Sorry to bring up an old thread , I'm looking at doing the top end on my mc18 Stumbled across this thread trying to decide what size pistons to order. Once I got the barrels off I noticed a very vague c marking on one and none on the other. Both Pistons have b markings on top and are only single ring pistons. From what I have researched on here so far (new to nsr's, excellent site but) This isn't Quite correct? I am guessing this means I will need to measure the barrels? If I was to get the barrels re-platted can I buy any A, B or C piston and Barrels will be matched or do I need the smallest piston of the lot?

Do any of the aussie bloke on here know of workshops that could replate the barrels for me?

Thanks guys