Thank you both for the input, it's much appreciated.
I did actually go through the Draganfly site looking at the models that the vendor listed as applications for the hub on ebay.........he didn't mention B25 Starfire tho!
Has to be said i was probably scanning through them looking for a bearing retainer , not something as chunky as the speedo drive, my knowledge of British bikes isn't what it should be but you're never too old to learn.
Thanks again.