Just thought i might let you guys know that a myself, and a friend bought 2 TZs and raced them for the first time last sunday. In the A main final, we finished 1st and second respectively but as he was crossing the line, his conrod snapped in half. When i got home, i opened up for a quick look inside of mine, and everything seemed OK.
A couple of days later, i tried to put the flywheel and clutch back on the engine, and found that as soon as i tighten the clutch nut, i cant spin the flywheel!
Im suspecting that there is a problem with the front bearing.
Considering that these 2 engines are new, run on 16%, not lean, with .30mm of head clearance, and broken in with heat cycling (as we do with our Novas), this is not acceptable. Our Nova based engines work a lot harder, are very quick, and last for much longer!
Lucky these OS gimmicks are as cheap as they are. This is my first and last OS...