You'll need a complete clutch for a pre unit Triumph twin..(Bonnie, T110 etc.) with a non shock absorber centre...Also the correct clutch sleeve adapter for M20 applications..There are two possible clutch spring types, short heavy ones and longer, lighter ones..The latter are best for use on single cylinder bikes. You'll also need the BSA clutch centre nut and washer, not the Triumph one...
Monty is a longtime friend and lives near me. Consquently he's familiar with what's needed but make sure you tell him it's for use on an M20...He supplies L.F. Harris parts which I'd recommend as the best...Ian
Make sure the clutch rollers are 1/4" x 1/4". I was sold longer ones and the clutch did not work, tried every possible remedy before it dawned on me while I was calmly looking out a train window what the real problem was.
I had the same problem as you. First the rollers in the clutch basket were the wrong size, original spring was not straight. Bought a NOS one and had the same problem...
One more question.
Is it a good idea to leave out 2 plates (a steel and a friction) on your single spring M20 clutch ?
I want to give it a try, maybe it helps in my endless struggle with false neutrals.
Yes, leaving out two plates is a good idea as it allows more room for the plates to seperate but has no adverse effect on the operation of the unit...Note that original fibre plates are .093" thick when new...Many pattern plates are too thick by quite a margin..In that case removing two plates will restore the plate 'pile' to the original height but won't provide any more clearance than the standard set up....Ian