8. CYLINDER/PISTON ATV 300/250 Measure the piston pin O.D. Service Limit: 16.96 mm (0.6784 in) Measure the piston O.D. Take measurement at 10 mm from the bottom and 90° to the piston pin hole. 10 mm Service Limit: 72.6 mm (2.904 in) Measure the piston-to-piston pin clearance. Service Limit: 0.02 mm (0.0008 in) CYLINDER INSPECTION Inspect the cylinder bore for wear or damage. Measure the cylinder I.D. at three levels of top, middle and bottom at 90° to the piston pin (in both X and Y directions). Cylinder I.D.: Service Limit: 72.8 mm (2.912 in) Measure the cylinder-to-piston clearance. Service Limit: 0.1 mm (0.004 in) The true roundness is the difference between the values measured in X and Y directions. The cylindricity (difference between the values measured at the three levels) is subject to the maximum value calculated. Service Limits: True Roundness: 0.05 mm (0.002 in) Cylindricity: 0.05 mm (0.002 in) 8-6