C: Clutch Clutch Thrust Roller - Even Plate Lift

Marcus Bowden

VOC Hon. Overseas Representative
VOC Member
Peter my handsome,
Next time you are down I'll make up a roller thrust on the end of the clutch push rod and it will lift it more squarely or you can get them from the VOCSC or Norman who makes them up too. Also, the three-piece push rod with the first stage turned from a solid bar with a forked end to attach to the actuator with 1/4" x 1/4" roller between each.
bananaman.
 

timetraveller

Well Known and Active Forum User
VOC Member
Thanks for the mention Marcus. For anyone who has trouble getting into first gear, take off the clutch cover and pull in the clutch lever. Does the outer plate of the clutch lift squarely? If not then one of the needle roller thrust race kits will make life easier. They can be obtained from me, or if I am not around, the Spares Company normally keeps them in stock and you would get one, more or less, by return of post.
 

oexing

Well Known and Active Forum User
VOC Member
But anyway, you should first check clutch spring settings and adjust accordingly so as not to have side loads and axial wobble of plates. The axial needle roller baring will be grateful for not having to cope with uneven loads from poor settings.

Vic
 

timetraveller

Well Known and Active Forum User
VOC Member
The thing is Vic that with the Vincent twin clutch the spring pressures are not really adjustable. All the screws should be tight, If not then they can come undone and start to mill their way through the clutch cover. The only way to adjust would be to shim the springs and checking the real pressure with different shims would not be an easy task. I designed the needle roller conversions to that the push rod is quite deeply into the top hat shaped actuator of the needle roller cluster and as the push rod can hardly tilt then neither can the outer plate. You are of course quite right that a balanced set of springs would be better but how to do it is a another thing.
 

greg brillus

Well Known and Active Forum User
VOC Member
Common causes of the pressure plate not lifting evenly........Push rod bent or tip not square, more common is the adjuster and /or the plug in the center is not running true.......Put the inner end of the adjuster in the lathe or even a cordless drill and spin the lot.......you will soon see how badly the run out is........other problems can be if the springs are tight in the thimbles, this will also cause poor lifting........make sure all the C 15 Spacers are all the same length.......Any of or a combination of these will cause poor lifting.......and obviously the springs need to be the same as per wire diameter, number of coils and overall length.........All in a days work on a Vin..........
 

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
Peter my handsome,
Next time you are down I'll make up a roller thrust on the end of the clutch push rod and it will lift it more squarely or you can get them from the VOCSC or Norman who makes them up too. Also, the three-piece push rod with the first stage turned from a solid bar with a forked end to attach to the actuator with 1/4" x 1/4" roller between each.
bananaman.
Marcus, will that roller thrust work with a Burman box/clutch in a Comet?
 

greg brillus

Well Known and Active Forum User
VOC Member
Martyn, You can shim the Honda clutches with washers........You find ones with the correct OD, then bore out the center bigger so it sits over the alloy pedestals, then fit these bellow the springs........You only need a couple, find the high spot on the pressure plate, then pack the spring nearest to that point........works a treat.
 

timetraveller

Well Known and Active Forum User
VOC Member
Regarding the use of the needle roller thrust race with the original Comet Burman clutch; after having designed the one for the twins one of the local Comet riders asked if I could do one for him. I made a few but did not publicise them as it is not the same problem as on a twin. I think that I have a few of the Comet ones left if anyone is interested. It is several years ago now but from memory one of the problems with the Burman clutch is that often the steel plug in the centre of the alloy plate has got a hole worn into it. This mod spreads the load more evenly and prevents or repairs that problem.
 

stu spalding

Well Known and Active Forum User
VOC Member
I get the plate lifting square by marking the high spot and swapping the nearest spring with the one opposite, it can take 2 or 3 attempts but it usually comes out alright. It helps if you've got a screwdriver bit in a reversible drill to tackle the screws. Cheers, Stu.
 
Top