Author Topic: Clutch question  (Read 616 times)

Offline goldenoldie

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Clutch question
« on: 10.03. 2013 02:53 »
Hello everyone considering doing a bit of a modification of my clutch the a10 has the "triumph" type 4 spring clutch with cush drive of the crankshaft and I'm considering if it would be possible to fit the 4 spring clutch with built in Cush drive as used on pre unit triumphs,  to make it a super smooth unit and extend primary chain life is it possible to do or will I have heaps of mucking about and problems?
Kind regards,

Offline RichardL

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Re: Clutch question
« Reply #1 on: 10.03. 2013 06:55 »
I have no experience riding a Triumph and, also, no experience with the cush clutch. Regardless, I find it difficult to believe that the improvement over the standard cush drive, if any, would be worth the trouble. It would be interesting to hear from other members about any particular experiences with unusually short-lived primary chains. I haven't heard such reports, even from the hard riders amongst us. I don't personally do enough miles to be a good judge of chain life.

Richard L.
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Online muskrat

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Re: Clutch question
« Reply #2 on: 10.03. 2013 08:15 »
 G'day Daniel, I tend to agree with Richard L. The later 4 spring will but is it worth it. I used an old style 4 spring like yours for about 8 seasons of racing with the cush spring removed and locked up. A good Reynolds chain would last a year in a dry primary oiled by what got past the crank seal, and clutched on the start grid and double down shifts only. OK oiled in the pits now & then. So that would be like 50,000 miles of road use. I have a belt primary in it now it's on the road, with the belt as the cush. I still feel the power pulses on take off.
 The '51 plunger has the same chain (duplex I know) I put in it 30 years ago.
As for probs with it I'd check part #'s of the plates, both plain and friction. And whether the basket will mate with the cush center.
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Muskys Plunger A7

Online chaterlea25

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Re: Clutch question
« Reply #3 on: 10.03. 2013 17:17 »
Hi Daniel,
The "Triumph" type clutch centre is a direct replacement for the solid one,
I have fitted a cush one to a A10 and could not tell the difference to one without????
I'll probably do it again because last week I picked up an adaptor and cush type centre for  fiver *smile* and have another A10 to convert to 4 spring

1961 Super Rocket
1963 RGS (ongoing)

Online metalflake11

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Re: Clutch question
« Reply #4 on: 10.03. 2013 17:52 »
I've always ran a Triumph clutch centre and cush drive at the same time(34 years). I can count on one hand the times I have replaced the primary chain. Very smooth operation, in a rubbery squashing , oily lobe rubbing sort of way. No harshness or pulsing has to be good!
I've always ran multigrade in the primary for a reason I can no longer remember, but I have a nice light clutch with no drag or slip with it.
England N.W
1960 A10