what I found on the swing arm, no play at all at the pivot, flex was at the rear of the swing arm.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #62 on: August 20, 2010, 04:54:09 PM »
Yes, definatley what I found on the swing arm, no play at all at the pivot, flex was at the rear of the swing arm.

I find that really odd ..... the section of the swingarm that sticks out past the triangulation of the pivot, shock bottom and shock top is pretty short - and PIG IRON .... it shouldn't flex - even when riding pretty hard. What kind of monkey motion did you get there? Lemme know. I'm QUITE curious at this point ......
Spare the pig iron - spoil the part!

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #63 on: August 20, 2010, 05:11:24 PM »
The visiting RE engineer had the entire rear suspension dismantlled, including the rear wheel, hub and the front sprocket. He found the wear pattern on both sprocs equal and hence they were put back as before. He then checked the spacer of the rear wheel and decided to change it, as also the spacer in the swing arm. Refiited everything back and I tested the bike till 130 KPH/81 MPH. It was stable, in fact I did try to weave it at those speed, but it did not oscillate. ;D

Now for the tricky part (what the engineer did not know). The attending mechanic unknowingly added few shims on either sides of the rear shockers (upper bolts), cause he thought the gap was too big for the bolts to hold it tightly.

If you guys know, the Indian version comes with a seat pre installed which slots with the fastners where the rear suspension goes and its front is bolted the fram below the front seat. My two cents, the removal of the rear seat created a gap at the rear upper bolts which allowed the rear supension space to pull on either sides, creating the oscillation. I also saw the upper bushes of the shockers pulled sideways. Let me know if this theory holds any water.


Bradey:

Time for champagne ! Glad to hear you can ride it the way it is supposed to be - Hey, you gaddaa waalaa and Hero Honda, move over for the Bullet is coming at 80 mph !  :)

Do you think it is the replacement of spacer in swing arm that solved the problem or is it the shims on the rear shocks that cured the problem ?  If you remove the shims from rear shocks, can you see if the oscillations come back ?  Or you don't want to try it and just want to enjoy the smooth ride ?
« Last Edit: August 20, 2010, 05:16:15 PM by singhg5 »
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #64 on: August 20, 2010, 05:17:43 PM »

Bradey:

Time for champagne ! Glad to hear you can ride it the way it is supposed to be - Hey, you gaddaa waalaa and Hero Honda, move over for the Bullet is coming at 80 mph !  :)

Do you think it is the replacement of spacer in swing arm that solved the problem or it is the shims on the rear shocks that cured the problem ?  If you remove the shims from rear shocks, can you see if the oscillations come back ?  Or you don't want to try it and just want to enjoy the smooth ride ?
Champagne for him, not for us quite yet. Still trying to figure out what he means?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #65 on: August 20, 2010, 05:35:16 PM »
I find that really odd ..... the section of the swingarm that sticks out past the triangulation of the pivot, shock bottom and shock top is pretty short - and PIG IRON .... it shouldn't flex - even when riding pretty hard. What kind of monkey motion did you get there? Lemme know. I'm QUITE curious at this point ......
Let me clarify, yes the axle plates and shock mount area is pretty Stout.What I mean is the week design from that point back to the pivot tube.It flexes, no gusseting or support, or arch shaped design at the pivot tube. It's basically just 3 pieces of pipe, welded in the shape of Japanese arch, Know what I mean? Like a roof on a pergala or trellis. I think it's too long for that shape, it's longer on the C-5, then on the G-5, so I read. Take one out, and push it in at the axle plates, Like Suzanne simmers does with her machine, and you'll see what I mean.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #66 on: August 20, 2010, 05:39:11 PM »
I think what he means is that the top schock mount bolt on the Indian C5 from outside to inside goes like this: acorn nut, shock, fat seat bracket, frame (corrected) acorn nut, washer, fat seat bracket, shock, frame.  We in the US get a different seat and don't get the spacing the fat seat bracket provides to effectively make the top shock mount wide enough to be held squarely and snugly by the shock mopunt bolt.  My guess is that piece is 3/32" to 1/8" thick.

So, remove top shock mount, insert a few washers, put shock back on, bolt it up.

I was out yesterday.  65 if fine,  it will wiggle if I wiggle the bars but nothing terrible.  70, is fine but wiggling the bars makes an unsettling oscilation that clears itself but makes me not want to go faster.  I'm going to take a peek at my bike later, maybe get some washers.

Bradey, any chance of a picture to clarify what they did on your bike?

Scott
« Last Edit: August 20, 2010, 09:48:19 PM by Ducati Scotty »

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #67 on: August 20, 2010, 05:48:48 PM »
Duh!  I already have the accessory rear pillion which seems to be exactly what he's describing fro the way it mounts!  BUT I can maybe remove it and do some experiments this weekend :)

Scott

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #68 on: August 20, 2010, 05:55:34 PM »
Let me clarify, yes the axle plates and shock mount area is pretty Stout.What I mean is the week design from that point back to the pivot tube.It flexes, no gusseting or support, or arch shaped design at the pivot tube. It's basically just 3 pieces of pipe, welded in the shape of Japanese arch, Know what I mean? Like a roof on a pergala or trellis. I think it's too long for that shape, it's longer on the C-5, then on the G-5, so I read. Take one out, and push it in at the axle plates, Like Suzanne simmers does with her machine, and you'll see what I mean.

OH! - Copy THAT, GHG! I know what you are saying here now. The wheel spindle itself is an integral part of that system - it adds the "in and out" stability to the legs .... sort of triangulating it with the pivot. I DO agree with you, however, that for SERIOUS thrashing, the thing should be gusseted - or as you suggest - made from a "U"-bend tube. It would be easy to gusset the thing, though ..... Maybe that will be on my list if I can get the one that I'm riding to crack a weld .... Muah-ha-ha-ha-ha!
Spare the pig iron - spoil the part!

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #69 on: August 20, 2010, 06:17:47 PM »
Champagne for him, not for us quite yet. Still trying to figure out what he means?

Dan:

We will try to find out from him what he means or as Scott has just posted a bit of experimentation may reveal the solution to this problem for your bike too.

Looking at this issue from all different angles, it seems that the chasis design per se holds fine as long as ALL the small parts that attach to it have EXACT dimensions and spaces to not disturb its geometry.  It seems to be a sensitve desgin not a forgiving or stable design and is easily imbalanced with a slight change.  

My suggestion would be to follow what the engineer did to Bradey's bike one step at a time - to see if anything helps.  Ask Scooter Bob to send you a new spacer for rear wheel and replace it and go for a spin.  If that does not work, change spacer for swing arm.  Then go for shims on rear shock.  

When the bike is stationary, some parts seem fine BUT one cannot see what happens to that part when it is running at 70 mph.  

Hang in there - lots of brains are working to help you out. 
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #70 on: August 20, 2010, 06:21:30 PM »
I just went and a 45 mile ride at varying speeds up to 75mph, on glorious new pavement and the cracked up old stuff with the washer spacers in place. While I had no problems before, it now some how seems better,  don't know if it's a change in vibration or what, but it is something I can feel. I thinks it's worth the effort.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Re: Instability on C5
« Reply #71 on: August 20, 2010, 06:46:50 PM »
Do forgive me for my non technical explanation but I'll try to explain what Bradhey means.

On all the C5's an I am assuming the export versions as well. The rear seat frame slides out of the rear shock mounting bolts. If you observe the LH side shock upper mounting bolt, upon removal of the rear seat frame there is a bit of space left between the shock mounting and nut. Its because the rear bolt is longer then the RH side bolt to accommodate the side handle. Once you remove the rear seat frame, there is a bit of gap left and the nut does not cover up the remaining gap or the mounting bracket for the shocker flexes inwards to accommodate the gap and the alignment of the shocker on the top leans to one side a wee bit.

You need three washel to be placed before the nut can be tightened and the top shock mounting remains inline to the bottom. Long way back I had got a spacer made to exact size to fill up the gap.

In my case it did not helped with the instability.

Two days ago I had the luck to replace the tube twice in 2hrs(misfortunes of punctures)
and after that my bike ran straight without a single twitch. All I remember doing was tightening up the rear axle as hard as I could with my hands.

I wonder if you guys could try tightening the rear axle shaft to the brim and see if that helps.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #72 on: August 20, 2010, 07:14:44 PM »
DOY!!!! I did not pick up on the rear accessory seat the first thousend times I read over it, either, cause I don't got one. So excess play at the top rear shock mounts huh? Maybe, will check it when I get home. I'm still a little sceptical like scooterbob about the axle spacer and the swing arm pivot tube spacer. If the axle spacer was the wrong length, the alignment would be off, which it is not on my bike. Again with the pivot tube spacer, OK on my bike, no play in that area. I think that engineer was just covering all the bases, by replacing them.  I think the shock mount thing is more plausible. will try it tonight.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #73 on: August 20, 2010, 07:18:15 PM »
You could always put on some struts and run her ridgid to see what tells you.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Re: Instability on C5
« Reply #74 on: August 20, 2010, 07:31:51 PM »
You could always put on some struts and run her ridgid to see what tells you.

I like your idea and I quite agree with what scooter bob say's that a little something off trigers those wacky moments and sometimes its perfect.

Can anyone just try tightening up the rear axle shaft as much possible  and see if that helps.

I had the instability before I got the puncture but after putting a new tube and fixing the wheel back, it was gone. I didn't touch anything else except tightening the rear axle way too much. Usually I keep 28Psi at rear which helps a lot but this time it was 32Psi and it behaved far better.

What if the the shocks are not vertically centered on the swing arm, can that create problems ?

 

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #75 on: August 20, 2010, 07:48:08 PM »
You could always put on some struts and run her ridgid to see what tells you.
Ya , know we think alike. Was thinking that same damn thing. You beat me to the key board. :D
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #76 on: August 20, 2010, 07:51:14 PM »
I've been thinking of hardtailing mine for a while now, I might do it someday ;D
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #77 on: August 20, 2010, 07:52:12 PM »
I like your idea and I quite agree with what scooter bob say's that a little something off trigers those wacky moments and sometimes its perfect.

Can anyone just try tightening up the rear axle shaft as much possible  and see if that helps.

I had the instability before I got the puncture but after putting a new tube and fixing the wheel back, it was gone. I didn't touch anything else except tightening the rear axle way too much. Usually I keep 28Psi at rear which helps a lot but this time it was 32Psi and it behaved far better.

What if the the shocks are not vertically centered on the swing arm, can that create problems ?

 
All your doing is making a week swing arm stiffer. I would be careful about over tightening, and ruining the bearings.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #78 on: August 20, 2010, 07:54:48 PM »
Swap sides with the rear shocks, that might show something too.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Re: Instability on C5
« Reply #79 on: August 20, 2010, 08:01:33 PM »
All your doing is making a week swing arm stiffer. I would be careful about over tightening, and ruining the bearings.
The wheel was rotating freely and I hope it wasn't to tight. Gona check it in the morning.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #80 on: August 20, 2010, 08:52:47 PM »
Swap sides with the rear shocks, that might show something too.
Excellent idea !
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #81 on: August 20, 2010, 09:04:26 PM »
These shocks are gas charged I believe, one of your may have sprung a leak.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #82 on: August 20, 2010, 09:19:50 PM »
These shocks are gas charged I believe, one of your may have sprung a leak.
Yup, that too.nother good one.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #83 on: August 20, 2010, 09:38:14 PM »
I just went and a 45 mile ride at varying speeds up to 75mph, on glorious new pavement and the cracked up old stuff with the washer spacers in place. While I had no problems before, it now some how seems better,  don't know if it's a change in vibration or what, but it is something I can feel. I thinks it's worth the effort.
r80rt, where exactly did you put your washers?On the outside, under the center stand handle? Inside the top shock shroud, where the rubber shock bush is? Did you do it on both sides? I do see some side to side play, in the area of the top rubber shock bush. I think in side the shroud would be better?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #84 on: August 20, 2010, 09:46:35 PM »
I think what he means is that the top schock mount bolt on the Indian C5 from outside to inside goes like this: acorn nut, shock, fat seat bracket, frame.  

Just out for a ride.  The rear mounts for the seat are outside the shock.  So the order should be: acorn nut, washer, fat seat bracket, shock, frame.  Might be some more washers in there but no need to remove the shock it seems, just put some extra washers on the outside so the nut snugs up nicely on the shock.

Scott

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #85 on: August 20, 2010, 10:35:18 PM »
INSIDE the shock shroud text to the bushing, it you put them outside the shock mount will have to bend in to put pressure on the bushing. The top shock bolt is a shoulder bolt, washers on the outside of the shroud will do nothing. Both sides.
« Last Edit: August 20, 2010, 10:43:16 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #86 on: August 20, 2010, 10:48:40 PM »
Can you get that top shock bolt out without removing the fender?

Or perhaps one picture is worth a thousand words here.

Scott
« Last Edit: August 20, 2010, 10:51:02 PM by Ducati Scotty »

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #87 on: August 20, 2010, 10:50:39 PM »
No. I loosened the fender and raised it up. You could hack saw away part of the washer to make C's out of them and drop them over the bolt easy enough, that would probably be easier.
« Last Edit: August 20, 2010, 11:01:51 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #88 on: August 20, 2010, 11:16:28 PM »
There you go r80rt, another washer on the outside won't do sh@!, the 1/16" on both sides of the bush is were the problem is, that mechanic or engineer only crushed the bolt tabs! That slop is on top and Bottom.!  Guys how do you check the charge on these shocks, the book is vague.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #89 on: August 20, 2010, 11:31:27 PM »
If you got washers with the inside diameter a little larger than the steel collar inside the rubber bushing you could put them in to take up the slack between the bushing and the shrouds on the side.

Not sure on the shocks, I'll check my Snidal manual when I get home.

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #90 on: August 20, 2010, 11:37:28 PM »
If you got washers with the inside diameter a little larger than the steel collar inside the rubber bushing you could put them in to take up the slack between the bushing and the shrouds on the side.

Not sure on the shocks, I'll check my Snidal manual when I get home.

Scott
Yup, thats the idea scotty me boy. Check it if you would please, that would be great!
You Da Man!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #91 on: August 21, 2010, 01:27:30 AM »
 r80rt, when you loosened the rear fender on your bike, anything weird happen? Like the rear fender stay shifted on you?, you know, the ones on either side of the fender. Is your fender centered over the wheel? More importently, are your fender stays centered over the rear wheel with a loose fender? Maybe it's nothing, but there pretty sturdy and I just had a screw shoot out on me.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #92 on: August 21, 2010, 01:50:21 AM »
Didn't notice anything unusual, just had to jimmy things around a bit to get the bolts back in like any fender would be. Everything is centered like it should be.
« Last Edit: August 21, 2010, 01:53:05 AM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #93 on: August 21, 2010, 01:59:33 AM »
Alright cool. do you remember if one or both of the fender stays squeezed in on the fender? did you remove the fender Sta's? There is alot of tension on mine, so much that I can't remove the fender, without removing the stays. the one on the left on my bike, kicked over a good 1". Maybe, just maybe here's my torsional load?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #94 on: August 21, 2010, 02:02:11 AM »
No tension that I remember, it all went together and came apart easy enough.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #95 on: August 21, 2010, 02:13:00 AM »
Alright good. I'm gonna try and get a pic posted, gonna take a few. Stand by ,will ya?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #96 on: August 21, 2010, 02:14:36 AM »
I stuffed some grease rags between the tire and fender to hold things in place, then removed the fender stay bolts by the passenger pegs on both sides, then removed the stay bolts at the top by the shock towers on both sides, then I lifted the fender and stays as an assembly just high enough to pull the shock bolts out. I put it back in reverse order, no surprises or anything springing, nothing difficult about it. you may have a bent stay?
« Last Edit: August 21, 2010, 02:17:20 AM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #97 on: August 21, 2010, 02:18:24 AM »
I stuffed some grease rags between the tire and fender to hold things in place, then removed the fender stay bolts by the passenger pegs on both sides, then removed the stay bolts at the top by the shock towers on both sides, then I lifted the fender and stays as an assembly just high enough to pull the shock bolts out. I put it back in reverse order, no surprises or anything springing, nothing difficult about it. you may have a bent stay?
Maybe more then that, stand by.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #98 on: August 21, 2010, 02:39:25 AM »
Ok, anything look wrong to you in these pics?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #99 on: August 21, 2010, 02:43:08 AM »
Sure looks off center to me, now I wish I'd taken the fender off the stays so I could say for sure, I think Bob needs to look at those pictures.
« Last Edit: August 21, 2010, 12:37:49 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #100 on: August 21, 2010, 02:59:50 AM »
Yes he does, but he's probably home in his Jammie's, like any sain person would be at this hour :D Listen, when I pull on that left fender stay, like when the fender is in place, all nice and centered, the whole left side of the frame and bike moves forword and to the right. Remember the engine test? Well the bike would move to the right and back, in a clock wise fashion, get it? that left rear section of the frame is pushing the bike clock wise, so when my handle bars are straight on the highway, the bike is pushing right. I'm unknowingly trying to steer left. The constant battle. Hot damn!!!!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #101 on: August 21, 2010, 03:20:38 AM »
 Yea know I'm  a dumb a&! for not thinking of this earlier, cause I've seen it before. On a bike I built no less. Only it was on the front. I made a cafe front fender for that blue bike you may have seen in the magazine. Well I made the thing real strong, with steal round bar beading around the edge. The bike would track straight, the alignment was good, but the damn bars were  cocked to the left. Drove me crazy, thinking the bars were bent, or the neck was twisted, maybe a bent top tree? You know that damn fender had enough strength to twist the legs a bit.
r80rt, you are the man for sticking in with me on this.
Dan
« Last Edit: August 21, 2010, 03:23:49 AM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #102 on: August 21, 2010, 03:43:40 AM »
Here's the bike.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Re: Instability on C5
« Reply #103 on: August 21, 2010, 05:09:36 AM »
Ok, anything look wrong to you in these pics?
Seems like its to the left, tyre on mine is a bit to the right but it was never in the center

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #104 on: August 21, 2010, 05:40:15 AM »
Those side fender stays are very stiff. So much so that if pushed in either direction,left or right, they will load the frame,and push it in that direction. You can imagine the fender centered between those misaligned stays. It's stored energy, constantly pushing my frame, from the left rear ,clockwise. So while your riding your bike, there's a push to the right, constantly. You don't feel the push, you feel the instability of you trying to keep the bars straight, while on the other side of the pivot, (steering head), the frame is pushing right. In this case I believe it is due to the fender stay mount, where it welded to the frame, not being welded in at the correct angle. Look closely at the pics. Notice the difference between the left and right welded in mounts?  The difference is slight at that point, but at the other end of the fender stay its huge. See what I mean?
t
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #105 on: August 21, 2010, 06:42:55 AM »
More important than the stays, the wheel seems off center between the shocks.  Not sure if that's ok or it's supposed to be like that but I doubt it.  Can you remove the stays entirely and ride without the fender for a bit?  Might need to rig a temporary light/plate.  Or maybe you just have the wrong set or wrong order of spacers on the rear wheel.

Took a quick look at the top of my shocks, all looks snug.  I'll do a more thorough investigation tomorrow and maybe take the seat off and see if it's still snug.

Scott

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #106 on: August 21, 2010, 07:02:46 AM »
Wow look at how much you guys have contributed to this thread, while I was asleep.
The C5 was truly designed for the city with sharp handling in mind, and the G5 like the old bullet for straight line stability. And hence, as suggested by Ducati scotty and Scooter bob, any deviation from near perfect tends to bring oscillation on it.

I would personally suggest all ailing bike owners to check the fastners, spacers on the rear suspension, including the swing arm and axle nut and the rear wheel. Check for alignment of front and rear wheel and test ride the bike with tyre pressure 20 front 30 rear. If it still wiggles try swapping the rear shockers from one side to the other. If this does not works than only check the innards of the swing arm like its bush, spacer and bolt, same with the rear wheel. I think this bike will need frequent attention to the rear suspension for riding at 80 MPH or above else she is just fine.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #107 on: August 21, 2010, 07:13:18 AM »
Anyone happen to have an exploded view of the rear wheel and swingarm with all spacers in order?  Ducati nicely puts the exploded views with part numbers of every bike on the web in PDF, that's really nice!  ScooterBob, any chance you can drop a hint to our friends in India?

Oh, and I suppose we might be able to take the lower frame rails as a reference and see if the wheel is centered and/or parallel with respect to the frame rather than just in line with the front wheel.

And one last thing, should we pick one thread to continue so we don't all keep going back and forth between the two?  I'm getting dizzy.  No wait, that's the wine.

Scott
« Last Edit: August 21, 2010, 07:17:13 AM by Ducati Scotty »

perri

  • Neophyte
  • *
  • Posts: 40
  • Karma: 0
  • Italy
Re: Instability on C5
« Reply #108 on: August 21, 2010, 07:21:00 AM »
c5 2009 italy

SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Re: Instability on C5
« Reply #109 on: August 21, 2010, 09:02:31 AM »
Those side fender stays are very stiff. So much so that if pushed in either direction,left or right, they will load the frame,and push it in that direction. You can imagine the fender centered between those misaligned stays. It's stored energy, constantly pushing my frame, from the left rear ,clockwise. So while your riding your bike, there's a push to the right, constantly. You don't feel the push, you feel the instability of you trying to keep the bars straight, while on the other side of the pivot, (steering head), the frame is pushing right. In this case I believe it is due to the fender stay mount, where it welded to the frame, not being welded in at the correct angle. Look closely at the pics. Notice the difference between the left and right welded in mounts?  The difference is slight at that point, but at the other end of the fender stay its huge. See what I mean?
t


I looked at the last picture, zoomed it and measured the distance from the edge of the tyre to three different positions of the shock mounting of the frame. It seems like the tyre is off centered to left by half a inch(on the computer screen at least). So nothing to do with the stays I guess.

Possibilities I can think off

Either the swing arm bars are not aligned
Spacer is of inconsistent length

@Scott- we could either take the lower frame rails but we could also take the shock mountings on the frame too

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #110 on: August 21, 2010, 11:43:02 AM »
I'd leave the fender and stays's off and go for a ride, it looks like the top stay mount on  the muffler side is welded farther forward than the other,I think you've about got her figured out.
« Last Edit: August 21, 2010, 12:33:43 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #112 on: August 21, 2010, 01:22:41 PM »
Gotta laugh :D You guys are missing it. Stop measuring by camera angles. I assure you, the spacer's are on correctly. look at the last pick, look were the wheel is ,in relation to the swing arm. It's straight, remember, alignment was just checked again.Gentilemen, it's a bad weld on the frame, at the fender stay mount.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #113 on: August 21, 2010, 01:25:55 PM »
I measured the top stay mounts on my frame. Center to center on the bolts from the top stay mount to the seat spring mount is 1 1/2"

Center of top shock mount bolt to center of top stay mount bolt is 4" it's the same on both sides.
What do you have?
« Last Edit: August 21, 2010, 01:29:36 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #114 on: August 21, 2010, 01:40:20 PM »
Not with bike now, will check for you guys, it's not the location of the mount. It's the angle at which it's been welded in.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #115 on: August 21, 2010, 01:45:13 PM »
Whip out your rat tail file and change the angle of the bolt hole ;D
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #116 on: August 21, 2010, 02:30:09 PM »

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #117 on: August 21, 2010, 02:33:33 PM »
Again my brother we think alike. ;) I think I'll leave it for now, Scooterbob gotta see this. For those of you who are not seeing this, and I know you are r80rt, I suggest you read back very carefully over this thread and the one on steering damper for C-5. Pay very close attention to what me and scooterbob are saying,Well more so scooterbob about the dynamics of the bike. Look and study the links he posted.Consider, like bob says, what at the rear of the frame could move, or more accurately exert a force. Follow all the observation's and clues. You will see why bob and I were sceptical about what that engineer in India found and how it pertained to my bike. Brady may very well have had a loose top shock, were the egg corn nut bottomed out before good contact with the top shock mount. Or that engineer stumbled across something and did not realize, or did not say. Remember he did change those two spacer's, were they bad? or was he just covering the bases?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #119 on: August 21, 2010, 06:29:33 PM »
 A simple test to confirm. Remember, my rear fender was centered over the rear wheel before taking it apart. The fender,although made of thin sheet metal, is strong in it's design. It is basically a long curved arch. That's why the Romans used it on aquaducts, and buildings. It's a strong shape on all sides. OK, if I go to the side of the offending fender stay, in my case on the rear left.And some one at the front right, just holding the bars straight. Got the picture? If I pull the left rear fender stay out to a position were it was when the fender was in place, What do you think happens? That's correct, the bars stay straight with a little resistance from the person in front, but the rear of the frame pivot's to the right at the steering head.
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #120 on: August 21, 2010, 07:14:06 PM »
GHG and Boys - BRAVO!!! I think you have found the "stored" energy in the frame! Funny that - after I got punted last summer in the parking lot (about 25 feet - I STILL hurt from that ...) my military was wonky. I got it home and took all the fender stay brackets and pannier racks, etc off of it - and VOILA! - Straight again! I figger Raj installs the fender and the stays at the same time on the bike for convenience .... and the convenience is the LEVERAGE to cram it on the frame if it's a little off. You DO need to take the tail section completely off and ride it to see if the main frame is straight (I'm bettin' it IS!) and then you can decide how to reassemble the rest without the tension in it ..... Outstanding! - Absolutely outstanding!! A good effort on all that! If, indeed, this is the case - I am going to make a FULL report to the engineers in India to let them know to watch out for all of this!  ;D
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #121 on: August 21, 2010, 10:06:00 PM »
Thanks bob, and to all you guys. Don't uncork the bottle just yet. Gotta rig up the bike for a highway test,and right now I'm just beat. Work this weekend, I'll get to her in the next couple of days, I'll report back here,
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #122 on: August 22, 2010, 01:17:26 AM »
Thanks bob, and to all you guys. Don't uncork the bottle just yet. Gotta rig up the bike for a highway test,and right now I'm just beat. Work this weekend, I'll get to her in the next couple of days, I'll report back here,
Dan.

I'm uncorkin' the bottle ANYWAY - I spent the day in the shed doing the top end of a Harley-Davis - and getting my cylinder for the WM20 clean enough to toss onto the machine table and bore ...... I'm beat as well .... but the GOOD kind of beat, you know? Let us know when you get that puppy out and up to speed, eh?
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #123 on: August 22, 2010, 03:43:52 AM »
I'm uncorkin' the bottle ANYWAY - I spent the day in the shed doing the top end of a Harley-Davis - and getting my cylinder for the WM20 clean enough to toss onto the machine table and bore ...... I'm beat as well .... but the GOOD kind of beat, you know? Let us know when you get that puppy out and up to speed, eh?
Alright, but save me some, I ain't drink'in till I know it's in the bag. Definitely the good kind of beat.  Oh yea, I know what you mean, just the down after the high. Us screw heads get are rocks off by figuring Sh%! like this out. You will be the first to know, or maybe the first person who just happens to be there, ;) Yahoo!!!!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #124 on: August 22, 2010, 06:25:06 AM »
Just to keep you guys posted. The instability issue is more serious and widespread than we think. So much so that RE is designing a new swing arm for the C5.

They have also altered the hinges on air filter box, to make it less prone to sucking in dust through the hinges, as on the older models. In fact there is a second upgrade in pipeline, which will be a sealed plastic box, fixed inside the box housing the air filter currently.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #125 on: August 22, 2010, 06:33:32 AM »
I can't see the button to attach photos. Please let me know so that I may upload the images of the old and intermediate designs of the air filter boxes.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #126 on: August 22, 2010, 07:21:18 AM »
Another data point for what it's worth:

Today was the first day I got to go for a really long ride.  I did mostly country highways from 50-75mph and some straight highway at the same speeds, up to 80 once.  Loose and tight turns in the country.  The bike is stable at all speeds.  Over 50 on a straight I can wiggle the bars and the bike will oscillate a few times but settles quickly.  It oscillates a little longer at higher speeds.  Once in a while over 50 on a straight I'll get the slightest hint of an oscillation in the bars, so small it's really hard to notice.  It goes away if I change my lane position.

Just being curious, I broke loose one of the bolts on the rear fender strut to see if it was spring loaded, the lower left one near the passenger peg.  It moved maybe 1/8", not enough to act like a spring and torque the frame.

I also too off the pillion, no difference in handling.

Scott

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #127 on: August 22, 2010, 12:18:12 PM »
I can't see the button to attach photos. Please let me know so that I may upload the images of the old and intermediate designs of the air filter boxes.
When you reply, click on additional options just below the message box, you can attach a picture there.
« Last Edit: August 22, 2010, 12:44:03 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #128 on: August 22, 2010, 01:56:32 PM »
Just to keep you guys posted. The instability issue is more serious and widespread than we think. So much so that RE is designing a new swing arm for the C5.

They have also altered the hinges on air filter box, to make it less prone to sucking in dust through the hinges, as on the older models. In fact there is a second upgrade in pipeline, which will be a sealed plastic box, fixed inside the box housing the air filter currently.
Thanks for that info Bradey, and I suspect it is. Tell you what, If that new swing arm looks anything Like the "GOrilla Brace", Me, Ducatiscotty, and the rest of the boy's who contributed, want a piece of that action. Gotta make you wonder, why a bunch of part time garage monkeys,and failing engineer majors could figure this stuff out, after the bad design, in a relatively short time. Hell, we did this on the side. Sometimes those engineers need to just put those slide rules down, step back, take a look , and just do what makes sense.
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #129 on: August 22, 2010, 03:30:48 PM »
Another data point for what it's worth:

Today was the first day I got to go for a really long ride.  I did mostly country highways from 50-75mph and some straight highway at the same speeds, up to 80 once.  Loose and tight turns in the country.  The bike is stable at all speeds.  Over 50 on a straight I can wiggle the bars and the bike will oscillate a few times but settles quickly.  It oscillates a little longer at higher speeds.  Once in a while over 50 on a straight I'll get the slightest hint of an oscillation in the bars, so small it's really hard to notice.  It goes away if I change my lane position.

Just being curious, I broke loose one of the bolts on the rear fender strut to see if it was spring loaded, the lower left one near the passenger peg.  It moved maybe 1/8", not enough to act like a spring and torque the frame.

I also too off the pillion, no difference in handling.

Scott
Thanks scotty, good info there maybe some more conformation. If there's any tention in those fender stays, you should see it when you loosen the fender mounting scews, on the stay, not so much by by loosening one of the bolts at the frame, remember, the other three bolts on the frame are still holding most, if any, of the tension back. Loosening the 4 fender mount screws, is the real tell all. An 1/8" ain't much at one bolt, but does show some tension,is it an inch on the other end? hopefully not. That fender should sit in there with neutral tension. But if your bike seems to be handling fine, I would not sweat it. LISTEN, THIS IS ONLY THE EXPIERIENCE THAT I'M HAVING WITH MY BIKE! I DO NOT THINK EVERYONE SHOULD START TEARING THERE REAR ENDS OFF TO HAVE A LOOK!
IF YOUR HAVING AN ISSUE,TAKE IT TO YOUR DEALER OR A MECHANIC! YOU COULD SCREW SOMETHING UP AND GET HURT!
 Scotty I'll take some more carfull measurements on the frame, especially around the shock towers, when I get back into it.Hopefully tonight. I am a Little concerned about just how much tension there was, and the possibility a distortion or tearing, steel tends to rip or bend and not crack. When my left fender stay is put in the correct position, like when the fender was in place, the whole left side of the frame bows out a bit.
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #130 on: August 22, 2010, 03:48:43 PM »
Thanks for that info Bradey, and I suspect it is. Tell you what, If that new swing arm looks anything Like the "GOrilla Brace", Me, Ducatiscotty, and the rest of the boy's who contributed, want a piece of that action. Gotta make you wonder, why a bunch of part time garage monkeys,and failing engineer majors could figure this stuff out, after the bad design, in a relatively short time. Hell, we did this on the side. Sometimes those engineers need to just put those slide rules down, step back, take a look , and just do what makes sense.
Dan.

I have to defend the engineering department at RE a little bit. These guys, for the most part, are really good engineers - what they LACK is the "get your hands dirty and MAKE it work" stuff that WE as a group just did. They also don't plan on the little Rajjes on the assembly line doing what they HAVE to do to bikes built. Remember that they are building about 4800 a month - and the demand is still around seven thousand - so the pressure is "ON" to get 'em dome .... no matter what. Yeah - the QC sorta sucks sometimes - and it's because of the brutal production schedule that things get overlooked. The UPSIDE to all this is the bikes ARE better than ever - and because they are getting built faster, the Factory is quickly learning HOW to do this and improve accuracy. All the upgrades that have come about for the C5 prove that. They are no longer just attributing the shortcomings of the bike to the fact that it's an Enfield - they are actually CHANGING things to make the bikes better! That being said - there is NO SUBSTITUTE for bruising your knuckles for 35 years and "runnin' what you brung" to teach you the REAL "in's and outs" of keeping a motorcycle under you safely. Having a burning desire to ride - and no money to do it with will make you clever - or D-E-D .... I chose clever. So far, so good!  ;)
Spare the pig iron - spoil the part!

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #131 on: August 22, 2010, 03:54:04 PM »
I agree Bob :D
« Last Edit: August 27, 2010, 02:44:25 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #132 on: August 22, 2010, 05:02:39 PM »
I have to defend the engineering department at RE a little bit. These guys, for the most part, are really good engineers - what they LACK is the "get your hands dirty and MAKE it work" stuff that WE as a group just did. They also don't plan on the little Rajjes on the assembly line doing what they HAVE to do to bikes built. Remember that they are building about 4800 a month - and the demand is still around seven thousand - so the pressure is "ON" to get 'em dome .... no matter what. Yeah - the QC sorta sucks sometimes - and it's because of the brutal production schedule that things get overlooked. The UPSIDE to all this is the bikes ARE better than ever - and because they are getting built faster, the Factory is quickly learning HOW to do this and improve accuracy. All the upgrades that have come about for the C5 prove that. They are no longer just attributing the shortcomings of the bike to the fact that it's an Enfield - they are actually CHANGING things to make the bikes better! That being said - there is NO SUBSTITUTE for bruising your knuckles for 35 years and "runnin' what you brung" to teach you the REAL "in's and outs" of keeping a motorcycle under you safely. Having a burning desire to ride - and no money to do it with will make you clever - or D-E-D .... I chose clever. So far, so good!  ;)

All true bob,all true.100% I was referring to the swing arm, not so much the fender stays.  I am all for those factory workers toiling away,more then you know. Under what conditions? I'm sure there is a huge amount of stress.
 Listen, I ain't one of those arrogant uppity types, who would say " Probably some no good lazy factory worker not do'in his job", sh%! happens. That poor slouch has been bust'in his ass all week,  While the other half of the world is sitting in a cubicle tapp'in on a keyboard.And there ain't nothing wrong with that either, but give the guy his due.
 Listen you people on this forum, better thank god you got a company like CMW,who run this VERY FRANK AND OPEN FORUM, and not a large corporation.They LET US, have these discusions to help solve a potential problem with the product they sell. Could you image if it were someone else? SH%!, I might just have a lawyer carrying a brief case, with a goon standing next to him with a set of brass knuckles in his pocket, knock'in on my door.Well there I go again gett'in all excited, that's a little extreme, but you get my point.
« Last Edit: August 22, 2010, 05:36:30 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #133 on: August 22, 2010, 06:30:37 PM »
  ???
« Last Edit: August 22, 2010, 06:33:17 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #134 on: August 22, 2010, 07:12:46 PM »
  ???
Point is simple, r80rt, Cheers to Kevin Mahoney and scooterbob for running a quality company, that is truly looking out for there customer's.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #135 on: August 22, 2010, 09:13:04 PM »
Point is simple, r80rt, Cheers to Kevin Mahoney and scooterbob for running a quality company, that is truly looking out for there customer's.

+11ty billion.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #136 on: August 22, 2010, 10:13:47 PM »
  Measurements look good!! 1 1/2"  center to center from seat spring mount to fender stay mount, both sides. Wheel is dead center between shock towers, 8" between top shock mounting bolt heads, wheel center dead on at 4". Also equal distance between the shocks both top and bottom 'bout 9 3/4" center to center, give or take a 1/16 of slop in the rubber bushing area. So far so good!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #137 on: August 22, 2010, 10:39:58 PM »
Just a tid bit, you boys ever notice how on some of these bolt heads, not all. It's a pain in the butt to get a wrench or a socket on? Like there's too much plating? Or it's some kind of weird old British size? :D I tell you what, this bike looks good with the tail section and seat removed. Prime candidate for a nice little bobber! Low profile sprung seat, short little rear fender, side mount tail light,probably get a 120 in there if you loose the chain guard,even makes the stock pipe look good, forgetaboutit!!! I know scooterbob must have something brewing ;)
« Last Edit: August 22, 2010, 11:26:48 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #138 on: August 23, 2010, 12:30:00 AM »
Just a tid bit, you boys ever notice how on some of these bolt heads, not all. It's a pain in the butt to get a wrench or a socket on? Like there's too much plating? Or it's some kind of weird old British size? :D I tell you what, this bike looks good with the tail section and seat removed. Prime candidate for a nice little bobber! Low profile sprung seat, short little rear fender, side mount tail light,probably get a 120 in there if you loose the chain guard,even makes the stock pipe look good, forgetaboutit!!! I know scooterbob must have something brewing ;)

No rear fender and stays - no chain guard - and the rear pillion seat frame propping up an old BSA bum stop ..... I mean, I thought about it .....  ;)
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #139 on: August 23, 2010, 12:42:04 AM »
No rear fender and stays - no chain guard - and the rear pillion seat frame propping up an old BSA bum stop ..... I mean, I thought about it .....  ;)
I may just put this bike back together in a different form ;) Really would not take too much ,ya know? Only little fly in the ointment is how them tool boxes look from the rear. I guess a wide low profile sprung seat would help them blend. Brown leather, lip in the back, you know like them ones you get from v-twin? Got pic of a bike I did with one on it, check it, tell me what you think.Might work nice? Hay, like that fork brace?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #140 on: August 23, 2010, 01:05:35 AM »
Second point of info:

I undid the two mounting bolt for the rear fender stays on the right hand side so it was totally free.  Again, about 1/8" movement.  No frame spring here.

I had the same thoughts: both fenders off, shorty muffler, model A tail light/side plate mount, single round bar end mirror on the right .  You could make the current seat lower just by putting thinner padding on and recovering it.

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #141 on: August 23, 2010, 02:44:58 AM »
Second point of info:

I undid the two mounting bolt for the rear fender stays on the right hand side so it was totally free.  Again, about 1/8" movement.  No frame spring here.

I had the same thoughts: both fenders off, shorty muffler, model A tail light/side plate mount, single round bar end mirror on the right .  You could make the current seat lower just by putting thinner padding on and recovering it.

Scott
Good scotty, sounds like you got no tension.You better stop with all this Bobber stuff, I'm getting all worked up :P. Maybe some upsweep  trumpets/cocktail shakers? Loose the trafficators? Just ended inspections in Jersey ;). And we were all real diligent about going, too. Damn shame. That left rear passenger peg mount is a perfect location for that plate and light combo. Again, this pipe really looks good like this, pull all you stuff off, tell me if I ain't right?
 Alright back to business,I wasted enough time tonight stairing at the bike wondering what if's. She's all rigged and ready for the run and gun.Lic. plate ty rapped to seat springs,gonna have to do without the taillight.I'm 3 min from the highway, down to the next exit or two,then back home. Should take about 20 min.Tomarrow though when it's light. So to any Jersey Troopers on the forum, Officer......... Brother....... Sir.I am doing this in the interest of science and highway safety,particularly mine. ;D
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #142 on: August 23, 2010, 04:36:38 AM »
Oh, forgot the most important part. I put in those washers on the shock mounts. I put in 8, 4 on each side, upper and lower. On the top, inside the shock shroud, on either side of the rubber bushing ,on the spacer. Same thing on the bottom, inboard and outboard so everthing lines up nice. I used 1/2" flat washers, reamed out to fit nicely on the 15 or 16 mm bushing spacers. I gotta tell ya, I was a little sceptical, but this does really firm up the rear end. Checked the shocks while they were out, no apparent leaks. And both seemed to have the same tension, while pushing them down on the work bench. Not very accurate test, I know, but I have no shock testerizer ;)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #143 on: August 23, 2010, 05:05:48 AM »
  I DO NOT THINK EVERYONE SHOULD START TEARING THERE REAR ENDS OFF TO HAVE A LOOK!

I gotta tell ya, reading back over this, I could have used a better choice of words,  huh?   Geez!  What was I thinking?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #144 on: August 23, 2010, 10:27:57 PM »
 Been raining here all day, of course >:( Can't use the highway, but was able to get up to around 50 mph on some side roads, feels a lot more stable so far.I'm Crossing   fingers for tomarrow. Forcast for rain till  thursday though.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #145 on: August 25, 2010, 09:59:17 PM »
Test ride complete!!.............................. ;D :o Full details later, got some stuff to do.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #146 on: August 25, 2010, 10:06:36 PM »
Test ride complete!!.............................. ;D :o Full details later, got some stuff to do.

This is teasing - not allowed  ;).  What is the result - hurry up man !   
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #147 on: August 25, 2010, 10:51:29 PM »
+1 on that.  Ya tease!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #148 on: August 26, 2010, 03:11:17 AM »
 Give me whats left in that damn bottle scooterbob, YAHOO!!! SUCCESS!!!!
Sorry guy's did not mean to tease, really had a bunch to do.(well Just a little  ;))
Brother sing , my apologies, had to strike when the iron was hot. Sing and myself have been trying to hook up since saturday, but the weather was not cooperating. Pretty much rain ever since, with a tooth extraction yersterday.
Had a slight break in the weather today, so I shot home after work,before rush hour traffic could build, Grabbed the slightly disgruntled wife,told her to follow me on the highway, cause I ain't got no tail light. Grabbed the bike,and hit the road.
 To her utter concern and anger, I quickly lost her ;) Like riding on rails I tell ya.
Man, what a difference, Is this what I was missing for the last year? I could only get it up to 75 mph due to congestion ::),but believe me, I had plenty of stability to spare. I would say it's probably a mirror image of scooterbobs test on the very similar to mine,equipted bike. 19" front wheel, wide handlebars. Minus the rear fender, and them suns a bitch'in fender stays >:( Man what a relief, How long we been work'in on this guy's,since May,June?

Before,I could induce an oscillation at between 30-40 mph, and it would take a few times to correct, now I can't induce one. Before at 55-70 mph if I induced one,well forget it,I better get the speed down, or it's tank slapper time. Now,when i tried it at 70mph,slight oscillation, with emidiate correction.Did get the normal wind buffeting due to the seating position and handlebars, but easily managable. The eight washers i added to the shocks, does stiffen the suspension up a bit,but at the cost of comfort. but not that much. I'll take the perfomance.
 So,what do i do know? Adjust them fender stays and put it back together the way it was? Run another test to make sure? Or turn it into a factory looking Bobber now? Hummm....... Choices? Maybe I'll put it back together for now, and do it over the winter. I do have that guy patiently waiting for his 80' cb750, that was sitting in someones back yard for 5 years. Next challenge :D Gotta love this sh&! Brother sing, i'll give you a call tomarrow. I'll get some pics together for the steering damper thread, showing the Simian stabilizer  and the GOrilla Cage ::) both of which had there advantages, but did not cure this. If these were all combined,Fogetaboutit!!!
 Thanks guy's,Dan.
« Last Edit: August 26, 2010, 04:05:08 AM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #149 on: August 26, 2010, 03:56:12 AM »
Congrats!  Now get it back together so you can enjoy the rest of the riding season.

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #150 on: August 26, 2010, 04:31:55 AM »
Congrats!  Now get it back together so you can enjoy the rest of the riding season.

Scott
Heard that !!!  Thanks for all your help man, we made some cool stuff !!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #151 on: August 26, 2010, 12:10:30 PM »
Well - THERE you go!!  ;D All your hard work paid off! I'm glad to help as well, Dan - as I said, the problem was driving ME nuts as well ....... you know - "No one should have any LESS fun on an Enfield than ME!" ..... I live by that .... really!

You have been a gREat pair of hands and eyes for me - and the REST of us, as well. Your problem was probably "one in ten thousand", too ..... We all learned a LOT - but we'll probably never see THAT again!  ;) What really tickles ME is all that "engineering stuff" NOW makes sense to me with a real world application .... After reading, reviewing and studying just WHAT could cause the system (motorcycle chassis) to have cyclic oscillating instability - and having everything point to the spring effect of stored energy and then FINDING the "spring" ..... It made me giddy! THAT'S what I live for!

In the end - I'm SO glad that it worked out well - and YOU can see how steady the C5 REALLY is ...... like a ROCK! It's a well designed piece of equipment, thanks to the engineers at REM. My hat's off to those guys! DO let me know about the "button up" - bobber or whatever ..... and post a pic or two! Again - CONGRATS on a job well done!
Spare the pig iron - spoil the part!

UncleErnie

  • Grand Gearhead
  • *****
  • Posts: 2545
  • Karma: 0
Re: Instability on C5
« Reply #152 on: August 26, 2010, 12:33:04 PM »
I don't get why adding some washers would effect spring rate and rebound.
 ?
Run what ya brung

UncleErnie

  • Grand Gearhead
  • *****
  • Posts: 2545
  • Karma: 0
Re: Instability on C5
« Reply #153 on: August 26, 2010, 12:34:36 PM »
11 pages;
Might you do a shortish summary of the problem and the solution?  (I'm a little lost...)
Run what ya brung

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #154 on: August 26, 2010, 12:38:47 PM »
Glad you got it figured out.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #155 on: August 26, 2010, 01:58:27 PM »
11 pages;
Might you do a shortish summary of the problem and the solution?  (I'm a little lost...)

Correct me if I'm wrong, GHG ........

The PROBLEM - A wobble or oscillation (weave, technically) in the bike at speeds that increased in frequency as the speed increased.

The SOLUTION - The wheels were carefully aligned, the forks were "detail" serviced and the entire chassis was gone over with a fine toothed comb ..... twice ..... looking for chassis tuning faults that would cause this. Further discussion and the fact that the best chassis tuning on the Planet didn't take the weave out of the bike lead us to believe that there was "stored energy" in the rear of the frame causing the oscillation as the frame tried to correct itself. This was verified by removing the rear section of the bike - the fender stays and fender - and noting that they were, INDEED, under a great deal of tension from the original installation. A test ride with the rear section off the bike yielded the expected result - the bike is as steady as a fence rail at speed now. Thanks to Dan (the GHG!) for the due diligence, hard work and NO DANG WHINING! through the whole process. The hard work paid off - and BOY!, did we learn a lot on THIS one ....  ;)
Spare the pig iron - spoil the part!

UncleErnie

  • Grand Gearhead
  • *****
  • Posts: 2545
  • Karma: 0
Re: Instability on C5
« Reply #156 on: August 26, 2010, 02:19:40 PM »
So basically waht was needed was to just loosen all the nuts and let things generally fall into place?  That kind of makes sense...Thanks
Run what ya brung

shappers

  • Scooter
  • **
  • Posts: 55
  • Karma: 0
Re: Instability on C5
« Reply #157 on: August 26, 2010, 05:33:37 PM »
Hi y'all,
been following this with interest and got down on my hands and knees and had a look under my C5.

  I can see the foot pegs hang off a cantelevered offshoot of the frame.  A couple of inches back from them is a cross bolt that holds the side stand.  Further back is another cross bolt that holds the exhaust and the engine and the other part of the side stand and centre stand, this bolts up solid.

The front one doesn't.  Could this be adding to the spring effect at the rear of the frame?
I think I'll cut a piece of tube to fill the gap so it will bolt up solid.

Thanks for all the good work, Shappers.

Maturin

  • Grand Gearhead
  • *****
  • Posts: 790
  • Karma: 0
  • My Precious
Re: Instability on C5
« Reply #158 on: August 26, 2010, 05:46:54 PM »
Learned much, thx to everyone who contributed to this thread, especially Gorilla & Bob!
2010 G5
A Garage without a Bullet is a empty, barren hole.

When acellerating the tears of emotion must flow off horizontally to the ears.
Walter Röhrl

Cabo Cruz

  • Papa Juan
  • Grand Gearhead
  • *****
  • Posts: 2332
  • Karma: 0
Re: Instability on C5
« Reply #159 on: August 26, 2010, 07:28:29 PM »
Br. House: "But he that shall persevere to the end, he shall be saved."  Matthew, 24-13.
Long live the Bullets and those who ride them!

Keep the shiny side up, the boots on the pegs and best REgards,

Papa Juan

REA:    Member No. 119
BIKE:   2004 Royal Enfield Sixty-5
NAME: Perla

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #160 on: August 26, 2010, 07:47:59 PM »
So basically waht was needed was to just loosen all the nuts and let things generally fall into place?  That kind of makes sense...Thanks

No - The rear (BENT!) section of the bike was removed to get it to be straight ..... NOW the rear section will need to be hand fitted so as to be installed without the stress. In other words - two people shouldn't have to put the rear section on the bike with one prying with a six-foot spud bar and the other yelling "Gidda BOLT!, Gidda BOLT!" ....
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #161 on: August 26, 2010, 10:05:20 PM »
 Thanks scooterbob, perfect summation, could not have said it better myself,saved me some key tapp'in time, so i can get back to the garage and put her back together. Look guy's this is a basically an electro/mecahnical device on wheel's and like any device, whether during manufacture of after,at some point it's gonna fail. It's what happens afterwords thats Important.I think we just proved that when two sincier party's get together( Customer and Merchant), Any issue can be resolved. I've seen both sides and can relate. A little patience and understanding by both party's is all it takes. If one or the other party break down, a defencive dealer or an unreasonable customer, forget it. I think we all know what kind of great Company we're dealing with, and the type of great people on this forum.
 Look I know there's some of you out there thinking," What was that guy nuts, going through all that work, I would have brought it back to the dealer" Well ,your right, in this case you should. But for me, it was the most convienent, and another statement about CMW ,with there willingness to help and improve there product. Most places would have said "Screw this guy, He's do'in this sh%! on his own". Again, we can see what type of people were dealing with, with the true concern and interest, displayed by scooterbob.Am I nuts? no ::).Just a love for this stuff. And how cool is it, that we can openly share all of this stuff? A few years back,we'ed all be in the dark, about any issue, both dealer and customer.I  really think,forums like this only make for a better product and happier people.
 I really did enjoy getting to the bottom of this, it's the process that makes it fun.I looked forward getting home, and taking a look at what ever you guys suggested, think'in "maybe scotty,r80rt, bob,quinn, of who ever, may be right" Hell, you all been there, and you know it. It's how we have fun. Purely selfish on our parts. ::) What fun is it to go to someone and say" here fix this for me".
Thanks again boy's, your the best, now can i go and put my freek'in bike back together now? :D
Dan.
































« Last Edit: August 26, 2010, 10:13:46 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #162 on: August 26, 2010, 10:12:11 PM »
Glad you got it figured out.
Thanks man, you and me ,right there when we found it. ;) Ya made it easy be'in there online, with the comparisons. Da man!!!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #163 on: August 26, 2010, 10:28:51 PM »
I don't get why adding some washers would effect spring rate and rebound.
 ?
UncleErnie,  the washers only more solidly locked the shocks into there mounts.I had about 1/16"- to 1/8" play, in the rubber bushing/ spacer area.Top and bottom. The bushing would slide a bit ,left or right. Hay, all the little stuff adds up. Just a little less flex at the rear end and a stiffer feel.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #164 on: August 26, 2010, 10:31:42 PM »
11 pages;
Might you do a shortish summary of the problem and the solution?  (I'm a little lost...)

11 pages on this one alone!!! There's three other threads!!! :D
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #165 on: August 26, 2010, 10:35:44 PM »
Br. House: "But he that shall persevere to the end, he shall be saved."  Matthew, 24-13.

AMEN!!!
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #166 on: August 26, 2010, 10:44:35 PM »
Hi y'all,
been following this with interest and got down on my hands and knees and had a look under my C5.

  I can see the foot pegs hang off a cantelevered offshoot of the frame.  A couple of inches back from them is a cross bolt that holds the side stand.  Further back is another cross bolt that holds the exhaust and the engine and the other part of the side stand and centre stand, this bolts up solid.

The front one doesn't.  Could this be adding to the spring effect at the rear of the frame?
I think I'll cut a piece of tube to fill the gap so it will bolt up solid.

Thanks for all the good work, Shappers.


Thank's, not sure I'm getting the picture, is it loose? Which front one? The one by the pegs?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #167 on: August 27, 2010, 12:44:22 AM »
In the end - I'm SO glad that it worked out well - and YOU can see how steady the C5 REALLY is ...... like a ROCK! It's a well designed piece of equipment, thanks to the engineers at REM. My hat's off to those guys! DO let me know about the "button up" - bobber or whatever ..... and post a pic or two! Again - CONGRATS on a job well done!
 
 Will do bob, I'll post some pics of the fix. As you said, it's pretty simple. Just carefull assembly of the the fender stays, tweaking the the mounting locations were needed. Getting that rear fender to sit between the stays without any side to side pressure. The whole assembly, when installed correctly and being so strong and stiff, may even add a stabilizing effect.Like a tail on a GOrilla ;)
 SSR and Ducatiscotty. that was a good observation about the left top shock mount, the wheel IS slightly off center to the left. This is to allow clearence on the right for the sprocket/ brake drum. The rear wheel is put in line with the front wheel with the spacers, then finished off with the snails. Nice pick up on that ;) It is also compensated for in the slightly different lenghts of the fender mounting tabs on the fender stays.
« Last Edit: August 27, 2010, 12:53:49 AM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

singhg5

  • Grand Gearhead
  • *****
  • Posts: 2265
  • Karma: 0
Re: Instability on C5
« Reply #168 on: August 27, 2010, 02:49:36 AM »
Your perseverance, acute observation and analysis has resolved this issue of  instability of your C5.  Also cheers to all who positively contributed to solve this problem.  Everyone benefited from this marathon discussion and we have one more happy RE rider.   :)
1970's Jawa /  Yezdi
2006 Honda Nighthawk
2009 Royal Enfield Black G5

siddharthmenon

  • BuddhaSource
  • Neophyte
  • *
  • Posts: 11
  • Karma: 0
  • BuddhaSource
Re: Instability on C5
« Reply #169 on: August 27, 2010, 06:27:10 AM »
I think what you're experiencing is normal. I did 65 for the first time the other day and a brief wiggle of the bars created an unnerving oscillation. :) The bike is just not designed for it, and I'm ok with that. If I need to do highway, I'll take another ride.

I confirm this, this happened to me when I least expected, I was really scared after this. I am more careful when I am banking etc.

I reported this to RE workshop and one of the guy took test drive to say everything is fine and stable. I wish he was there when it happened. ::)

But its really a concern. I would suggest you guys to consult RE expert in India. I personally consult with S S Ghisad at Mumbai. He has loads of experience and was suggested by many.
Why do you feel shy to act stupid ?

Twitter : @BuddhaSource

shappers

  • Scooter
  • **
  • Posts: 55
  • Karma: 0
Re: Instability on C5
« Reply #170 on: August 27, 2010, 09:40:32 AM »
Hi GHG
it is the front one and no its not loose. But overtightening would have the effect spreading the frame behind the rear bottom engine mount and sandwiching the sump between the foot rests, there isn't much clearance down there.

I just a thought it might be worth pointing out.

Cheers, Shappers.


shappers

  • Scooter
  • **
  • Posts: 55
  • Karma: 0
Re: Instability on C5
« Reply #171 on: August 27, 2010, 10:16:06 AM »
Hello again,
I've had another look and think its purpose might be to stop the foot rests rotating the frame members they are attached to.  This definately prompts me to pop a piece of tube in there after undoing both bolts to let the frame settle and then have a careful measure up.

I don't think has a direct bearing on the this threads findings but anything to relieve stress must be useful.

Cheers, Shappers.

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #172 on: August 27, 2010, 11:38:28 AM »
Your perseverance, acute observation and analysis has resolved this issue of  instability of your C5.  Also cheers to all who positively contributed to solve this problem.  Everyone benefited from this marathon discussion and we have one more happy RE rider.   :)

And as a BIG bonus - we now know MORE about the C5 and its chassis dynamics than we EVER want to know ... Hahahaha!  ::) It's all good, though - everyone gains from this sort of stuff.
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #173 on: August 27, 2010, 03:07:16 PM »
Hello again,
I've had another look and think its purpose might be to stop the foot rests rotating the frame members they are attached to.  This definately prompts me to pop a piece of tube in there after undoing both bolts to let the frame settle and then have a careful measure up.

I don't think has a direct bearing on the this threads findings but anything to relieve stress must be useful.

Cheers, Shappers.

O k, I got ya.The BSA trick does help with smoothing out the vibes a bit. But if your having the same symptoms as me.And I don't think every one is. Don't go on any wild goose hunt ;) Take a look at our findings here. Give the tail section a look, just to rule it out. If it's ok, good, move on to the next possible cause. Good luck.
« Last Edit: August 27, 2010, 03:26:39 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #174 on: August 27, 2010, 03:30:17 PM »
Your perseverance, acute observation and analysis has resolved this issue of  instability of your C5.  Also cheers to all who positively contributed to solve this problem.  Everyone benefited from this marathon discussion and we have one more happy RE rider.   :)

Thanks brother sing, cheers to all.
 Hay, what happened to the spell checker? I arnt soo smartt and needs dat ting :D
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #175 on: August 28, 2010, 06:02:08 AM »
Thank you all guys for sharing your valuable time, thoughts and most importantly efforts to not only take this thread further, but also zero in on the problem and resolve it. I am sure that anybody facing this issue will certainly benefit from this thread, although he may need an old wrench like GHG, SBob and the likes  ;)

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #176 on: August 28, 2010, 06:55:10 AM »
Thank you all guys for sharing your valuable time, thoughts and most importantly efforts to not only take this thread further, but also zero in on the problem and resolve it. I am sure that anybody facing this issue will certainly benefit from this thread, although he may need an old wrench like GHG, SBob and the likes  ;)
Thanks to you Bradey for meeting with that Engieer and Mechanic. At that point I had pretty much exhausted possibility's. I figured what the heck, I'll take a look at the shocks. Thats when I stumbled accross the tension being stored in the fender stays. I think if you did not have that meeting, we would all still be working on it. Funny how sometimes you figure things out. Like devine intervention, or good Kharma ;) Its a good bike,and I really don't think it's going to need constent attention to keep things stable. Once it's set up correctly. I don't see why it should? Other then routine things like alignment/chain adjustments,bearing and suspension inspections. etc.
 You got to figure that this bike is only in it's 2nd year of manufacture, things could only get better. Takes time to get the bugs out, with how there made and how they ride. My bike is an 09', I bet that there have been changes in the way the bikes are made now. As long as the manufacturer pays attention to things like this, we'll be alright.
Thanks again Bradey, you saved us all from another one of my unending threads in pursuit of stability. :D
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #177 on: August 28, 2010, 04:10:22 PM »
  Gentilmen, another  thing I've found that I think is critical to check, IF, you are having the same problem as me.Along with checking the fender stays for loading the frame, you must ensure that the notch, at the front of the fender is properly seated into the rubber bushing, on the mount, on the frame, under the seat. That rubber bushing seams to have a dampening effect on the whole tail section of the bike. I guess it, gets rid of that tuneing fork effect. It's  seems to be a good design, and something that was anticipated, but if not installed correctly, I could see where it would have a negitve impact.
Dan.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #178 on: August 28, 2010, 04:54:40 PM »
 Heres a pic of the shock washer thing. Sorry, but the top mount came out blurry. You get the idea though. No side to side sliding of the rubber bush on the spacer.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #179 on: August 30, 2010, 01:16:42 AM »
 Mission complete!!!
 The tail is fully assembled, after a little adjustment of the fender stays and a little refitting of the fender. Test ridden, beutifull!!! I'm a happy camper!! Look out G-5 owners!!   You know me, I think there's a little bit of improvement needed in anything ;) With all that truck like highway stability, we'll beat you yet. :D
 Scooterbob,an amazing man.
« Last Edit: August 30, 2010, 05:43:54 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #180 on: August 30, 2010, 01:41:45 AM »
 Some more. That important rubber bush and notch at the front of the fender. Notice how it is not seated. Also new mounting hole loctions after fender correction.
« Last Edit: August 30, 2010, 01:57:21 AM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #181 on: August 30, 2010, 01:45:38 AM »
 And some more. After  a little compounding, the fender will look fine.The fender looks a little high, but the bike is on it's center stand in the first pic. Before refitting the fender, it was shifted back about 1 1/2". I  felt it looked better that way, but form must follow function. Remember, mine is one of the early bike's, The look may explain the mistake, I might make the same one. Who would think the fender structure would have such an impact on high speed  stability? ???  As a bike builder this has tought me alot, and what to look out for. I definatly think what we all learned was huge ,in all respects.

 Here's to you Ma, keep looking out for your boys ;) And yes I remember, I'll only ever have but one ;)
 Danny.
« Last Edit: August 30, 2010, 02:45:28 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #182 on: August 30, 2010, 08:05:45 AM »
This is great going for everybody who contributed to the thread. Now its time Kevin takes up this matter with the factory in India, so that the issue is taken care of on the assembly line itself (I know they are working under stress, but turning out top quality trouble free machines will be a wonderful feeling for them).

By the way, just noticed a strange thing, the engine is vibrating more ever since the tweeks were carried out to the rear end. Earlier I could do 75 MPH with a pillion and the bike was smooth as a HONDA, but now it starts to vibrate beyond 65 MPH

Not only that the top speed has come down from 90 MPH to 83 MPH. Is there something I must look into, or should I do the old BSA trick first  ;D
« Last Edit: August 30, 2010, 08:09:12 AM by BRADEY »

shappers

  • Scooter
  • **
  • Posts: 55
  • Karma: 0
Re: Instability on C5
« Reply #183 on: August 30, 2010, 09:50:30 AM »
Hi GHG, do my eyes decieve me or does the left hand shock in dsc00727 appear not to be perpendicular. The bit bolted to the swinging arm looks closer to the centre line than the top.

I've had a look at mine and it appears to be the same.  I'll try and do some careful measurements over the next few days.

As an additional observation you may have seen my attempt at raising the gearing using a Honda rear wheel. 

While doing this I noticed the rear mudguard appered to be out of line so undid both support bars nuts and bolts and straightened it all up with a length of wood.  A bit brutal I know but it did the job. 

Anyhow yesterday was the first time out where I got up to about 75mph true speed and lo and behold NO WEAVING.  With the caveat that I was leaning forward with arms more tucked in that usual and a relaxed grip on the bars.

Thats what I call a result!  And confirms what you all have been doing!

Cheers, Shappers.


gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #184 on: August 30, 2010, 03:05:04 PM »
This is great going for everybody who contributed to the thread. Now its time Kevin takes up this matter with the factory in India, so that the issue is taken care of on the assembly line itself (I know they are working under stress, but turning out top quality trouble free machines will be a wonderful feeling for them).

By the way, just noticed a strange thing, the engine is vibrating more ever since the tweeks were carried out to the rear end. Earlier I could do 75 MPH with a pillion and the bike was smooth as a HONDA, but now it starts to vibrate beyond 65 MPH

Not only that the top speed has come down from 90 MPH to 83 MPH. Is there something I must look into, or should I do the old BSA trick first  ;D
Yes great indeed! But I'm not so sure the problem is that wide spread. Again mine was a early model. After this learning process, we know what to look for. A rear fender that looks a little too far back and in, as compared to other bikes. Any loosening of the fasteners in the tail, etc. Remember, this is a single, thats why they say to check those fasteners.
 Bradey I suspect why your feeling more vibration is due to the fact, that some of that flex was removed from your tail end. Why your seeing a reduction in speed? 83 is pretty damn good. I suspect it has something to do with air flow over that gorgious tail light/plate holder. ;)
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #185 on: August 30, 2010, 03:33:50 PM »
Hi GHG, do my eyes decieve me or does the left hand shock in dsc00727 appear not to be perpendicular. The bit bolted to the swinging arm looks closer to the centre line than the top.

I've had a look at mine and it appears to be the same.  I'll try and do some careful measurements over the next few days.

As an additional observation you may have seen my attempt at raising the gearing using a Honda rear wheel.  

While doing this I noticed the rear mudguard appered to be out of line so undid both support bars nuts and bolts and straightened it all up with a length of wood.  A bit brutal I know but it did the job.  

Anyhow yesterday was the first time out where I got up to about 75mph true speed and lo and behold NO WEAVING.  With the caveat that I was leaning forward with arms more tucked in that usual and a relaxed grip on the bars.

Thats what I call a result!  And confirms what you all have been doing!

Cheers, Shappers.


Thanks shappers. The verticle angle is off a little, but I don't think it's a big deal. It's not drastic. It's due to the fact that the angle changes on the lower shock mount on the swing arm, as you tighten up the rear axle. There is flex at the rear of the swing arm. You probably noticed it when you took off your back wheel. The rubber bushing at the shock mounts compensate for this.  That why you see the sliding of the bush over the spacer, well thought out.
 The off centered position of the fender, again I think is by design. Remember they must allow for the spacing of the sprocket/ brake drum. If the fender was centered, there would be a larger gap at the right side fender stay and fender, as looking at it from the rear. That would make the fender or tail section weeker, because of the greater span and more prone to oscillate, I think.The fender is part of that whole structure. That tail structure should be centered over the frame, not just the back wheel. I bet, if you put the fender back, your results might be a little better? Maybe? And what ever you do, DON"T PUT ANY LOAD ON THE FRAME THROUGH THE FENDER STAYS :D
Dan.
« Last Edit: August 30, 2010, 08:38:58 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #186 on: August 30, 2010, 10:33:35 PM »
  Boys, just a heads up on something unrelated while I'm seeing it. A misaligned, or improperly fitted front fender will tend to pull or twist a fork leg. When fitted correctly, you should see no scratching on the schroud or fender. Everything should be nice and centered. Adjust using the mounting locations on the fender and lower fork leg.Believe me i've made the mistake. ::) There is a difference of about an inch, between the front and the rear front fender stays.10 5/8 in front 9 5/8 in back. I'm removing my hidden fork brace, and mixed them up.
« Last Edit: August 30, 2010, 11:22:42 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #187 on: September 01, 2010, 04:56:41 AM »
Yup, I got a couple little scratches on my fork shrouds too.  Re-adjusted the fender and all is well.

My C5 (2010) has a different style mount than yours GHG.  It looks like you have little tabs on the strut that the fender mounts to.  My strut has standoffs with tapped holes on the back side, the fender bolts right to it.  Must be a later design.

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #188 on: September 01, 2010, 05:23:56 AM »
Yup, I got a couple little scratches on my fork shrouds too.  Re-adjusted the fender and all is well.

My C5 (2010) has a different style mount than yours GHG.  It looks like you have little tabs on the strut that the fender mounts to.  My strut has standoffs with tapped holes on the back side, the fender bolts right to it.  Must be a later design.

Scott
Yea scott, I was told  that the new bikes have a better designed fender mounting system, from what it sound like, it's stronger. Should help take  some of that spring and waggle out of the tail .
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #189 on: September 01, 2010, 02:53:53 PM »
This is great going for everybody who contributed to the thread. Now its time Kevin takes up this matter with the factory in India, so that the issue is taken care of on the assembly line itself (I know they are working under stress, but turning out top quality trouble free machines will be a wonderful feeling for them).

By the way, just noticed a strange thing, the engine is vibrating more ever since the tweeks were carried out to the rear end. Earlier I could do 75 MPH with a pillion and the bike was smooth as a HONDA, but now it starts to vibrate beyond 65 MPH

Not only that the top speed has come down from 90 MPH to 83 MPH. Is there something I must look into, or should I do the old BSA trick first  ;D

Vibrate?  Is it the chassis or the engine?

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #190 on: September 02, 2010, 12:34:05 AM »
Vibrate?  Is it the chassis or the engine?

Scott
I'm thinking his chassis is tighter, so he's feeling it more? I have'nt noticed a difference.Like when you have a regulator buzzing, then loosen the union on the vent and it goes away. Tuneing fork effect.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #191 on: September 02, 2010, 04:35:18 PM »
R80RT, you and I got our bikes from the 1st 2 containers.  neither one of us had a stabilityproblem, but I saw that you had made some of these changes and felt it was better.  Were the improvements enought to warrent taking the rear end apart?  Especially if there aren't any identifyable "problems"? I think you just did the washers on the shocks, right? or did you realign the rear fender as well.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #192 on: September 02, 2010, 05:20:20 PM »
I just put washers at the top of the shocks, didn't do anything else. It seems slightly better, nothing amazing and I doubt it was worth the effort. If I had to have the fender off for some reason I'd put the washers in just because, but I wouldn't make a special effort to do it.
« Last Edit: September 02, 2010, 05:46:24 PM by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #193 on: September 02, 2010, 05:35:33 PM »
I'm thinking his chassis is tighter, so he's feeling it more? I have'nt noticed a difference.Like when you have a regulator buzzing, then loosen the union on the vent and it goes away. Tuneing fork effect.

Just curious because I'm noticing something similar in the last 1500 miles or so.  I'll start another thread, this one is long enough ;)

http://www.enfieldmotorcycles.com/forum/index.php/topic,8465.0.html

Scott
« Last Edit: September 02, 2010, 07:00:26 PM by Ducati Scotty »

csbdr

  • Bulleteer
  • ***
  • Posts: 222
  • Karma: 0
Re: Instability on C5
« Reply #194 on: September 02, 2010, 08:44:00 PM »
I just put washers at the top of the shocks, didn't do anything else. It seems slightly better, nothing amazing and I doubt it was worth the effort. If I had to have the fender off for some reason I'd put the washers in just because, but I wouldn't make a special effort to do it.

Good to know.  I'll keep it in mind if I ever put different shocks on the rear or something.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #195 on: September 03, 2010, 06:01:35 AM »
Gorilla wanted some pics of the newer style fender mounts.  As you can see below, there's just a threaded boss welded to the strut and the fender bolts up flush to it.

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #196 on: September 03, 2010, 02:44:46 PM »
 Thanks scott. Definatly a improved set up, not only looks better, but seems to be stronger. Direct connection to the stays/ fender. No springy tab in the middle. UMMMM............
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #197 on: September 03, 2010, 03:08:20 PM »
I suppose you could still get misaligned but at least it looks cleaner.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #198 on: September 03, 2010, 03:28:35 PM »
I suppose you could still get misaligned but at least it looks cleaner.
I'm thinking it would be tuff to get misaligned with that set up. Unless the holes were drilled wrong or short, on the the side of the fender.As long as the front of the fender is seated in the bush. With your set up, if the fender was forced due to a short drill hole, it would be noticable in a crooked fender, Ya Know? Thats a big improvement!
« Last Edit: September 03, 2010, 03:50:51 PM by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #199 on: September 03, 2010, 04:25:20 PM »
 I gotta tell ya, Good job R.E. That should really stiffen up that hole tail section, big time.Cheers to those Engineers for seeing it and making ajustments.I'll go and have some crow for lunch ::) Scotty, when you get a chance, can you have a look on the inside of the fender, tell me if you see a U  shaped brace in the area of the mounting holes?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #200 on: September 03, 2010, 04:32:18 PM »
It would turn the fender into the spring instead of the little tabs.  With the size of the struts it would be easy to be off but I think you woulc be more likely to notice.

I didn't feel any thing when I tighened those bolts but I wasn't looking for anything either.  I'll take a look later.

Scott

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #201 on: September 03, 2010, 04:58:04 PM »
It would turn the fender into the spring instead of the little tabs.  With the size of the struts it would be easy to be off but I think you woulc be more likely to notice.

I didn't feel any thing when I tighened those bolts but I wasn't looking for anything either.  I'll take a look later.

Scott
Exactly!!!!!!!!  With the benifit of a stiffer tail ! :o Multiple issue resolved!  I bet yours is fine.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

BRADEY

  • Grease Monkey
  • ****
  • Posts: 372
  • Karma: 0
Re: Instability on C5
« Reply #202 on: September 11, 2010, 11:59:34 AM »
Thought about starting a new thread, then chucked the idea because this is not an issue which will take too much of brain storming.

I wanted to know the RPMs at various speeds in various gears, for the C5. Like what is the engine RPM when the bike is doing 65 MPH in 5th cog or 4th Cog etc.

This information will help immensely in riding the bike in its comfort zone in absence of an RPM gauge, although many would know this by seat of their pants  ;D

Thank you guys.

shappers

  • Scooter
  • **
  • Posts: 55
  • Karma: 0
Re: Instability on C5
« Reply #203 on: September 11, 2010, 02:18:43 PM »
Hi Bradey,

mph/1000 revs

1       5.29
2      8.04
3     10.64
4      13.36
5      16.19

65mph is 4000 revs in 5th
and 5000revs or near in 4th

Cheers, Shappers.

prof_stack

  • Grand Gearhead
  • *****
  • Posts: 1115
  • Karma: 0
  • Ride carefully - You are invisible.
Re: Instability on C5
« Reply #204 on: November 01, 2010, 04:18:46 AM »
Today on the freeway for a short test, the C5 was fine up to an indicated 60mph (about 55 actual) and above that started to dance a little on the fine grooved surface.  I gently pressed on and had it up to about an indicated 67mph when the bike started a wobble that was VERY SCARY.  Letting off the throttle took care of it.  I was careful to not have a death grip on the handlebars.  The wind direction was with me.

The tire pressure is a little above 18/24 so I'll get them to that next weekend and give it a go.  Any other suggestions about it?  I sure would like to be able to ride at freeway speeds for the times when I have to do it. 
A Royal Enfield owner's cup is always half full.

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #205 on: November 01, 2010, 06:31:58 AM »
Grooved pavement is just nasty all around.  Try to find some smooth road for your next ride.

Also, make sure you're rear wheel is aligned properly and that there isn't excessive play in the steering head bearings. 

Scott

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Spare the pig iron - spoil the part!

CMB

  • Neophyte
  • *
  • Posts: 33
  • Karma: 0
Re: Instability on C5
« Reply #207 on: November 01, 2010, 02:49:39 PM »
Bob - telling the Prof "I can do 80 with no hands on mine" does absolutely nothing to help him with his problem.
« Last Edit: November 01, 2010, 03:12:55 PM by CMB »

ScooterBob

  • Grand Gearhead
  • *****
  • Posts: 2564
  • Karma: 0
  • Yeah - I get it ....
Re: Instability on C5
« Reply #208 on: November 01, 2010, 03:35:41 PM »
Bob - telling the Prof "I can do 80 with no hands on mine" does absolutely nothing to help him with his problem.

But it shows definitively that whatever the problem IS - it can be solved. The Prof's bike, I'm assuming, didn't fall eight feet from the top of a stack and get put back together from workbench junk. It should not be hard to sort out. All the advice in the world in the thread ..... that's why I supplied THAT link as well .... Did you look that far? I thought it would be a good idea to post the link to that so we didn't end up with another "oil thread" ... after another, after another, after another - especially since this topic has been pretty well explored and all the possibilities noted by the great fellows here on the board. Just tryin' to save the man a little RIDING TIME! Hahaha!  ;)
Spare the pig iron - spoil the part!

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #209 on: November 01, 2010, 04:06:44 PM »
  I agree with scotty and scooterbob, it sounds like the grooved pavement in this case. I get the same problem with my other bikes on the roads that have it. On much heavier bikes to. It's that finely, straight line textured concrete on highways, that sucks. I think they do it so water drains better on hilly highway sections, to prevent icing. Like scotty said, the obvious test would be on flat black top. Also prof mentioned his tire pressure was a little above the recommended setting, how much?
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

CMB

  • Neophyte
  • *
  • Posts: 33
  • Karma: 0
Re: Instability on C5
« Reply #210 on: November 01, 2010, 05:36:22 PM »
Dan - I've come to the same conclusion. I'm on a G5 and it was wiggly at speed on the freeway. I swapped the front tire for a Dunlop K70 and it got better - now it's just twitchy. On asphalt it's dead steady at freeway speeds. My dealer wants to play with the preload to see if that makes any difference. Maybe it'll throw some weight to the front and help the bike ignore the grooves.
« Last Edit: November 01, 2010, 06:10:09 PM by CMB »

prof_stack

  • Grand Gearhead
  • *****
  • Posts: 1115
  • Karma: 0
  • Ride carefully - You are invisible.
Re: Instability on C5
« Reply #211 on: November 02, 2010, 12:08:52 AM »
... especially since this topic has been pretty well explored and all the possibilities noted by the great fellows here on the board. Just tryin' to save the man a little RIDING TIME! ...

It's riding time I want to get, and be able to hit the freeway slab when needed.  But have ALL the possibilities been discussed?  I'm not sure, but am working at it.

  I agree with scotty and scooterbob, it sounds like the grooved pavement in this case. I get the same problem with my other bikes on the roads that have it. On much heavier bikes to. It's that finely, straight line textured concrete on highways, that sucks. I think they do it so water drains better on hilly highway sections, to prevent icing. Like scotty said, the obvious test would be on flat black top. Also prof mentioned his tire pressure was a little above the recommended setting, how much?

A little twitching I expected.  A big wobble I did not.  That quickly sucks the fun out of a ride, let me tell you.  The grooves are bad for skinny tires.  Could that be one reason for the recent photos of wider tires for the C5 that we saw on this forum?

Tire pressure?  Funny that - which of my 8 gauges is accurate?  The AccuGauge showed 26psi front.  The newer pencil gauge showed 22.  I will take them to the tire shop and ask them to check the gauges.  Then I'll know more.
A Royal Enfield owner's cup is always half full.

gashousegorilla

  • Grand Gearhead
  • *****
  • Posts: 2767
  • Karma: 0
Re: Instability on C5
« Reply #212 on: November 02, 2010, 01:34:41 AM »
It's riding time I want to get, and be able to hit the freeway slab when needed.  But have ALL the possibilities been discussed?  I'm not sure, but am working at it.

A little twitching I expected.  A big wobble I did not.  That quickly sucks the fun out of a ride, let me tell you.  The grooves are bad for skinny tires.  Could that be one reason for the recent photos of wider tires for the C5 that we saw on this forum?

Tire pressure?  Funny that - which of my 8 gauges is accurate?  The AccuGauge showed 26psi front.  The newer pencil gauge showed 22.  I will take them to the tire shop and ask them to check the gauges.  Then I'll know more.
Tire pressure funny?  No. Definitely not. prof, try running your tires at 18-22 front, 24-26 rear. You should see a marked improvement. The Avon road riders on your bike have a very stiff, low profile side wall, along with a very rounded tread pattern that damn near goes from rim edge to rim edge. Designed for quick cornering, as in city riding. By lowering your pressures, to what the book says, not the plate at the front of the bike, your increasing your contact patch, and adding some flex in those side walls, giving you better high speed stability.
 Do the pressures sound too low? Yes, but not on this bike. Light bike, stiff tires.Very good tires in my opinion.They are great handlers. Would wider tires with a higher side wall aspect ratio help with the high speed stuff? Probably. But the trade off would probably be handling.We have found, the people on this forum, scooterbob,and myself,from literally working and testing every aspect of this chassis , all summer and found the pressure listed above to be the best.
 Could the problem be somewhere else on your bike? Sure. loose swing arm pivot? rims not trued? loose neck bearing? Could be any number of things. BUT it sounds like tire pressure. Give it a shot, it's simple. And we put alot of leg work into it.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.

prof_stack

  • Grand Gearhead
  • *****
  • Posts: 1115
  • Karma: 0
  • Ride carefully - You are invisible.
Re: Instability on C5
« Reply #213 on: November 02, 2010, 02:36:50 AM »
Tire pressure funny?  No. Definitely not. prof, try running your tires at 18-22 front, 24-26 rear. You should see a marked improvement. The Avon road riders on your bike have a very stiff, low profile side wall, along with a very rounded tread pattern that damn near goes from rim edge to rim edge. Designed for quick cornering, as in city riding. By lowering your pressures, to what the book says, not the plate at the front of the bike, your increasing your contact patch, and adding some flex in those side walls, giving you better high speed stability.
 Do the pressures sound too low? Yes, but not on this bike. Light bike, stiff tires.Very good tires in my opinion.They are great handlers. Would wider tires with a higher side wall aspect ratio help with the high speed stuff? Probably. But the trade off would probably be handling.We have found, the people on this forum, scooterbob,and myself,from literally working and testing every aspect of this chassis , all summer and found the pressure listed above to be the best.
 Could the problem be somewhere else on your bike? Sure. loose swing arm pivot? rims not trued? loose neck bearing? Could be any number of things. BUT it sounds like tire pressure. Give it a shot, it's simple. And we put alot of leg work into it.

Thanks!  Much appreciated.
A Royal Enfield owner's cup is always half full.

r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2985
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Re: Instability on C5
« Reply #214 on: November 02, 2010, 03:37:02 AM »
I've finally decided on 20psi front and 24 rear, It feels perfect for my 180lbs.
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association

Ice

  • Hypercafienated
  • Grand Gearhead
  • *****
  • Posts: 5084
  • Karma: 0
  • Ride In Paradise Cabo, Don and Ernie
Re: Instability on C5
« Reply #215 on: November 02, 2010, 08:10:36 AM »
Pencil gauges are the least accurate and consistent pressure measuring device.
 Dial type or digital gauges are preferable.

 Try googleing what the track day boys and racers have to say on the subject of tire pressure gauges.
I can break it better,,,,at night, in the rain, on the trail,, 20 miles from nowhere.

REA #136

"TIMEX", the '06 Iron Barrel Military that takes me everywhere I want to go... and some places I shouldn't.

prof_stack

  • Grand Gearhead
  • *****
  • Posts: 1115
  • Karma: 0
  • Ride carefully - You are invisible.
Re: Instability on C5
« Reply #216 on: November 17, 2010, 04:38:01 AM »
A quick data point on instability: 

Today I drove the car on the same grooved pavement on the interstate that I rode recently on the squirrelly C5. 

Well, darned if the car started getting a little squirrelly on that same stretch of road.  Dry pavement, too. 

So, I'll test the C5 later on another place where the road is not groovy.
A Royal Enfield owner's cup is always half full.

Eamon

  • Grand Gearhead
  • *****
  • Posts: 936
  • Karma: 0
  • Good golly Miss Molly
Re: Instability on C5
« Reply #217 on: November 17, 2010, 07:45:28 AM »
A quick data point on instability: 

Today I drove the car on the same grooved pavement on the interstate that I rode recently on the squirrelly C5. 

Well, darned if the car started getting a little squirrelly on that same stretch of road.  Dry pavement, too. 

So, I'll test the C5 later on another place where the road is not groovy.

Hi Norm,
Was this stretch on I-5?  I hit a stretch north of the U-district, but south of Northgate, where our car got quite squirrelly.  I like my grooviness to be in my music, not my pavement, thank you!

Eamon
Eamon in Seattle
2006 Bullet 500 Deluxe
http://www.sterlingloons.com

prof_stack

  • Grand Gearhead
  • *****
  • Posts: 1115
  • Karma: 0
  • Ride carefully - You are invisible.
Re: Instability on C5
« Reply #218 on: November 17, 2010, 02:28:08 PM »
Hi Norm,
Was this stretch on I-5?  I hit a stretch north of the U-district, but south of Northgate, where our car got quite squirrelly.  I like my grooviness to be in my music, not my pavement, thank you!
Eamon

BINGO!  You win the prize.  From 80th to 130th is where I've experienced the instability while zooming north on I-5.

Groovy, man!   :o
A Royal Enfield owner's cup is always half full.

bob bezin

  • Grand Gearhead
  • *****
  • Posts: 1172
  • Karma: 0
  • I ride therefore I am.
Re: Instability on C5
« Reply #219 on: November 17, 2010, 09:04:04 PM »
yep I 5..from canada to seattle my triumph was squirrling all over the road i wondered what was wrong. took the ferry to port towndsend  and went down the coast a while then to corvalis got back on I5 and it was much better (not squirrily) on the way to ashland Or. yes that northern part of I5 was the worst part of a 5,518 mile trip
2000 RE classic ,              56 matchless g80
2006 RE delux fireball       86 yamaha SRX 600
65 500cctriumph
04 bonnie black
71 750 norton.
48 whizzer

iron.head

  • Neophyte
  • *
  • Posts: 33
  • Karma: 0
Re: Instability on C5
« Reply #220 on: November 30, 2012, 09:41:03 AM »
Visited the best RE owned Workshop in my city. It was very nicely equipped with abundance of spares. The mechanics were also competent enough. One of the mechanics was working on the new TB500 and I asked him if the TB500 swing-arm would fit the C5. He said most certainly it will, but one can only come to know after giving it a try.

One of the specific features of the TB500 is the tubular swing arm which has specifically been designed to enhance stability of the bike after complaints of instability from the C5.

I plan to give the new swing-arm a try, but for that I will have to get it ordered for me and will be a waste if it doesn't fit my bike.

Jack Leis

  • Grand Gearhead
  • *****
  • Posts: 634
  • Karma: 0
  • 2011 G5 Classic, F&%king Stolen
Re: Instability on C5
« Reply #221 on: November 30, 2012, 03:04:06 PM »
What is a TB500 ? Have I missed something ?
I would much rather ride a slow bike fast than a fast bike slow    Jack

JVS

  • Grand Gearhead
  • *****
  • Posts: 973
  • Karma: 0
  • I love chicken
Re: Instability on C5
« Reply #222 on: November 30, 2012, 03:09:24 PM »
Sons continuing wars, our fathers were enemies


Jack Leis

  • Grand Gearhead
  • *****
  • Posts: 634
  • Karma: 0
  • 2011 G5 Classic, F&%king Stolen
Re: Instability on C5
« Reply #223 on: November 30, 2012, 03:22:06 PM »
Gotcha
I would much rather ride a slow bike fast than a fast bike slow    Jack

barenekd

  • Grand Gearhead
  • *****
  • Posts: 5347
  • Karma: 0
Re: Instability on C5
« Reply #224 on: November 30, 2012, 06:35:36 PM »
The I5 most any place has to be the worst road in the US.
Bare
2013 Moto Guzzi V7 Racer
2011 Black Classic G5 (RIP)
I refuse to tiptoe through life only to arrive safely at death
http://www.controllineplans.com

LarsBloodbeard

  • Grease Monkey
  • ****
  • Posts: 303
  • Karma: 0
Re: Instability on C5
« Reply #225 on: November 30, 2012, 06:43:36 PM »
Here we have the proper recovery technique for a gentle high speed oscillation. Notice the rider gets out of the saddle to add weight to the front suspension to settle the oscillation. Next, he shifts his weight to the right side of the bike to counter the weave - and then pops back into the saddle to motor off happily!

http://www.youtube.com/watch?v=6Fa0GmdSN4A&NR=1

Enjoy!

lol, nice one.

LarsBloodbeard

  • Grease Monkey
  • ****
  • Posts: 303
  • Karma: 0
Re: Instability on C5
« Reply #226 on: November 30, 2012, 06:47:19 PM »
The I5 most any place has to be the worst road in the US.
Bare

+1

It's basically a high speed railroad track for cars.

mattsz

  • Grand Gearhead
  • *****
  • Posts: 2691
  • Karma: 0
  • moto-gurdyist
Re: Instability on C5
« Reply #227 on: November 30, 2012, 07:33:14 PM »
Wow - I wonder if my first high-side will be that dramatic?!?

Jack Leis

  • Grand Gearhead
  • *****
  • Posts: 634
  • Karma: 0
  • 2011 G5 Classic, F&%king Stolen
Re: Instability on C5
« Reply #228 on: November 30, 2012, 07:55:27 PM »
Lets hope you never have one. That guy definitely has a Guardian Angel.
I would much rather ride a slow bike fast than a fast bike slow    Jack

mattsz

  • Grand Gearhead
  • *****
  • Posts: 2691
  • Karma: 0
  • moto-gurdyist
Re: Instability on C5
« Reply #229 on: December 01, 2012, 12:04:16 AM »
Thanks, Jack.  I'm not planning any.

But if I do, I hope there's a camera watching!

Craig McClure

  • Riding over 50 years
  • Grand Gearhead
  • *****
  • Posts: 813
  • Karma: 0
  • "No Future In Getting Old"
Re: Instability on C5
« Reply #230 on: December 01, 2012, 03:56:07 AM »
Just had to say that,  my 2010 G5 Deluxe, even with 19" wheels, handled like a P.O.S. when I got it.  I had to put Dunlop K70's on both wheels, better rear shocks, low rise superbike bars, & replace (sludge) fork oil, Before I felt comfortable & enjoyed riding it.
 Confident if you do the above, the ride will improve.
Best Wishes, Craig McClure

mattsz

  • Grand Gearhead
  • *****
  • Posts: 2691
  • Karma: 0
  • moto-gurdyist
Re: Instability on C5
« Reply #231 on: December 01, 2012, 12:43:03 PM »
Craig-

This brings up a point that, as a beginner to riding, I am curious about - it may be beyond the scope of this thread, but here goes...

In the context of this discussion, what exactly is bad handling?  Can it be adequately explained in a forum post, or does it have to be experienced to be understood?

As some of you know, I'm new to riding this year, and I have almost nothing to compare the handling of my bike to, other than a KLR 250 dual sport bike (ridden during my 2-day Motorcycle Safety Foundation licensing course), and a '75 BMW R60/6 (my first bike, bought last spring after the course).

The KLR was shite.  It really wasn't set up to fit me well, and was poorly maintained, i.e. it ran terribly throughout.  I literally could not brake with my right foot and shift with my left foot from the same seat position.  They couldn't get the idle speed to settle where it should have been, so it was either sitting and stalling, or sitting and racing - all weekend long they f*cked with the idle speed while I was trying to learn to ride on the damn thing.  And, we never left second gear or the parking lot, so who's to say about the ride?

The BMW (low miles, purchased long-distance, unridden by me, but at a too-good-to-pass-up good price, so I'm told) was tall and heavy, and it had carburetor and carbon build up problems that made it feel like riding a stick of stove wood around.  I fixed up the basic power problems of that bike, but sold it when, a) I found a willing buyer who had to have a mid-70's BMW and was ready to pay rather more than I did to prove it; and b) Royal Enfield had a summer sale  ;).  All but a couple of hundred miles of my riding experience has been on the B5.

"They" say the speedmaster tires are no good, but I haven't had any trouble.  Will I know that I need different tires when I fall down?  I know that there is almost no motorbike my riding style would challenge; I don't ride terribly fast (can't with our bikes, I guess, can we?), and I'm conservative in my cornering, and stopping, when I can be.  But as for ride - tires, steering, front and rear shocks - I've got nothing to go on.

Any thoughts?

motorat

  • Grease Monkey
  • ****
  • Posts: 485
  • Karma: 0
Re: Instability on C5
« Reply #232 on: December 01, 2012, 03:46:35 PM »
it is all about feeling.
i have had 17 bikes from a dr200 through a rocket3 2300cc.
when you replace the tires with another brand that has better grip you will know what everyone is talking about. the more confidence you get the better you will know what to expect from your bike.
Joe
08 dl650abs
 c5 military

Craig McClure

  • Riding over 50 years
  • Grand Gearhead
  • *****
  • Posts: 813
  • Karma: 0
  • "No Future In Getting Old"
Re: Instability on C5
« Reply #233 on: December 01, 2012, 05:17:20 PM »
Well Matt, I have spent most of my life riding, ever since I became hooked on bicycling as a youth.
   The best way I can describe handling improvements, is doing what is required, so your mount gives you the confidence (through its positive behavior comunicated to you) to go through corners faster & dodge potholes, etc without alarming you.
  If your motorcycle does not transmit positive affirmation to you that the tires are indeed gripping the road & running true, if the front end is mushy & dives while braking, & the whole bike feels to soft, floaty or remote from the road- Then changes are in order.
TIRES: Rib front tires behave badly on rain grooves. The Avon SM rear tire (first I experienced) Gave my G5 a squirmy sensation at the rear, added to the over-soft REAR SHOCKS, gave me no confidence in the bikes ability to keep me safe. Cant Loose wit Dunlop K70's 3.50 rear, 3.25 front- & they are reasonable.
FRONT FORKS:  the manual calls for 10w30 motor oil to fill. My forks felt totally unattached to the road, & a little like a Pogo stick. When I drained the legs, uneven portions of foul smelling black sludge came out. I refilled them with Amsoil ATF (basically a 20w hi quality synthetic hydraulic oil) this paired with the K70 front tire, tells me exactly where my front wheel is, & lets me feel 100% in control of it.
HANDLE BARS: the stock bars were angled up at the rear to miss the tank, they also angled back toward me. I found the position reminiscent of a water diving rod, or hedge trimming shears, & not condusive to a comfortable confident riding position (maybe somebody likes them). I changed to BIKEMASTER brand SUPERBIKE BARS, a fairly straight bar with only 3.5" rise. these give a slight forward lean & balance riders weight better between the 2 wheels.
REAR SHOCKS: I could not put out enough $$ for the Hagon shocks, but found a pair of new ordinary oil damped shocks with 250lb springs, in the 12.5" length required, My ride quality improved dramatically, with a positive certainty of where my rear wheel is, & what its doing. My G5 handles as well or better than the british singles & twins I grew up riding, & they handled great!
  Of course everyone is different, & this old bicycle racer probably has distinctly different personal priorities for his mount. It would be very hard, as being a beginning rider to know what is good in motorcycle setup. I think you would notice the difference in handling if you could take a test ride on a bike that was well sorted. ask around a local friend might help. Best Regards, Craig   
Best Wishes, Craig McClure

mattsz

  • Grand Gearhead
  • *****
  • Posts: 2691
  • Karma: 0
  • moto-gurdyist
Re: Instability on C5
« Reply #234 on: December 01, 2012, 06:00:34 PM »
Thanks for that informative reply, Craig.

Thinking about it, there is something else which I, and all us newbies, would do well to consider:  When, on a bike-specific forum like this one, many experienced riders all seem to share the same opinion of factory installations, installations that my bike shares, then it's likely that making the modifications the "big guys" make will improve my bike.  And that can only be good for me, even if I don't currently ride so's I'd notice...

So, when so many of you guys I've come to admire and trust all say those OEM tires don't grip well, the rear shocks should be upgraded, and the front forks are all loaded with random amounts of slimy sludge, I take notice.  And I hope to be able, again with the help and advice of everyone here, to fix those problems, even though to me, they aren't yet problems (in other words, I haven't fallen down yet!   ;)).
« Last Edit: December 01, 2012, 09:10:07 PM by mattsz »

LarsBloodbeard

  • Grease Monkey
  • ****
  • Posts: 303
  • Karma: 0
Re: Instability on C5
« Reply #235 on: December 01, 2012, 09:01:13 PM »
Some great info there.  I'd also like to add to the discussion that basically as soon as I started riding mine I noticed the rear shocks were not dampening the springs enough.  I figured my shocks were just worn out, as is most everything on the bike.  I also noticed the tires could be much better, but I figured it was just because they were so weathered.  Plus I don't really like the type of tread the front skidmaster has.  Regarding handlebar position, I actually like the stock style.  I don't like the overly comfortable leaned-back feeling of most cruisers, nor do I like the lean-over style of sportbikes.  Maybe it's because I started riding on dirt bikes first.  I feel they're in a pretty good position, and if anything could be a tad higher.  I like to stand up periodically though, such as through dips and speedbumps.  My front forks are also horrible.  They stick and then will free up at a stop and feel like I'm stopping on a sponge.  Need to get around to servicing them...

barenekd

  • Grand Gearhead
  • *****
  • Posts: 5347
  • Karma: 0
Re: Instability on C5
« Reply #236 on: December 01, 2012, 11:00:58 PM »
When the front starts to push (understeer) to the outside of a turn, you have reached the limit of traction on the Skidmasters. A lot of people never ride that fast, but to me it occurred at a fairly low angle of bank. Unfortunately it occurred once to many times when I got into an impromptu race with some sport bikes. After all the warnings and the Skidmaster put the bike off a cliff! I put on the K70s right after that and never had any more such problems. Not mention the total improvement in steering and the general feel of the bike. Much more confidence inspiring. You can give up worrying about how squirrelly the bike feels and get on with some real riding. As for the shocks, the rear ones are too stiff with the compression damping and and kinda just bounce the rear wheel over the bumps. It's essentially the same as riding a hardtail. Different shocks are the only answer (Hagans work). The front end needs the fork oil changed immediately. It's easy enough to do, so get some fork oil and have at it.
The forks stick and again the compression damping is way too stiff. I left mine in way too long, and my body suffered accordingly. But tomorrow I'm going to give some 10wt a good workout. Results will be posted.
Bare
2013 Moto Guzzi V7 Racer
2011 Black Classic G5 (RIP)
I refuse to tiptoe through life only to arrive safely at death
http://www.controllineplans.com

Chiefharlock

  • Bulleteer
  • ***
  • Posts: 140
  • Karma: 0
Re: Instability on C5
« Reply #237 on: December 02, 2012, 07:02:15 PM »
I have a 2011 C5.  I haven never dealt with any of the high speed issues that folks have been talking about.  It's sporting the Avons that come stock with that model of bike and I have done no mods to the suspension etc.  The ONLY time things have ever been weird at all was a few months after getting the bike and I took it out on I-44 and had her up in the high 70's and I hit a stretch of the highway that had those wonderful rain grooves.  There was a slight oscillation/wobble.  Now at this point with over 5000 on the clock I get none. And that is with having her out on 44 doing 80 as well. This bike is also my FIRST motorcycle and I have found it to be nothing but nimble and easy to ride, very stable and extremely forgiving.  Throwing on a free flowing exhaust and  air filter did a lot to make the power that the bike's engine produces much more useful.  So yeah, I guess I get a bit confused when I hear folks talking about all kinds of stability issues with their C5s
Ton Up!

1 Thump

  • Grand Gearhead
  • *****
  • Posts: 1279
  • Karma: 0
Re: Instability on C5
« Reply #238 on: December 02, 2012, 07:12:18 PM »
I have a 2011 C5.  I haven never dealt with any of the high speed issues that folks have been talking about.  It's sporting the Avons that come stock with that model of bike and I have done no mods to the suspension etc.  The ONLY time things have ever been weird at all was a few months after getting the bike and I took it out on I-44 and had her up in the high 70's and I hit a stretch of the highway that had those wonderful rain grooves.  There was a slight oscillation/wobble.  Now at this point with over 5000 on the clock I get none. And that is with having her out on 44 doing 80 as well. This bike is also my FIRST motorcycle and I have found it to be nothing but nimble and easy to ride, very stable and extremely forgiving.  Throwing on a free flowing exhaust and  air filter did a lot to make the power that the bike's engine produces much more useful.  So yeah, I guess I get a bit confused when I hear folks talking about all kinds of stability issues with their C5s


Thats because yours was 'setup' right. With the geometry of the C5 a precise setup is more critical. The new C5's have a geometry that's tailored to provide a margin of error. Not that its bad, but still needs to be setup right.

If you go back and read Bradey's and GHG's posts, you will see that their issues were simple fixes (well, not for them , but you know what I mean) and should not have happened in the first place. The new C5's (premium or whatever) have a different trail (fork and tire size) that adds to stability. The thunderbird has a beefier swing arm which might also be plug and play in the C% (I hope).
« Last Edit: December 02, 2012, 07:17:55 PM by 1 Thump »

Chiefharlock

  • Bulleteer
  • ***
  • Posts: 140
  • Karma: 0
Re: Instability on C5
« Reply #239 on: December 03, 2012, 12:48:44 AM »
And you make an awesome point Thump.  The bikes weren't set up how they should have been.  A lot of the negative comments that get made, are very damning about the Bike and not about any of the set up that is involved in the assembly.  That's initial comments.  Obviously as folks post etc folks learn about less than scrupulous or experienced dealers not setting the bikes up how they should be.  It's just frustrating to see people dogging on a really great bike.
Ton Up!

barenekd

  • Grand Gearhead
  • *****
  • Posts: 5347
  • Karma: 0
Re: Instability on C5
« Reply #240 on: December 03, 2012, 02:17:48 AM »
I did get out to check out the new fork oil on a long ride today, about 260 miles down to Palomar and Julian.
The ride on the 91 and I-15 were improved to the point of feeling like I had gotten new forks, that actually moved and would glide over little bits of raised pavement instead of launching the whole bike up and slamming your teeth together. They won't quite smooth out the California Whoops, but nothing else will in this size range either. The groove weave is still about the same, but I blame that more on the road, than the forks. Handling in the twisties is still superb, and I didn't notice any alarming brake dive. The forks don't appear to be sticking anymore, either.
All-in-all, an extreme improvement in the bike without much cost or hassle. I wish I had done it right after I got the bike. I would surely highly recommend anyone who hasn't changed their fork oil to do it as soon as possible and enjoy the bike as it should be enjoyed. In comfort!
I used 200 ml of Maxima 10wt fork oil in each leg. More riding will indicate whether there is any fine tuning needed, but right now I'm happy as a frog on a lily pad!
Now, all I have to do is fine tune the bike to some new boots I just got!
Bare
 
2013 Moto Guzzi V7 Racer
2011 Black Classic G5 (RIP)
I refuse to tiptoe through life only to arrive safely at death
http://www.controllineplans.com

Ducati Scotty

  • Grand Gearhead
  • *****
  • Posts: 6224
  • Karma: 0
  • 2010 Teal C5
Re: Instability on C5
« Reply #241 on: December 03, 2012, 04:02:34 AM »
Isn't it amazing what a quart of 10w fork oil and an afternoon can do?  And by the way, I'd bet you get the same result on just about any bike, any make, any model.  I've never seen a fork thread where the spec amount came out of any fork.  They're ALL under filled and what comes out always looks like crap.

Scott

mattsz

  • Grand Gearhead
  • *****
  • Posts: 2691
  • Karma: 0
  • moto-gurdyist
Re: Instability on C5
« Reply #242 on: December 07, 2012, 12:56:16 AM »
A bit off topic here, but...  Anybody see the custom Yamaha SR250 on the Bike Exif site?

http://www.bikeexif.com/custom-yamaha-sr250

I guess those Galicians didn't read this thread before choosing their familiar-looking front tire:



Sorry - back to our regular programming...

gremlin

  • Grand Gearhead
  • *****
  • Posts: 1270
  • Karma: 0
  • "Do one thing each day that scares you"
Re: Instability on C5
« Reply #243 on: December 07, 2012, 01:44:00 AM »
I like the pseudo-steam-punk look.  very industrial.
1996 Trophy 1200
2011 RE B5
1979 XS11 w/vetter terraplane
1981 XS11 streetfighter
1983 Venture Royale
1982 CB750K
1971 Triumph Trident
1969 CB450
1966 Sears (puch) 250