Author Topic: starting from scratch - what clutch?  (Read 1734 times)

Offline Rocket Racer

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starting from scratch - what clutch?
« on: 21.10. 2009 08:04 »
My collection of parts based around a '55 road rocket motor currently has no clutch. I would like to run a single row chain driven clutch and retain a crankshaft cush drive. I would be interested to know 1. what clutches are recommended and 2. supplied by whom? This will be going into a racing sidecar application but I was intending to run a wet primary.

Wotcha reckon lads and lasses? ????
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
New Zealand

Offline fido

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Re: starting from scratch - what clutch?
« Reply #1 on: 21.10. 2009 09:10 »
The Triumph type four spring clutch as used on the last of the A10s would be the one to use. The adapter to fit the BSA gearbox shaft is readily available.

Offline LJ.

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Re: starting from scratch - what clutch?
« Reply #2 on: 21.10. 2009 09:26 »
Yes I'll second the four spring clutch... Just changed it from the six spring and really did make all the difference. I would think the four spring would be good enough for racing and sidecar lugging as well although there are good modern clutches available but out of my scope.
Ride Safely Lads! LJ.
**********************
1940 BSA M20 500cc Girder/Rigid- (SOLD)
1947 BSA M21 600cc Girder/Rigid-Green
1949 BSA A7   500cc Girder/Plunger Star Twin-(SOLD)
1953 BSA B33  500cc Teles/Plunger-Maroon
1961 BSA A10  650cc Golden Flash-Blue
1961 BSA A10  650cc Golden Flash-Red

Online Brian

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Re: starting from scratch - what clutch?
« Reply #3 on: 21.10. 2009 10:44 »
I seem to recall someone on the forum put a A65 clutch into a A10 and it all fitted ok. Might be easier to find one of them (and cheaper).

Hopefully whoever it was may read this thread and chime in.

Offline tombeau

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Re: starting from scratch - what clutch?
« Reply #4 on: 21.10. 2009 11:11 »
I've got an A65 on mine.
It was a very straightforward fit.
As I recall (I did it an awful long time ago) there is a standard adaptor for the clutch to fit. You need to do something about the big spring and lobes on the crank. 
Gives you triplex primary. Looking at the photo...shouldn't I have a smooth plate on the outermost side? oops.
Doesn't seem to slip.
I think Flashblack has one on his too.
Cheers,
Iain

Offline fido

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Re: starting from scratch - what clutch?
« Reply #5 on: 21.10. 2009 11:33 »
With the A65 sort you lose the crank cush drive. Is there a cush drive incorporated in the clutch?

Offline muskrat

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Re: starting from scratch - what clutch?
« Reply #6 on: 21.10. 2009 11:41 »
G'day Fido, the 4 spring will take a beating. Mine lasted 4 years on the track and is still in great shape. Just retired it to the spares cupboard in favour of a belt setup.
Cheers
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Offline tombeau

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Re: starting from scratch - what clutch?
« Reply #7 on: 21.10. 2009 12:14 »
Fido,
Yes there is a cush drive in the clutch.
Cheers,
Iain

Online chaterlea25

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Re: starting from scratch - what clutch?
« Reply #8 on: 21.10. 2009 18:13 »
Hi Rocket
For the ultimate clutch in my opinion (IKBA)
see the Suzuki conversion on one of the threads here

http://www.a7a10.net/forum/index.php/topic,1463.100.html

I know Phil Pearson does these in the UK but they are expensive!
I am going to add a Suzuki GSXR clutch basket to an existing BSA chainwheel or buy a blank sprocket and work from there  *idea* *idea*
I got the Suzuki clutch on Ebay cheap I think at £50
Cheers
John
1961 Super Rocket
1963 RGS (ongoing)

Offline flashblack

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Re: starting from scratch - what clutch?
« Reply #9 on: 21.10. 2009 20:04 »
Hi RR

 Tombeau is right, i do have the same set up as him, all i had to do was align the chain,by making the appropriate distance piece for the end of the crank, other than that it was all straight forward.
Richie
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