03 KX125 top end rebuild

This 125 belongs to one of my regular customers.  Over the last year, I have installed a new clutch, trued wheels, replaced fork seals, re-packed the silencer, etc.  Recently the owner had accidentally put non-mixed fuel in the tank and ran it for a while.

The pictures show the galling of the piston and the cylinder.  This may have been caused by the non-mixed fuel.  I removed the seat, tank, exhaust,  and  radiators to access the cylinder.  I then removed the cylinder.  The crank has some minimal side-to-side play but has no vertical play, so we are going to send the cylinder off to Millennium Technologies for repair and also replace the piston, ring, and wristpin.

Update 3/8/12:  I finally added some more pics of the bike going back together.  I powder coated a few parts for some added bling.  The owner of the bike TJ Maher, went on to take a win at the WNC ag center that weekend.

Author: joedean

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