Join Date: Sep 2013
Location: Collierville, TN
Need help with rebuilding locked up KX250
I bought a '00 KX250 last week. I bought it for a rock bottom price knowing it had motor issues. The bike itself is in amazing condition and has tons of upgrades. I've never rebuilt a 2-stroke so, looking for some advice. When I got it, the seller told me he took the cylinder off and was able to determine the pin in the "wristband bearing" had come out. He thought it needed a top end rebuild and to flush the motor to get all the bearing particles out.
I haven't touched the bike until this morning. I noticed when I got it that I couldn't even kick the motor over, which seemed more than a top end rebuild... I removed the cylinder head and looked down the cylinder and much to my surprise, the seller removed the piston. I'm guessing he did this to investigate the issues. I can see the crank and connecting rod are there. The cylinder has a few scratches but, nothing too dramatic.
I plan to pull the motor later this week but, curious if others hav ever had a "wristband bearing" failure and what kind of damage you experienced. When I bought the bike, I budgeted for a lower and upper rebuild.