Bought this year. Ran like a champ after cleaning carb. I'm the 2nd owner.
Two weeks ago, bike stalled, no compression. Pulled apart. Found two pieces of the little cam shim laying down below the rotor (flywheel?). Didn't know what the metal was, but it definitely broke the cam chain. Popped the covers off the cam and found one shim correctly in place above each cam. Original owner (or mech) must have dropped one at some point and neglected to go after it. :-(
Pulled head and cylinder. Piston and valves look to be in excellent condition. Did NOT pull valves, just looked at all five plus piston. Didn't appear to be any damage.
Put on new cam chain, set piston TDC, put cams on correctly per the manual. Put it all back together. When kicking I get no compression...ie when kicking, the kicker doesn't come to a stop, requiring the use of the compression lever on the bar. Used to start 1st time, every time.
Ideas? Is it possible the previous owner had the YZ timing (rotated exhaust cam one tooth clockwise) and now it won't start cuz I have is set to WR stock? Maybe a bent valve that I can't see unless I pull them out?
Jim in AK
Edited by marbee40, July 28, 2012 - 12:37 AM.