THROTTLE BODY
7-7
EAM30271
CHECKING THE INJECTOR
1. Check:
•
Injector
Obstruction
Replace, and check the fuel
pump and the fuel injection system.
Refer to “FUEL INJECTION SYSTEM” on
page 8-17.
Deposits
Replace.
Damage
Replace.
2. Check:
•
Injector resistance
Refer to “CHECKING THE INJECTOR” on
page 8-59.
EAM30272
CHECKING THE THROTTLE BODY
1. Check:
•
Throttle body
Cracks/damage
Replace.
2. Check:
•
Fuel passages
Obstructions
Clean.
NOTICE
ECA26070
• Before removing the throttle body, clean
the area around the throttle body to prevent
dirt and other foreign material from falling
into the engine.
• If the throttle body is subject to strong
shocks or dropped during cleaning, re-
place it.
• Do not use any caustic carburetor cleaning
solution.
• Do not directly push the throttle valves to
open them.
• Do not loosen the throttle valve stopper
screw “1”, throttle valve pulley nut “2”,
throttle valve screw “3” or starter knob nut
“4”. A loss of performance may occur.
• Do not use compressed air to clean the
throttle body. Foreign materials may ad-
here to the intake air pressure sensor pas-
sage “a” and fuel injector “b” in the throttle
body.
3. Check:
•
Idle screw “1” passage “a”
Obstruction
Blow out with compressed air.
EAM30268
CHECKING THE FUEL PRESSURE
1. Check:
•
Fuel pressure
a. Remove the side cover (left/right), the seat
and the air scoop (left/right).
Refer to “GENERAL CHASSIS” on page
4-1.
2
1
3
b
a
4
a
1
Summary of Contents for YZ250FX 2021
Page 6: ...EAM20162 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY ...
Page 10: ......
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 153: ...HANDLEBAR 4 39 Throttle grip free play 3 0 6 0 mm 0 12 0 24 in ...
Page 166: ...FRONT FORK 4 52 1 ...
Page 184: ...CHAIN DRIVE 4 70 ...
Page 189: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 3 1 Oil filter element 2 Oil pump ...
Page 190: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 4 1 Intake camshaft 2 Exhaust camshaft ...
Page 264: ...TRANSMISSION 5 78 ...
Page 274: ...WATER PUMP 6 9 ...
Page 284: ...THROTTLE BODY 7 9 ...
Page 287: ......
Page 288: ...IGNITION SYSTEM 8 1 EAM20142 IGNITION SYSTEM EAM30277 CIRCUIT DIAGRAM ...
Page 292: ...ELECTRIC STARTING SYSTEM 8 5 EAM20143 ELECTRIC STARTING SYSTEM EAM30279 CIRCUIT DIAGRAM ...
Page 296: ...CHARGING SYSTEM 8 9 EAM20144 CHARGING SYSTEM EAM30282 CIRCUIT DIAGRAM ...
Page 299: ...CHARGING SYSTEM 8 12 ...
Page 300: ...SIGNALING SYSTEM 8 13 EAM20154 SIGNALING SYSTEM EAM30348 CIRCUIT DIAGRAM ...
Page 304: ...FUEL INJECTION SYSTEM 8 17 EAM20145 FUEL INJECTION SYSTEM EAM30284 CIRCUIT DIAGRAM ...
Page 329: ...FUEL INJECTION SYSTEM 8 42 ...
Page 330: ...FUEL PUMP SYSTEM 8 43 EAM20146 FUEL PUMP SYSTEM EAM30287 CIRCUIT DIAGRAM ...
Page 362: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 15 ...
Page 372: ...CHASSIS 10 9 ...
Page 374: ......
Page 376: ......
Page 377: ...YZ250FXM 2021 WIRING DIAGRAM BAJ 2819U 11_WD indd 1 2020 06 29 15 46 05 ...
Page 378: ...YZ250FXM 2021 WIRING DIAGRAM BAJ 2819U 11_WD indd 2 2020 06 29 15 46 06 ...