[widebear]

Assume nothing and take nothing for granted. You absolutely have to measure both the piston and the cylinder.I have a freshly plated 200 jug that was done in conjunction with the B piston that was provided as a reference, the outcome 3.5 thou piston to wall clearance, now I'm looking for an E or F piston to correct the clearance surplus. I have also seen brand new off the shelf KTM 200 pistons out of spec and unusable.Do yourself a favour do it once but do it right! I once srcewed up a perfectly good kx cylinder partly due to undertaking the job after consuming copious amounts of good European beer. I was going to re ring a vertex piston using non vertex rings. I measured the end gap which was ok then I went ahead and miked the ring thickness ,ok no prob same a vertex, then I had a couple of more ice cold Becks. What I neglegted to do was to measure the new rings depth in the ring land, they looked ok to through my beer googles no prob, fifteen minutes later after breaking the top end in, in the back alley a mysterious loss of compression resulted. End result and a screwed cylinder. All I can say is good thing I did'nt go to the bar lookin for company!