1963 CSR piston rings

jim griff · Post by **jim griff** » Thu Sep 08, 2011 10:43 pm

HI all,

I own a 1963 AJS CSR and am after some piston rings. The size of the pistons fitted have a size stamped on their crowns as 72.5, which I assume is a metric size? What is this in real money? Can anyone suggest an outlet where I can buy sets or individual rings?

Thanks in advance

Jim

dave16mct · Post by **dave16mct** » Fri Sep 09, 2011 12:24 am

Depends what make of piston. They sound like the Italian ones sold by JSL. If Hepolite try Thorntons, Shrewsbury.

bjork · Post by **bjork** » Fri Sep 09, 2011 12:36 am

Yes that is a metric measurement.

Try www.coxnturner.co.uk or ring 01425 652627 or 01935 826816.

They will ask you for the bore diameter, ring width and depth and the depth of the ring grooves in the piston.

There is also Thorntons at Shrewsbury. I've used them both and found both helpful and quick for out of stock piston rings.

I think the bore size is 72mm as standard (from memory=not as reliable as a workshop manual) so a 72.5mm is the first oversize (approx 0.020" in old money)
Edited by - bjork on 08 Sep 2011 11:38:36 PMEdited by - bjork on 10 Sep 2011 6:08:48 PM

Rob Harknett · Post by **Rob Harknett** » Fri Sep 09, 2011 12:51 am

When my 63 CSR was rebuilt, new rings were fitted as a precautionary measure by John Bolton at Kettering. Don't know what the rings were but the bike nipped up on a test run and he had to put the original rings back in.