The only set of MTC 836 pistons I've had used 4th oversize (1.00 over) CB350 rings. I've actually still got a set if you find that's what you need for your pistons. They're getting harder to come by. Measure your ring grooves and post up the results and we'll help you figure out what you need. PM me if I don't get back to you, I don't always check in the regular bikes section.