2005-2009 Honda TRX400EX/TRX400X Service Manual, Page 140Get this manual
CYLINDER HEADVALVE Clean the mating surfaces of the cylinder head and cover th oroug hly, being carefu not to damage themPour engine oi into th oil pockets in the cylinder headA pply molybdenum oil solution to th camshfat cam lobes and journals
Install the dowel pins and new gasket
App ly mo lybdenum oil solution to the slipper su rfaces of the rocker arms and sub-rocker arms in the cy linder head cover