2005-2008 Honda ATV TRX500FA/FGA Fourtrax, Rubicon Factory Service Manual, Page 172Get this manual
CYLINDER HEADVALVECAMSHAFT Mark all parts so they can be placed back in their original locations
Remove the following: spring retainer inner and outer valve springs valve stem seal valve spring seat OUTER SPRING SPRING SEAT VALVE
COTTERS
STEM SEAL RETAINER INNER SPRING
INSPECTION