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ENGINE
3-11
EAM30412
CHECKING THE ENGINE IDLING SPEED
TIP
•
Because the air pressure is lower at high alti-
tudes, the air-fuel mixture will become richer. If
the idling speed is low, turn the idle screw
clockwise to increase the speed before the ad-
justment.
•
Before adjusting the engine idling speed, make
sure that the air filter element is not clogged,
the engine compression is proper, and the
throttle grip free play is proper.
•
Adjust the engine idling speed with the starter
knob pulled in completely.
1. Start the engine, and warm this up until the oil
has reached the specified temperature.
2. Measure the coolant temperature using the
Yamaha diagnostic tool.
3. Install:
•
Digital tachometer
TIP
Get the high tension cord “1” of the ignition coil
pinched in the detector “a” of the digital tachom-
eter.
4. Measure:
•
Engine idling speed
Out of specification
Regulate.
5. Adjust:
•
Engine idling speed
a. Turn the idle screw “1” to make an adjust-
ment.
EAM30475
CHECKING THE THROTTLE GRIP
TIP
Prior to adjusting throttle grip free play, the en-
gine idling speed should be adjusted.
1. Check:
•
Throttle grip free play “a”
Out of specification
Regulate.
Yamaha diagnostic tool USB (US)
90890-03269
Yamaha diagnostic tool (A/I)
90890-03264
FI diagnostic tool sub–lead
90890-03212
FI diagnostic tool sub–lead
YU-03212
OBD/ GST Leadwire kit
90890-03249
Coolant temperature
70–80
C (158–176
F)
Digital tachometer
90890-06760
Digital tachometer
YU-39951-B
Engine idling speed
1900–2100 r/min
Throttle grip free play
3.0–6.0 mm (0.12–0.24 in)
1
a
a
a
1
1
1
1
Summary of Contents for YZ450FN 2022
Page 6: ...EAM20162 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY...
Page 10: ......
Page 44: ...MOTORCYCLE CARE AND STORAGE 1 32...
Page 61: ...TIGHTENING TORQUES 2 16...
Page 62: ...CABLE ROUTING DIAGRAM 2 17 EAM20152 CABLE ROUTING DIAGRAM Frame and engine left side view...
Page 64: ...CABLE ROUTING DIAGRAM 2 19 Frame and engine right side view...
Page 66: ...CABLE ROUTING DIAGRAM 2 21 Handlebar front view...
Page 68: ...CABLE ROUTING DIAGRAM 2 23 Frame and engine top view...
Page 70: ...CABLE ROUTING DIAGRAM 2 25 Frame and battery top view...
Page 72: ...CABLE ROUTING DIAGRAM 2 27 Rear brake right side view...
Page 74: ...CABLE ROUTING DIAGRAM 2 29...
Page 112: ...ELECTRICAL SYSTEM 3 36...
Page 148: ...REAR BRAKE 4 34 system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM on page 3 25...
Page 189: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 3 1 Connecting rod 2 Oil nozzle 3 Crankshaft...
Page 191: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 5 1 Oil filter element 2 Oil pump 3 Oil strainer...
Page 270: ...WATER PUMP 6 9...
Page 280: ...THROTTLE BODY 7 9...
Page 287: ...IGNITION SYSTEM 8 6...
Page 288: ...ELECTRIC STARTING SYSTEM 8 7 EAM20143 ELECTRIC STARTING SYSTEM EAM30279 CIRCUIT DIAGRAM...
Page 292: ...CHARGING SYSTEM 8 11 EAM20144 CHARGING SYSTEM EAM30282 CIRCUIT DIAGRAM...
Page 295: ...CHARGING SYSTEM 8 14...
Page 296: ...FUEL INJECTION SYSTEM 8 15 EAM20145 FUEL INJECTION SYSTEM EAM30284 CIRCUIT DIAGRAM Sb P Y W...
Page 319: ...FUEL INJECTION SYSTEM 8 38...
Page 320: ...FUEL PUMP SYSTEM 8 39 EAM20146 FUEL PUMP SYSTEM EAM30287 CIRCUIT DIAGRAM...
Page 350: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 15...
Page 360: ...CHASSIS 10 9...
Page 362: ......
Page 364: ......
Page 366: ...YZ450FN 2022 WIRING DIAGRAM B2W 2819U 12_W D indd 2 2021 01 26 11 09 29...