B33 600cc?

[Gulten]

Hello from Sweden!

I have just aquired a BSA in parts, not complete. I need help with identifying it.
The frame nr is: BB31 797 and engine nr: Bb33 600cc, I cant find that combo in any lists...? I've found out that it should be a 1953 B33 solid, but that's just in 500cc, does anyone have any info on this? Mainly I need a new carb, and thinking if I should go for one to a M21 600cc?
Could it be some kind of special model for a sidecart?

Thank you //David

[MICKREEVES]

Sounds wrong to me. Are you sure it is 600, not a badly stamped 5?
I would get a B33  carb not 600.
I assume the engine is OHV??
Mick

[Gulten]

Thanks for the reply, went over to where the bike is today and took some photos. Maybe I just interpreted the stamp wrong...could 600 be the serial nr?
Sorry for newbie questions :/
I'll attach a pic of the stamp.

[Pete C]

Yes, a 1953 rigid framed 500cc B33. The 600 is the Motor number and nothing to do with the capacity.

You should have a pre-monobloc carb 289G/1AT. I bought one from Burlens a few months ago for my 1948 B33. Not cheap, but nice.
http://amalcarb.co.uk/carbspec/carburettor/spares/id/4669/

Have fun with the bike, I love mine!

Cheers
Pete

[MICKREEVES]

Lets see a picture of it.
Mick

[Gulten]

Thank tou very much for all information, now I know what to buy, and what to look for when searching the other parts It's my first British bike, and the seller was convinced it was a 600cc haha...
It's been sitting in parts in a barn for at least 40yrs, should be a nice winter project
Tomorrow I'll be cleaning all the parts, nuts and bolts so will take some more photos.

[rimotu66]

Good luck Gulten, sounds like we have similar winter projects, I have a 53 M33 and also need a new carb, I have been advised I need a 1 1/16" though?

[Pete C]

I think the B&M33 engines used a 1 1/8 289 carb then 1 1/6 when they switched to the 376 carb.