UCE B5 fork

[mattsz]

This subject came up briefly on the "What did you do" thread.  But I'm curious enough to bring it up again...

The B5 is presumably the "old-style" bullet frame with the new engine; I thought the C5 is a new design.  So did RE change the front fork of the B5, or did they use the old-style fork on the C5, and use a modified design on the G5?

How did we end up with two different fork designs, one being so much easier to drain and fill than the other?

[gremlin]

...............How did we end up with two different fork designs, one being so much easier to drain and fill than the other?...........

From a design perspective, it looks like a breakdown in communication, possibly during a restructuring of corporate management.

example:
Hey Bob !   is that new fork specification ready ?
Ya Joe, the drawings for the basic springrate & dampening are done & on the fileserver, just a bit of cleanup & they are good to go out for fabrication !
Thanks Bob, I'll tell the New Boss !     Bob?  Bob?  (Bob just got laid-off)

Joe tells new Boss - Hey Boss !  those fork drawings are available on the LAN, but - I'm not sure where Bob went.

New Boss tells Joe - go meet him at the welfare office.

New Boss accomplishes much during his climb up the ladder !  cuts costs ! reduces design time !  gets product out the door !   receives big bonus !

forks go off to manufacturing without drain plugs, workers giggle.  Buyers don't notice omission.  Mechanics laugh & count their blessings.

[mattsz]

I work for the State of Maine, Gremlin... that all sounds oddly familiar!  (I wish I could put a    here, but I'm afraid I must substitute a    , or even a     .)

forks go off to manufacturing without drain plugs...

Seriously, though - what is the threaded hole in the bottom of each fork, which feels like it has an allen screw in it (I can't see), if not a drain plug?

The manual I have says, under DISMANTLING PROCEDURE BULLET CLASSIC EFI (C5): "Remove the allen screw from the bottom tube and drain the oil."

Of course, the manual offers only one second step: "Gently tap the fork bottom tube downwards and remove the bottom tube."  More steps to remove the seals, but no mention at all of adding oil on reassembly. 

If anyone knows the story behind the evolution of the different front fork arrangements, I'm curious to hear it...

[Ducati Scotty]

Technically none of the bikes have a drain plug.  Both types of forks can loosen the bolt on the bottom that holds the damper rod to drain them.  That doesn't help you much on the C5 though because you can't refill it.  Whereas you can remove the large screws on the top of the G5 to refill the fork through the top cap, those are not drilled on the C5.  I've had the fork apart multiple times.  I believe there is nothing to stop you from drilling and tapping a dedicated drain plug on the lower fork leg.  I also think there would be no problem drilling the top cap to allow refilling.  To date no one has tried either of these mods.

The C5 was an all new frame and it was not as tall as the previous bikes so it needed a shorter fork.  There were forks in the past that had the bosses on the sliders for holding the fender.  Why didn't they just use one of those?  Why did they change the design of the bottom of the fork leg?  Why isn't the top cap open to allow refilling the fork like on the G5?  Why did they use the new style fork on the B5 which has the old style frame?  Sorry, I don't have any of those answers.

Scott

[mattsz]

Thanks Scott!

The G5 style seems to be more maintenance-friendly... does one design give better performance than the other?

[Ducati Scotty]

Their is no functional difference between them.  I'd almost go so far as to call the differences cosmetic.  The difference that makes them hard to maintain is just the lack of two holes drilled in the top caps.

Scott