2004-2005 Honda TRX450R Factory Sevice Manual, Page 161Get this manual
CYLINDER HEADIVALVE
CYLINDER HEAD COVER INSTALLATION
Clean he mating surfaces of the cylinder head and cover tho rough ly, being caref ul not to damage them Apply adhesive to the gasket roove in the cylinder head cover and install new asketInstall new rubber seal into spa rk plug hol eInstall th head cover by alig ning th plug hol it he lug sleeve, being caref ul not to da mage he rubber seal