1998-2001 Yamaha YFM600FHM Grizzly Factory Service Manual, Page 168Get this manual
CYLINDER AND PISTON
NOTE: Measure cylinder bore "e" in parallel to and at right angles to the cylinder matching surfaceThen, find the average of the measurementsStandard Cylinder bore "c" 94.9795.02 mm (3.7393.741 in) C= X+Y elf out of specification, rebore or replace the cylinder, and replace the piston and piston rings as set2nd step Measure piston skirt diameter "p" with micrometer() 5.0 mm (0.20 in) from the piston bottom edge Piston skirt diameter "P" Standard 94.91594.965 mm (3.7373.739 in) Wear limit 95.1 mm (3.744 in)