Do you have a crank in the works or are you using a Hitchcock's? That is first on the list of things that my bike needs. I need to get off my ass this winter and get it running again. Ace, how much to get my current head checked over and flow tested?
Ok Ace. What do you need for the flow test on my cylinder head? Send me off a e-mail, its in my profile. Hitchcock's has a 10% discount this weekend, gonna order a crank. Any idea which one I need? I sent them off a e-mail, they offer:200160 PERFORMANCE CRANKSHAFT, 500cc (Metric, indian models)or200160B PERFORMANCE CRANKSHAFT, 500cc, IMPERIAL, alternator typeor200160D PERFORMANCE CRANKSHAFT, 500cc, IMPERIAL, no alternator typeMy bike is a 2001 Kickstart only Export 500. I do run a total loss electrical system, but I do use a crank triggered ignition in the rotor mounting keyway.
Little update on the progress without spilling any beans. This head is really flowing well with these latest mods.Everything is doing even better than expected.I think this engine is going to make huge power.I'm really really happy with what I'm seeing so far from this project!
Ups delivered my cylinder head to Mondello's yesterday!
Looks like they have started using Carrillo rods on those cranks.Same rod as we use.It's a nice crank set-up.Real strong.
That conrod will probably be made by Alpha bearings for Hitchcocks, as they have recently started making such things. They [first?] made a rod like that a couple of years back, that being a one - off for our 'short rod' 350 race engine, which retains the standard 70 X 90 dimensions. This machine was taken to 8000 rpm on the dyno on countless occasions and even saw 10,000 rpm once on the track! So, probably not Carrillo, but vey strong nonetheless B.W.
The concept is sound but the perfection of design and materials are yet lacking eh?Like the Wankel Rotary Engine and its similar issues...
Not to hi-jack, but Wankel Rotories are in a class of their own. And if they were flawed they wouldn't still be making them today. Have seen a turbo 20B Cosmo Turbo in action?They eat V8's for breakfast. The twin turbos lay down over 700hp @ 9,000 RPMs. But they are lot like an Enfield. You have to tear them down a fairly regular basis for decarbonization and apex seals (the equivalent to piston rings).http://www.youtube.com/watch?v=gK8536vxMashttp://www.srmotorsports.com/Stage5.jpg
You'd love a turbine engine.
I't would be great to come watch the first event this engine is used for!Please keep us up to date
Man that is Vincent BS HP specs which had a top speed of 125 mph and is also about 150 - 175 pounds heavier than a Bullet. This bike when completed should be listed in the single cylinder monster category.
Ace , I think you just gave away all your industrial secrets. I can hear compittion / opposition grinding away in there work shops now.The Bullet Whisperer may have to consider installing an antique super charger just to stay ahead of the pack on race day.
Wow! How do you gear a bike that makes more than three times the stock HP ? How about the transmission ?
I hope your not serious! All Ace did was put out some figures, there isn't a freezing chance in Hell that someone could take that info posted and replicate it. Short of actually buying one and scanning it with a 3D CAD laser scanner.Scottie
Nice what are you using for ignition on it? ERC
But I do have to ask--did the exhaust bracket break, or is there just some optical trickery going on? Or is the silencer really hanging that low??
BW! Please get few Gopro cams for this bike! Would love to see some onboard video of this beast nailing other vintage 500cc+ bikes!
Hi I was looking at the combustion chamber shape and see that it is no longer round. I was curious, as to whether pockets had been cut around the valves or the other area had been filled in ?. I have seen pictures of squish zones, (and I am assuming this is one), how efficient would one this small be ?.Great commentary and insight as per usual Tom, and I wish BW lots of success.
Hi I was looking at the combustion chamber shape and see that it is no longer round. I was curious, as to whether pockets had been cut around the valves or the other area had been filled in ?. I have seen pictures of squish zones, (and I am assuming this is one), how efficient would one this small
Hey BW,Any chance you have a spare set of featherbed mounts laying around? I have a modified slimline sitting in my shop. It's just waiting to get something tossed into it.
Aha, I misunderstood - lockwire - yes, we use that in abundance, for some reason I was thinking of those wires attatched to the rider that kill the engine when a rider comes off! My mistake, sorry B.W.
Cyrusb - I don't know what you mean by 'safety wire', but whatever it is, we don't need one here. B.W.
BW - You MIGHT able to answer this, but may be irrelevant due to us living in different countries. When you lock/safety wired you bike were you required to wire every single nut and stud that bolts the engine cases together? Also, when doing this, you drill thru the nut AND stud, correct? Curious as this is officially my first race vehicle build and new to having to use safety wire. I'm thinking I'm going to need a few new drill bits to accomplish this task.Scottie
So it looks like you drill thru the "corner" of the head as opposed to directly thru the center of the head?Scottie
Keep us updated on what sort of BHP you manage to get it sounds all very interesting Scotty
Do you care to mention who is designing and fabbing the piston? Scottie J
Aha!I see what you are doing there!Looks awesome!BTW, I wanted to say that if you want easier access to the lash adjuster on the rocker arms, you can drill and tap access holes in the tops of the rocker boxes above each of the adjusters, and plug them with brass pipe plugs. This allows you to grind down a narrow 12-point spanner to get in from the rocker covers and on to the lock nut, and you can put a screwdriver down thru the access hole, and make lash adjustments without removing the rocker arms.Everything is looking great!I have contacted the webmaster of a popular motorcycle blog(The Kneeslider), to see if we can get some coverage about your bike and this project out on the web. I haven't heard back yet, but I will try to get him to contact you for some info/quotes for the article, if he decides to write about this.
Interestingly, I just got an email nibble about this Big Head high-lift headwork from a racer in Oz.Seems the word is getting out.
Not sure if it's been mentioned somewhere else, but I gather that crankcase is English vs made in India?
Forgive my ignorance Paul - but what's that big red tool in the top picture, and what is it doing to the crankcase? Thanks!
An onboard video! That's all I want
This whole package is far too extreme for street use.It's intended for engine speeds higher than 8000 rpm.However, it could be "toned down" a bit, as a more streetable package, if desired. We can scale the head work to whatever rpm range is desired, and we have already done that for Kevin in Shetland with his Big Head Super Fireball, and our raised port GP head conversions for the India-made Bullet cylinder heads.It's all a matter of scaling the modifications to the application, and since this race bike is the most demanding of racing applications, it has a very exotic set of modifications, many of which would not be needed nor wanted on a street machine. Just too radical for street.
Sorry, that wont stop us from "wanting" it.What's the expression? If ten will kill me, gimme nine?
VERY impressive. Beautiful job. Was wondering it looks like the stand it's on has no ramp. Do you just pick it off when done. ERC
Hi Ace, The space between the inlet valve and piston crown was a little tight, as per the picture, the minimum clearance was 0.8mm, with no free play in the pushrod. However, I decided I would add an extra base gasket of 0.25mm, to give things a bit more room. Other options are running a slight valve clearance and / or retarding the inlet timing by a small amount. We also need to shim the long spark plug on the original plug side by a small amount, as the gap on this was closed right down as the piston was taken over TDC. The compression makes it feel like there is a brick in there when turning the engine via a spanner on the rotor nut ! [no such resistance with the plugs out, though] B.W.
I am thoroughly enjoying this thread. Reading the back and forth conversation between Ace and BW is like listening in on two mechanical geniuses talking!
That's because that is exactly what they are.
Thanks guys, you are too kind! I am still learning stuff from this as I go along - it is very interesting work! Here, we see things looking tantalisingly close, but friends, family a barbecue and some beer have halted proceedings for today We hope to make some noise tomorrow afternoon, though B.W.
I have posted a picture of yours truly aboard a Big Head Bullet raced between 1963-1971. This bike built by myself with the help of Royal Enfield Factory was the only Bullet 500 of its type used in the sport in the UK. It is interesting reading the posts on racer types now operating but I can assure everyone that Enfield were well aware of the Bullets capabilities and potential. If anyone is interested about The Fury as shown I will try an answer any questions.
You shouldn't need to be on facebook to see the vid. I'm not and I can see it.
Thanks, guys ! It is good to have her up and running again, in this latest and hopefully, most potent form. Incidentally, Ace, I can access your site to read the messages etc, but still cannot contribute in any way, but if you want to quote any of this yourself, please feel free ! B.W.
Sorry for the long absence on this topic, but there hasn't been anything to say about it for a while. Due to technical issues, we were forced to revert to the 'ordinary' head to catch the last round of racing at Cadwell Park in September and other work commitments put this project on the back burner for a while. However ... yesterday, I removed the 'ordinary' head [which gave us 40bhp on methanol and 41.5bhp on special 'petrol' when dyno'd recently] and adjusted the barrel spacers to accommodate the Ace/B.W. head [I include my initials, as I am responsible for the squish bands alone, Ace reworked the head for his high ratio rockers, titanium valves, special seats and some more porting]. Anyway, long story short, it is running again and back on 14.5:1 C.R., as opposed to 11:1, as well as the above improvements. I started her up this morning, but it is very cold and wet at the moment, so it stayed within the confines of the workshop. It was filmed and here is a link to it on F.B., I will try and get another means of accessing the video soon. B.W.https://www.facebook.com/video.php?v=407437576099468&set=o.132597770120179&type=2&theater
Thanks B.W. must be these old eyes. In the video looks like a yellow or gold color to me. ERC
Just ran a few calculations.According to my calculator, at 6000 rpm the port velocity should be about 424 feet per second, and the mach index at the valve is about .42 mach.My prediction for max torque, based on our previous work, would expect to see a torque peak at 7000 rpm, with a .49 mach index at the valve. However, with this reported result at 6000 rpm, it would seem that the torque curve is pretty wide and fat.My prediction for max hp, based on previous work, would expect to see the hp peak at 8200 rpm, with a .57 mach index at the valve.So, based on that, I think we have not seen torque peak yet, and the real power range should come between 7000 rpm - 8200 rpm, and the shift point could be as high as 8500 if necessary. This is going to be a high rpm powerband, and it was designed to be that, so I hope it turns out that way. This is based on flow speeds, and it is possible that the wave tuning, and also that "sausage" in the exhaust header may affect things that are outside of my prediction envelope with this calculation. But I think this will be a close prediction.It's always interesting when making a head design, just to see how close it comes to what was intended. Especially so, when including all the other stuff that has to play nice with it, like the cams and compression ratio, and have it come out the way we want.It's like a contest for me to do this stuff, and see how close I can come to achieving what we want to happen in the real world on the dyno and on the track. It's not a real easy task, considering something like this hi-lift roller rocker thing that has never been done before, and is really uncharted territory. It's a challenge.
How about that nitrous bung for us road going super fireballer's?
Fantastic BW!!! I couldn't help but notice how erratic the power curves are, no real defined curve per say. Is this typical of RE motors, or is there another issue that has not been worked out yet? It definitely leads me to believe that the fuel isn't being atomized correctly, but you know way more about this stuff than me.
Hi there all, thanks for the info on the exhaust Tom, I am going to check it all out against what we have on the bike at present. From your description I am pretty close however I think that our current length is still optimised for the old power curve aiming for peak power delivery between 7000 and 7500 rpm. Also I will check out the diameters you recommend. As for bell mouths I am thinking of getting some 3D printed as an easy and relatively cheap way to get a few for comparison on the dyno back to back. I'll keep you posted.
Am I right in thinking that the whole exhaust is effectively a long curved megaphone?A.