2006-2012 Honda TRX90 TRX90EX/X Service Manual, Page 257Get this manual
IGNITION SYSTEM
IGNITION CONTROL MODULE (lCM)
REMOVAUINSTALLATION
Remove the ICM from the stay Disconnect the connectors to remove the ICMInstallation is in the reverse order of removal
IGNITION TIMING
Start the engine and warm it up to operating temperatureStop the eng ine and remove the timing hole cap from the left crankcase cover