C: Clutch Twin clutch . centralizing plunger.

Cyborg

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Unfortunately the C20 probably has enough runout that you could try rotating the C21 to a different spot and end up with more clearance. Personally I would replace the C21. One because it would drive me nuts knowing it’s off and two it will add some additional shake to the shoe carrier etc. and three... the way governments are printing money, it won’t be long before a C21 is worth more than the family fortune.
 

Gary Gittleson

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Unfortunately the C20 probably has enough runout that you could try rotating the C21 to a different spot
I don't see any appreciable runout in C20. If there were enough to compensate for the C21 problem, I'd guess I'd have some noticeable symptoms since that would throw C13 off center as well. When the clutch is fully assembled, C23 does not inherit the eccentricity. C21 is really quite far off, very visible when it's off the bike just sitting on the bench. I measured the runout of C21 and the center of the circle of 9 holes is about 1mm off.


I wondered if C13 was a Friday job ?.
I don't think C13 is at fault here. OK. I'm convinced that I should replace C21. I was also worried about vibration caused by the out-of-balance C21. See picture of C21 off the bike below.
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Cyborg

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I was being a little over dramatic? I wouldn’t actually expect there would be enough runout on C20 to compensate for what you have there. Maybe move it away from the drum slightly. Worth checking the C20 though. Agreed C23 wouldn’t inherit the eccentricity at least not directly. Just whatever vibration and any extra runout in the carrier assembly that’s caused by the C21 being out of balance. Maybe not all that much in the grand scheme of things, but worth correcting I think.
When you receive your new C21, have a close look at it. On the back side that sits against the C13 there is a fairly substantial burr that is uneven and jagged. It will not allow the C21 to sit flush and evenly against the C13 and will cause runout on the C21. Some of it also looks like it would break off over time. Not likely the swarf would cause a problem in the clutch housing, but don’t need any extra crap in there.

PS... not sure what they used to carve that hole, but they should probably sharpen it..... also add a note to the drawing suggesting the edge should have a tiny radius?

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Robert Watson

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I have enough used parts in my "clutch box" to pretty much build a complete clutch, including 2 C21 in reasonable shape. That's if you haven't got a new one on order yet.
 

Gary Gittleson

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I have enough used parts in my "clutch box" to pretty much build a complete clutch, including 2 C21 in reasonable shape. That's if you haven't got a new one on order yet.
The kind offer is much appreciated.

I have ordered the new C21. Items usually arrive here within one business day from Coventry Spares. By the look of Cyborg's new one, a used one might be better, eh? Well no, if all that's wrong is a rough edge on a hole that doesn't require much precision, it'll be fine in the end.

I'll inspect the new C21 carefully and de-burr it as needed. Maybe it will even stop snowing sometime this year and I'll be able to report on the results.
 

Cyborg

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Other than the burr, which is a humdinger, it seems fine.

Guess you don’t want to hear about our Crocuses popping out of the ground or the Rhododendrons blooming and goldfish frolicking in the pond? Although it’s a little chilly today.....
 

craig

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Gary, Where do you purchase the torx drive 406, 2BA csk screws?

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It looked like torx drive, but maybe it is allen drive #406 screws.
 
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Marcus Bowden

VOC Hon. Overseas Representative
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Torx may be slightly better than Allan screws but the normal slots will last longer, but using an electric screw driver / torque drill the blade will slip out but a small central hole in screws, with the blade bit ground to locate in hole will make life easier. When complete get duck tape and stick it over the screws, have done this for 50 plus years, saves the machining on the inside of the cover. Part of my emergency kit is a used roll of duck tape (1/4" thick) with the center cardboard removed to the first round of sticky then placed in a vice and flat pack it, much handier to stow in a tool box.
bananaman.
 
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