HI Andy
""Can anybody advise if this clutch adapter with thrust washer and chainwheel that are used on the pre-unit Triumphs will also fit the BSA Super Rocket mainshaft which look to be the same as SRM supply""?
Along with Trevs comment Triumph adaptors do not have tha scroll at the back
SRM's product is unique to them as far as I know, when it comes to BSA knowledge they are at the top of the top league, if ever there is a problem with their products they stand over them
Crap products can be got anywhere 
SRM's may cost a few quid more but you can be confident of quality and fit
Knowing this saves me an awful lot of hassle and unessary grief when repairing customer bikes
Regards
John
Thanks Trev and John for your replies.
Have spoken to SRM and they have advised that the taper is different between the Triumph and BSA versions. Pity because the UK made Harris Triumph versions would be exactly the same apart from the taper and half the price?
The SRM ones also do not have the scroll cut into the rear shoulder. They claim it to be of no use, which when you look at the design with a large gap between the shoulder and the aperture in the sliding plate the scroll is not really doing a lot as you need it to be a fairly close fitting between the two surfaces.
Instead the adapter shoulder has a smooth finish and they use a thick felt washer of about 5 mm thick, which compresses between the back face of the adapter and the face of the sliding plate, not ideal but can't be any worse that the scroll on it's own?
They are currently out of stock of the baskets but I can get a L F Harris UK made one for a Triumph pre-unit that should be the same as I believe the bearing journal is the same on either adapter with 20 1/4" rollers? Much prefer to use a UK made part than a foreign made ones which a lot of the dealers stock and Harris parts are generally good?
