Have a few questions on what caused my 02 yz125 to tear up the top rod bearing.

I was riding the bike pretty hard in a sand pit. It just died.

Took the jug off today and had 3 semi deep scrathes.

It looks EXACTLY like this

http://www.thumpertalk.com/forum/showthread.php?t=793977&highlight=rod+bearing

The head and piston has a bunch of tublar metal shavings taken out and built up in certain places. I took out the piston and the bearing inside was broke in half and missing half the needle bearings. Most fell into the crank.

The crank seems good, no up and down play but correct me if im wrong, im just going to split the case and clean out the pcs.. ???

My guess is that it leaned out in the sand pit. I had about 40 hrs on the top end.

Now, can I keep this head or buy a new one? How about the jug? I have 3 scratches in the jug about 1/8th deep.

The carb did keep leaking gas when I stopped the motor, I had to tap it with a wrench to fix the float.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now