1987-2009 Yamaha ATV YFM350X Warrior Raptor Service Manual, Page 336Get this manual
IGNITION SYSTEM Spark plug gap: 0.80.9 mm (0.0310.035 in) CORRECT For USA and CDN 4.Ignition spark gap
INCORRECT
Repair or replace the spark plug
Disconnect the spark plug cap from the spark plugConnect the dynamic spark tester as shownTurn the main switch to "ON"Check the ignition spark gapCrank the engine by pushing the starter switch, and increase the spark gap until misfiring occursMinimum spark gap: 6.0 mm (0.24 in)
2 Spark plug cap Spark plug