2017 YAMAHA WR 250F sensor

FRONT FORK
5-51
TIP
Use the cap bolt ring wrench “2” to tighten the
damper assembly.
3. Adjust:
• Front fork top end “a”
4. Tighten:
• Pinch bolt (upper bracket) “1”
• Pinch bolt (lower bracket) “2”
EWA
WARNING
Tighten the lower bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.5. Install:
• Speed sensor lead “1”
• Plate 1 “2”
(to the right front fork protector)
TIP
Install the speed sensor lead so that its paint “a”
directs as shown and align the bottom “b” of the
plate 1 with the same paint.
6. Install:
• Speed sensor lead “1”
• Plate 2 “2”
(to the right front fork protector)
TIP
Install the plate 2 in the direction as shown. Cap bolt ring wrench
90890-01501
Cap bolt ring wrench
YM-01501
Front fork top end (standard) “a”
5 mm (0.20 in)
Upper bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
Lower bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
2
1
a
T R..
T R..
Plate 1 bolt
3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
Plate 2 screw
0.5 Nm (0.05 m·kgf, 0.36 ft·lbf)
21
T R..
1 2
a b
T R..
1
212

STEERING HEAD
5-57
8. Install:
• Steering stem nut “1”
TIP
Apply the lithium-soap-based grease to the
contact surface of the steering stem nut when
installing.
9. After tightening the nut, check the steering
for smooth movement. If not, adjust the
steering by loosening the steering ring nut
little by little.
10.Adjust:
• Front fork top end “a”11.Tighten:
• Pinch bolt (upper bracket) “1”
• Pinch bolt (lower bracket) “2”
EWA
WARNING
Tighten the lower bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
12.Install:
• Speed sensor lead holder “1”
• Speed sensor lead clamp “2”
TIP
• Insert the end of the speed sensor lead holder
in the hole in the lower bracket “a”.
• Install so that the marking “b” on the speed
sensor lead aligns with the speed sensor lead
holder edge.
• Install the speed sensor lead clamp while in-
serting it in the hole “c” in the speed sensor
lead holder. Steering stem nut
145 Nm (14.5 m·kgf, 105 ft·lbf)
Front fork top end (standard) “a”
5 mm (0.20 in)
T R..
a
Upper bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
Lower bracket pinch bolts
21 Nm (2.1 m·kgf, 15 ft·lbf)
Speed sensor lead holder bolt
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
Speed sensor lead clamp bolt
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
T R..
T R..
21
T R..

ENGINE REMOVAL
6-3
Removing the electronic parts
Order Part name Q’ty Remarks
Use a suitable stand to raise the front wheel
off the ground.
Seat Refer to “GENERAL CHASSIS” on page 5-1.
Side cover (left/right) Refer to “GENERAL CHASSIS” on page 5-1.
Air scoop (left/right) Refer to “GENERAL CHASSIS” on page 5-1.
Fuel tank Refer to “FUEL TANK” on page 8-1.
Air filter case cover
1 Rectifier/regulator 1
2ECU 1
3 Ignition coil 1
4 Neutral switch 1
5 AC magneto coupler 1 Disconnect.
6 Crankshaft position sensor coupler 1 Disconnect.
7 Coolant temperature sensor coupler 1 Disconnect.
For installation, reverse the removal proce-
dure.
T.R.
T.R.
T.R.T.R.
7 3
6
5
142
LT
New
LS

CYLINDER HEAD
6-20
EAS2GBB244
CYLINDER HEAD
Removing the cylinder head
Order Part name Q’ty Remarks
Seat Refer to “GENERAL CHASSIS” on page 5-1.
Side cover (left/right) Refer to “GENERAL CHASSIS” on page 5-1.
Air scoop (left/right) Refer to “GENERAL CHASSIS” on page 5-1.
Fuel tank Refer to “FUEL TANK” on page 8-1.
Exhaust pipe and silencer Refer to “ENGINE REMOVAL” on page 6-1.
Radiator hose Disconnect.
Coolant temperature sensor coupler Disconnect.
Throttle body Refer to “THROTTLE BODY” on page 8-7.
Camshaft Refer to “CAMSHAFT” on page 6-12.
Upper engine bracket Refer to “ENGINE REMOVAL” on page 6-1.
1 Nut (cylinder head) 2
2 Bolt (cylinder head) 4
3 Cylinder head 1
4 Cylinder head gasket 1
6
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.
33 Nm (3.3 m kgf, 24 ft Ibf)T.R.
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.

GENERATOR AND STARTER CLUTCH
6-67
11 Woodruff key 1
12 Starter clutch 1
13 Starter clutch drive gear 1
14 Crankshaft position sensor 1
15 Stator 1
For installation, reverse the removal proce-
dure.
Removing the generator
Order Job/Parts to remove Q’ty Remarks
T R..
T R..
6
611
9
8
7
2
3
1
14
4 5
12
10
13
T R..
T R..
T R..LTT R..
T R..
15

GENERATOR AND STARTER CLUTCH
6-69
• Crankshaft position sensor “3”
• Holder “4”
• Crankshaft position sensor bolt “5”
TIP
• Pass the AC magneto lead “6” and crankshaft
position sensor lead “7” under the holder as
shown.
• Tighten the stator bolt using the T25 bit.
• Apply the sealant to the grommet of the AC
magneto lead.
2. Install
• Starter clutch drive gear “1”
TIP
Apply the engine oil on the starter clutch drive
gear inner circumference.3. Install:
• Starter clutch “1”
To generator rotor “2”.
EAS2GBB309INSTALLING THE GENERATOR
1. Install:
• Woodruff key “1”
• Generator rotor “2”
TIP
• Clean the contact surfaces of the tapered por-
tions of the crankshaft and generator rotor.
• When installing the woodruff key, make sure
that its flat surface “a” is in parallel with the
crankshaft center line “b”.
• When installing the generator rotor, align the
keyway “c” of the generator rotor with the
woodruff key. Stator bolt
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
LOCTITE®
Crankshaft position sensor bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Yamaha bond No.1215
90890-85505
(Three bond No.1215®)
T R..
T R..
6
7
1
3
22
5
5
4LT
Starter clutch bolt
16 Nm (1.6 m·kgf, 12 ft·lbf)
LOCTITE®
21
LT
T R..
2 C1 1
1a b

RADIATOR
7-2
4 Right radiator 1
5 Radiator hose 2 1
6 Radiator hose 3 1
7 Radiator hose 4 1
8 Radiator pipe 2 1
9 Radiator breather hose 1
10 Left radiator 1
11 Radiator hose 1 1
12 Radiator pipe 1 1
13 Coolant temperature sensor 1
For installation, reverse the removal proce-
dure.
Removing the radiator
Order Part name Q’ty Remarks
12
13
New
New
New
LS
LS
3
458 Nm (0.8 m kgf, 5.8 ft Ibf)T.R.
6
7
89
10
112
2
2
2 22 2
1 1

8
FUEL SYSTEM
FUEL TANK...................................................................................................... 8-1
REMOVING THE FUEL TANK ................................................................... 8-3
REMOVING THE FUEL PUMP .................................................................. 8-3
CHECKING THE FUEL PUMP BODY........................................................ 8-3
INSTALLING THE FUEL PUMP ................................................................. 8-3
REMOVING THE FUEL SENDER.............................................................. 8-4
CHECKING THE FUEL SENDER .............................................................. 8-4
INSTALLING THE FUEL SENDER ............................................................ 8-4
INSTALLING THE FUEL TANK.................................................................. 8-4
CHECKING THE FUEL PRESSURE ......................................................... 8-5
CHECKING THE DAMPER ........................................................................ 8-6
CHECKING AND REPLACING THE PROTECTOR .................................. 8-6
THROTTLE BODY............................................................................................ 8-7
CHECKING THE INJECTOR ................................................................... 8-10
CHECKING THE THROTTLE BODY ....................................................... 8-10
CHECKING THE THROTTLE BODY JOINT ............................................ 8-10
ADJUSTING THE THROTTLE POSITION SENSOR............................... 8-11