2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 492Get this manual
ELECTRIC STARTER (TRX450ER) Coat new O-ring with oil and install it into the starter motor groove
INSTALLATION
Install the starter motor onto the crankcaseInstall the ground cable and mounting boltsInstall the starter motor cable and terminal nut onto the motor terminalTighten the nut securelyInstall the rubber cap over the motor terminal properlySTARTER MOTOR