Yamaha YZ450F(T) Owner's Service Manual page 240

IGNITION TIMING CHECK
IGNITION TIMING CHECK
1. Remove:
• Timing plug 1
2. Attach:
• Timing light
To the ignition coil lead
(orange lead 1).
Timing light:
3. Adjust:
• Engine idling speed
Refer to "IDLE SPEED ADJUSTMENT".
4. Check:
• Ignition timing
Visually check the stationary pointer a is
within the firing range b on the rotor.
Incorrect firing range → Check rotor and
pickup assembly.
5. Install:
• Timing plug
3 - 47
INSP
ADJ
YM-33277-A/90890-03141