2005-2009 Honda TRX400EX/TRX400X Service Manual, Page 52Get this manual
MAINTENANCE
VALVE CLEARANCE
NOTE: Inspect and adjust the valve clearance and decompressor clearance while the engine is cold (be low 35CI95F) Remove the heat guard plate (page 3-7)Remove the valve adjusting hole caps
Remove the tim ing hole and crankshaft hole caps
I rhe marA '5 passed when tlY' Ing ro align WI rhe Index notchrotare ttle crank shall onlv cpl.lmer cloc wise again and align ThiS must be done 10 preven rhe one-WilY decom pressor syslem rom lunCPoning and 10 amain rhe