My neighbor's 9 year old rides a little Kawasaki KLX 110. It is a great little bike, and he bought it right. When he brought it home, it smoked like a mosquito truck. He rode it for a few months knowing that we would go ahead and do a top end rebuild on it this winter.
Well, here we are. We have it torn down, and are now trying to figure out what the root cause of the oil burning is. The piston, cylinder and rings look great. No broken rings, no scoring in the cylinder etc... But the below pics are of the head. Obviously the exhaust valve is all crusted up with carbon, and the exhaust port is coked up too (see pics below).
So, we are going to go ahead and put a new head on it for $200, and call it good. This bike has very low hours, and we don't want to put more money into it than we need to.
My question is, once torn down, is there an easy way to tell what the root cause of the oil burning is? I was expecting a broken, or stuck ring, so when I didn't find that, and saw the condition of the head, I ASSUMED that the oil is getting into the combustion chamber via a bad valve seal/guide. Can this hypothesis be confirmed, or is that best done with a leakdown test prior to tear down?
Any thoughts?
Thanks,
JA
