Hi all,


Today, in a rush as ever, I made an avoidable error & modified a rear sprocket supplied for a Triumph with Conical hub. The sprocket was supplied "ready to use" for such hubs. Now a waste of cash... frown
If I had checked it closely against the other sprockets I have, it would have revealed the new one's inner dia. to be too damn big!
My existing sprockets are 7 7/16" dia. The new one is 7 11/16" blush
Accordingly, the 5 mounting stud hole centres are in different pitch circle diameters.

So... I had assumed (never... ) that all Triumph & quite possibly BSA Conical rear hubs were the same.
It seems that this may not be the case...

I know there were detail changes to the hubs, as some have a drive side bearing boss externally threaded for a retaining / dust cap & others are plain - no thread or cap. No doubt there are other variations!

Can anyone confirm or say if there were differences in diameter of the sprocket / mounting point-ring / stud pitch circle dia. on hub. That is, differences between these rear hubs (if any) for the various Triumphs & BSA's ?
Does anyone have a dimensioned drawing/s, or at least just know the internal dimension/s of the sprocket / mounting rings of the possibly different versions of the hub?

Or can anyone point me in the right direction for this info?


BTW I don't own a Triumph or have any literature on them!