8. CYLINDER/PISTON MXU 300/250 Remove the piston pin clip. Piston Towel Place a clean shop towel in the crankcase to keep the piston pin clip from falling into the crankcase. Press the piston pin out of the piston and remove the piston. Clip Piston Pin INSPECTION Inspect the piston, piston pin and piston rings. Remove the piston rings. Take care not to damage or break the piston rings during removal. Clean carbon deposits from the piston ring grooves. Inspect the piston wall for wear/scratches/damage. If any defects are found, replace the piston with a new one. Install the piston rings onto the piston and measure the piston ring-to-groove clearance. Service Limits (replace if over): Top: 0.09 mm (0.0036 in) 2nd: 0.09 mm (0.0036 in) 8-5