2005-2008 Honda ATV TRX500FA/FGA Fourtrax, Rubicon Factory Service Manual, Page 173Get this manual
CYLINDER HEADVALVECAMSHAFT Measure each follower bore I.DSERVICE LIMIT: 22.54 mm (0.887 in) Subtract each follower O.Dfrom the corresponding bore I.Dto obtain the rocker arm-to-shaft clearanceSERVICE LIMIT: 0.07 mm (0.003 in)
VALVE SPRING Measure the valve spring free length
SERVICE LIMITS: Inner: 37.8 mm (1.49 in) Outer: 49.0 mm (1.93 in)
VALVEVALVE GUIDE Check that the valve moves smoothly in the guideCheck the valve for bending, burning or abnormal wearMeasure each valve stem O.Dand record itSERVICE LIMITS: IN: 5.45 mm (0.215 in) EX: 5.43 mm (0.214 in)