2006-2009 Honda TRX680 (TRX 680 FA-FGA) Factory Service Manual, Page 522Get this manual
IGNITION SYSTEM
IGNITION TIMING
Remove the fight side cover (page 36)Start the engine and warm It up to operatmq te peratureSto the engine and rem ove the timing ho le cap fr om he rear crankcase cover
connect th timing light and tacho meterStart tne enginelet it id le and chec th igni tion
The ig ni tio timing is cor rect jf the ark on the flywh eel ali gns it he mde mark on th rear crankc ase cover et idleIncrease he engine speed and make sure he ma rk beg in to move