BSA….maybe B33

[Jakevs11]

Hi guys,

I'm looking to find out some information on my grandads old bike, Reg "SHY 145" as can be seen in the pic. It was registered in Bristol, I can't find any info on the DVLA.
From some Googling looks like it could be a B33 model but I'm not sure at all.
Any help greatly appreciated.

[Ian C]

Looking at the larger dome on the primary cover this looks to be a C11G (1954 model year on) which is a 250cc OHV with alternator fitted as standard from Factory. The rear mudguard looks to have been altered a little as it should have more 'side' to it than on the pic. You are correct that the HY designation on the reg is from Bristol.

[neil1964]

Looks like an L plate over the rear mudguard too

What were rules on capacity limits then?

I know that when I was a teenager 250cc was the limit (before power limits and 125 became the norm)

[JABBA99]

I agree - it's a C11G.  SHY registration is Bristol between May and June 1954.
The L plate rules were up to 250cc solo, or anything with a sidecar (or a threewheeler).
Piccy from 1954 catalogue attached.