Author Topic: Mystery clutch?  (Read 159 times)

Offline 64hip

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Mystery clutch?
« on: August 23, 2018, 12:55:51 PM »
Can anyone identify this clutch? Its almost certainly from a Japanese machine, but presently fitted in a Sunbeam.
Thanks

Offline chaterlea25

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Re: Mystery clutch?
« Reply #1 on: August 23, 2018, 10:15:54 PM »
Hi,
Clever looking mod  :D
Suzuki GSX (R) 's from the Eighties early ninety's used solid clutch outer drums with that tooth profile
What diameter is the outside of the drum,
I bought a few Suzi clutches on fleabay with the intention of making a replacement clutch similar to the Pearson BSA
so could measure for comparison if you need to

John

Offline john.k

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Re: Mystery clutch?
« Reply #2 on: August 24, 2018, 10:02:54 AM »
It looks very solid for a bike part......,I suspect it may be part of a clutchpack from a powershift transmission from a tractor or forklift......the involute spline is standard on machine parts......i have saved a complete tranny s worth of bits from a Ford tractor,thinking to one day use them in bikes..........after all,the Commando uses a clutchpack from some sort of industrial transmission..........the plates will tell the story....machines usually have sintered bronze linings,and the plain plates are always slightly dished to reduce oildrag...In fact when the dishing is gone,the plates need replacement.

Offline friday

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Re: Mystery clutch?
« Reply #3 on: August 24, 2018, 10:03:07 PM »
nice clutch I say .

Im writing an article that mentions commando trans
« Last Edit: August 24, 2018, 10:18:24 PM by friday »

Offline john.k

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Re: Mystery clutch?
« Reply #4 on: August 25, 2018, 01:05:38 AM »
Jap bike clutch bits are recognizable by the very shallow depth of the plates....in general ,of course,cause there are a zillion different jap clutches........The Commando is alleged to have a Coventry forklift clutch,but that wont be right,it will have only the plates .The P/S clutches work quite different to typical bikes....as the plates are applied by a single piston using oil pressure at around 300psi,and generally have a large central spring which holds the pack disengaged .The trannys are set up generally with two clutches together ,and run one engaged ,one freewheel,and a forklift tranny will have two sets of twp packs,forward /reverse,and high/low speed........giving two forward,two reverse speeds.