AJS & Matchless Owners Club

Hi
Couple of questions about the inner chain case on a 1963 G12 the one that came with it has been welded and is a bit buckled so I've managed to source a good replacement.
The one in the photo is the old one and it has a breather fitted but there is no holes in new case for a breather so
Question 1, should there be a breather on the case or is it a previous owner mod
Question 2, if it's a previous owners mod is it a good idea to fit it to the new case
Thanks in advance of any replies

Hi

There is already a breather facility on an unmodified chain case - I've arrowed it below:
What you have there is a PO modification.

I'd advise trying the bike in it's designed configuration before considering re-instating the PO's modification.

Regards Mick

Thanks for that
There must be lots of different cases as your photo doesn't look like either of mine
Yours looks like it has the right size hole to fit the oil seal mod to crank shaft mine
Is a lot larger hole