2005-2006 Honda ATV TRX500FE/FM/TM FourTrax Foreman Factory Service Manual, Page 138Get this manual
CYLINDER HEADVALVE Inspect and reface the valve seats whenever the valve guides are replaced (page 8-13)
If the stem-to-guide clearance exceeds the service limit, determine if new guide with standard dimensions would bring the clearance within toleranceIf so, replace any guides as necessary and ream to fitIf the stem-to-guide clearance exceeds the service limit with new guide, also replace the valve
VALVE GUIDE REPLACEMENT
Chill the new valve guides in freezer for about an hourBe sure to wear heavy gloves to avoid burns when handling the heated cylinder head
Heat the cylinder head to 130140C (275290F) with hot plate or ovenDo not heat the cylinder head beyond 150C (300F)Use temperature indicator sticks, available from welding supply stores, to be sure the cylinder head is heated to the proper temperature
VALVE GUIDE DRIVER
Using torch to heat the cylinder head may cause warpageSupport the cylinder head and drive the valve guides out of the cylinder head from the combustion chamber sideTOOL: Valve guide driver, 6.0 mm 07942-6570100