2005-2009 Honda TRX400EX/TRX400X Service Manual, Page 122Get this manual
CYLINDER HEADVALVE Wrap the cyl inder head ith shop towels to prevent spilling engine oil loosen the twelve 6-mm bolts and 8-mm bolt in crisscross pattern in several stepsRemove th head cover bolts and the cyl inder head cover
Remove the gasket and the dowe pins
ROCKER ARM REMOVAL
Remove the cylinder head cover (page 8-til Do no clamp rhe marmg surface
SUB -ROCKER ARM SHAFTS