2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 102Get this manual
LUBRICATION SYSTEM ('04'05)
OIL STRAINERPRESSURE RELIEF VALVE
REMOVAL
Remove the balancer shaft (page 15-7)Remove the snap ring and oil pump driven gear from the oil pump shaft
OIL PUMP DRIVEN GEAR Remove the bolt, set plate and the engine oil pressure relief valveBOLT