what did i buy? a 500 or 650?

[bsa-bill]

Don't know who the librarian is at the moment Richard but they are part time and schools are on holiday this week, might have a bearing

[KiwiGF]

So both the vmcc uk and bsaoc uk have the despatcb records?

[bsa-bill]

So both the vmcc uk and bsaoc uk have the despatcb records?

They used to be held at a dept in The British Museum IIRC then I think they went to VMCC, BSAOC could have copies or access to them not sure which

[mario medeiros]

removed the paint on my frame and it reads ea7 9146 so I think it is a 1957? But what is the model called?and it ia a 650? I hope.Thanks

[muskrat]

Yes Mario that would be a '57. If it's a 650 it could be a CA10-***** A10 iron head or CA10R-**** Road Rocket with an alloy head.
Does it have full width alloy hubs? Like these (disregard the scoop).
Cheers

[mario medeiros]

No neither of my rims look like yours,will try to get some pics.again my frame vin is ea7 9146?Thanks

[Brian]

Not the rims Mario, the hubs.

1956 and 1957 used the hubs the same as the ones in the picture Muskrat has posted, before and after those years they had different hubs.

The 1956 and 1957 are full width alloy hubs, commonly called Ariel hubs as BSA "borrowed" them from Ariel.

Just had a thought, Mario have a look underneath the motor just in front of where the sump plate bolts on, or maybe one lug further up the cases. You might find a date stamped in the cases. If there is a date it wont give you a exact date for the engine but it will give you a indication of when the cases where made.

[bikerboy]

The big problem with numbers is they may have no relevance whatsoever. Plenty of people have changed engines or used a7 cases instead of a10 and vice versa. The amount of fins on the barrels show they are a10. Again the alloy head will have a casting number on it because plenty of people have thrown a7 heads on a10s.