I recently purchased a 2003 TTR-90 as a Christmas gift for my son. The engine smoked like a two stroke engine, I pulled the jug off and I found the piston was scored but the cylinder was still in good condition. I replaced the piston with a 11:1 wiesco piston and honed the cylinder. The engine runs good but I now have a new problem.
The kickstarter seems to slip and not turn the engine over. If I work with it and get the piston off TDC it will then crank the engine over.
Do any of you have any Ideas? Does the kickstarter work through the clutch?