I am getting rid of the BSA 6 spring clutch on my M21 and using a early Triumph 4 spring. I have the adapter from Kidderminster and the only part I am missing is the clutch center hub. Now the question is:
The Triumph clutch hub is part number 57-0872. 6T and T100 up to 1952
The BSA clutch hub(triumph type) is part number 42-3235. A7 and A10 1960 to 1963
Both are 5 friction plate no shock absorber. Are they the same part? They certainly look the same from pictures. I can get the BSA one for free (40 miles away) but the Triumph one I would need to order. I have pre-unit Triumph's that use this clutch but nothing sitting on the bench to compare.
So did Triumph and BSA use the same part but with different part numbers??????
I am just about to change the " Empire Star" clutch on my BSA/Indian special, so I have been looking into this lately. Although I want the rubber cush version. The parts MUST be the same but with each firms own part numbers. Ron