Yamaha YZ450FX 2021 Owner's Service Manual page 111

EAM20137
ELECTRICAL SYSTEM
EAM30256
CHECKING AND CHARGING THE BATTERY
Refer to "CHECKING AND CHARGING THE
BATTERY" on page 8-50.
EAM30505
CHECKING THE FUSES
Refer to "CHECKING THE FUSES" on page
8-49.
EAM30255
CHECKING THE IGNITION TIMING
1. Remove:
• Timing mark accessing screw "1"
2. Attach:
• Timing light "1"
• Digital tachometer "2"
(to the high tension cord "3")
Timing light
90890-03141
Timing light
YU-03141
Digital tachometer
90890-06760
Digital tachometer
YU-39951-B
1
3. Adjust:
• Engine idling speed
Refer to "CHECKING THE ENGINE IDLING
SPEED" on page 3-11.
4. Check:
• Ignition timing
Check whether the alignment mark "a" on the
left crankcase cover is within the firing range
"b" on the generator rotor.
Incorrect firing range  Check generator ro-
tor and crankshaft position sensor.
5. Install:
• Timing mark accessing screw
1
3 3
2 2
3-35
ELECTRICAL SYSTEM
b b
a a
Timing mark accessing screw
6 N·m (0.6 kgf·m, 4.4 lb·ft)