2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 210Get this manual
CYLINDER HEADVALVE
CYLINDER HEAD REMOVAL
Remove the camshaft holder (page 11-8)Remove the following:exhaust system (page 3-10)carburetor ('04'05: page 7-6, After '05: page 8-7)thermostat (page 9-8)engine coolant temperature (ECT) sensor connectorECT sensor CONNECTOR ECTSENSOR