ENGINE
3-7
EAM20135
ENGINE
EAM30226
ADJUSTING THE VALVE CLEARANCE
TIP
•
This section is intended for those who have ba-
sic knowledge and skill concerning the servic-
ing of Yamaha motorcycles (e.g., Yamaha
dealers, service engineers, etc.). Those who
have little knowledge and skill concerning ser-
vicing are requested not to undertake inspec-
tion, adjustment, disassembly, or reassembly
only by reference to this manual. It may lead to
servicing trouble and mechanical damage.
•
Make sure that the valve clearance is checked
or adjusted while the engine is cold (at room
temperature).
•
While the valve clearance is checked or adjust-
ed, make sure that the piston is positioned in
the top dead center (TDC).
1. Remove:
•
Seat
•
Side cover (left/right)
•
Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 4-1.
•
Fuel tank
Refer to “FUEL TANK” on page 7-1.
•
ECU
2. Remove:
•
Spark plug
•
Cylinder head cover
Refer to “CAMSHAFT” on page 5-14.
3. Remove:
•
Timing mark accessing screw “1”
•
Crankshaft end accessing screw “2”
•
O-ring
4. Check:
•
Valve clearance
Out of specification
Regulate.
a. Turn the crankshaft counterclockwise with
a wrench.
b. Align the top dead center (TDC) mark “a”
on the generator rotor with the alignment
mark “b” on the crankcase cover.
TIP
Check that the alignment mark “c” on the cam-
shaft sprocket and the alignment mark “d” on the
intake camshaft sprocket are aligned with the
edge of the cylinder head.
c. Measure the valve clearance using a
thickness gauge “1”.
TIP
Record the measured reading if the clearance is
incorrect.
1
2
Valve clearance (cold)
Intake
0.12–0.19 mm (0.0047–0.0075 in)
Exhaust
0.17–0.24 mm (0.0067–0.0094 in)
Thickness gauge
90890-03268
Feeler gauge set
YU-26900-9
b
a
d
c
Summary of Contents for WR250FM 2021
Page 5: ...EAM20093 YAMAHA MOTOR CORPORATION U S A WR MOTORCYCLE LIMITED WARRANTY...
Page 8: ......
Page 10: ......
Page 52: ...MOTORCYCLE CARE AND STORAGE 1 40...
Page 62: ...ELECTRICAL SPECIFICATIONS 2 9 Radiator fan motor fuse 5 0 A Spare fuse 15 0 A...
Page 70: ...CABLE ROUTING DIAGRAM 2 17 EAM20152 CABLE ROUTING DIAGRAM Frame and engine left side view...
Page 72: ...CABLE ROUTING DIAGRAM 2 19 Frame and engine right side view...
Page 74: ...CABLE ROUTING DIAGRAM 2 21 Handlebar front view...
Page 76: ...CABLE ROUTING DIAGRAM 2 23 Frame and engine top view...
Page 78: ...CABLE ROUTING DIAGRAM 2 25 Frame and battery top view...
Page 80: ...CABLE ROUTING DIAGRAM 2 27 Rear brake right side view...
Page 82: ...CABLE ROUTING DIAGRAM 2 29 Front brake front view and right side view...
Page 84: ...CABLE ROUTING DIAGRAM 2 31 Taillight top view and right side view...
Page 86: ...CABLE ROUTING DIAGRAM 2 33...
Page 203: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 3 1 Oil filter element 2 Oil pump...
Page 204: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 4 1 Intake camshaft 2 Exhaust camshaft...
Page 278: ...TRANSMISSION 5 78...
Page 288: ...WATER PUMP 6 9...
Page 298: ...THROTTLE BODY 7 9...
Page 301: ......
Page 302: ...IGNITION SYSTEM 8 1 EAM20142 IGNITION SYSTEM EAM30277 CIRCUIT DIAGRAM...
Page 306: ...ELECTRIC STARTING SYSTEM 8 5 EAM20143 ELECTRIC STARTING SYSTEM EAM30279 CIRCUIT DIAGRAM...
Page 312: ...CHARGING SYSTEM 8 11 EAM20144 CHARGING SYSTEM EAM30282 CIRCUIT DIAGRAM...
Page 315: ...CHARGING SYSTEM 8 14...
Page 316: ...SIGNALING SYSTEM 8 15 EAM20154 SIGNALING SYSTEM EAM30348 CIRCUIT DIAGRAM...
Page 320: ...LIGHTING SYSTEM 8 19 EAM20153 LIGHTING SYSTEM EAM30346 CIRCUIT DIAGRAM...
Page 323: ...LIGHTING SYSTEM 8 22...
Page 324: ...COOLING SYSTEM 8 23 EAM20155 COOLING SYSTEM EAM30350 CIRCUIT DIAGRAM...
Page 327: ...COOLING SYSTEM 8 26...
Page 328: ...FUEL INJECTION SYSTEM 8 27 EAM20145 FUEL INJECTION SYSTEM EAM30284 CIRCUIT DIAGRAM...
Page 353: ...FUEL INJECTION SYSTEM 8 52...
Page 354: ...FUEL PUMP SYSTEM 8 53 EAM20146 FUEL PUMP SYSTEM EAM30287 CIRCUIT DIAGRAM...
Page 388: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 15...
Page 398: ...CHASSIS 10 9...
Page 400: ......
Page 402: ......
Page 403: ...WR250FM 2021 WIRING DIAGRAM BAK 2819U 11_W D indd 1 2020 07 01 12 01 28...
Page 404: ...WR250FM 2021 WIRING DIAGRAM BAK 2819U 11_W D indd 2 2020 07 01 12 01 28...