6 Spring Clutch Bearing Race

[Clive54bsa]

I recently rebuilt my gearbox on my '54 GF and I noticed the outer bearing race ( the one pressed into the chain wheel) was badly pitted, so I've purchased a new one. Does anyone know if there is a specific distance that the race is set in the chain wheel. I set it flush with the back of the chain wheel and there seem to be a lot of play when tightened up, and the clutch center, was rubbing on the race, so I pressed it in a bit farther and discovered other problems. I've found no literature online about installing a new outer race, does anyone one out in the A7/A10 world know if there is a particular measurement ?

[Sparky]

I dug up my old 6 spring clutch chainwheel (replaced it with a Triumph 4-spring) with the original bearing race installed.  The race protrudes about 0.070" outward from the raised inner boss of the chainwheel that the bearing race presses into (by outward, I am referring to the side containing the clutch plates).  I see that it's been awhile since your post, but I hope this is of some help. 

[KiwiGF]

Also assuming you still need a response to your post!

If you get the position of the outer race in the wheel wrong it can lead to clutch drag as the clutch wheel can get pressed against the clutch wheel backing plate even when the clutch is disengaged. I'm pretty sure there was a post on this some time back - but I would think you have to get the position very wrong to cause drag.

It's quite normal for the clutch wheel to wobble about when the clutch is disengaged, the more the clutch disengages the more the wobble, but I don't think you should try to to reduce that wobble by using the position of the outer race in the wheel. but I'm willing to be proved wrong!

The clutch wheel cork inserts get compressed between the backing plate and the first steel clutch plate, and the wheel is not "supposed" to touch "metal to metal" with either plate or the clutch basket for that matter (but you might find evidence it has in the past). The wheels appear to (always) end up in a position on the corks such as there is some thickness of cork insert on both sides of the wheel, thus preventing any metal to metal contact with the plates (such contact is only a problem when the clutch is being slipped of course).

I reckon the outer race is not supposed to touch metal to metal with the basket or backing plate, so that also helps determine it's correct position in the wheel.

From memory I had 040" of the outer race protruding from the gearbox side of the clutch wheel after pressing the new race in, but I just copied the position of the race I removed. The clutch works perfectly if a bit heavy, I can usually get neutral first go when at a standstill and the clutch does not slip, but I've only done 600 miles since renewing all the plates (Surfelx brand for both plain and friction) and fitting a complete new clutch bearing. I've also got an "as new" OEM clutch basket and rear backing plate.

I suppose what I'm saying is that (especially given the variation in pattern parts) it might be best to test fit all the parts you have and set the position of the outer race such no metal to metal contact between wheel/basket/plates/race is going to happen, even after the cork inserts have worn down a bit more.

[Topdad]

Clive54 bsa, sorry but the only negative vibe I ever felt towards an A10 was on one that had a 6 spring clutch ,boy was I glad to drop it in the bin and get a 4 springer ( as per sparky ) know cost /availability are issues but at very least put a 4 springer on your "to do list " I've kept mine for over 40 yrs and still feel the same way ,very best of luck with your bike BobH.

[Clive54bsa]

Thanks Topdad, KiwiGF, and Sparky, I think your advice on the 4 spring clutch is a sound proposition. I have most of the parts for the conversion, all but the adapter, they seem to be pretty pricey, I keep an eye out for one on Ebay
Cheers 

[Motoanimal]

Clive54 bsa, sorry but the only negative vibe I ever felt towards an A10 was on one that had a 6 spring clutch ,boy was I glad to drop it in the bin and get a 4 springer

Seconded!