Yamaha WR450F(S) Owner's Service Manual page 278

IGNITION TIMING CHECK
1
1
IGNITION TIMING CHECK
1. Remove:
Timing plug 1
G
2. Attach:
Timing light
G
Inductive tachometer
G
To the ignition coil lead (orange lead
1).
Timing light:
YM-33277-A/90890-03141
3. Adjust:
Engine idling speed
G
Refer to "IDLE SPEED ADJUST-
MENT".
4. Check:
Ignition timing
G
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
G
3 - 49
INSP
ADJ