2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 316Get this manual
CRANKCASETRANSMISSIONCRANKSHAFTBALANCER ('04'05) Apply grease to new crankshaft oil seal lip and install it into the right crankcaseInstall the crankshaft (page 15-19)
CRANKCASE ASSEMBLY
Install the reed valve into the right crankcase
REED VALVE Dip oil pump inner and outer rotors in clean engine oilInstall the oil pump shaft, inner and outer rotors into the left crankcaseOIL PUMP SHAFT