2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 491Get this manual
ELECTRIC STARTER (TRX450ER)
The coil may be damaged if the magnet pulls the armature against the caseWith the commutator bar facing the groove in the motor case, install the armature while holding the armature tightly to keep the magnet of the case from pulling the armature against itGROOVE
ARMATURE Install the same number of shims in the same locations as noted during disassemblyInstall new seal ring onto the motor caseApply thin coat of grease to the armature shaft endInstall the rear cover while pushing the brushes into the brush holder and aligning the brush holder tab with the case groove (index marks)REAR COVER SEAL RING