2015 YAMAHA WR 250F Owners Manual

CHASSIS
3-33
EAS2GB2118CHECKING THE SWINGARM OPERATION
1. Check:
• Swingarm smooth action
• Swingarm free play
Refer to “SWINGARM” on page 5-64.
EAS2GB2119CHECKING THE REAR SUSPENSION
1. Stand the vehicle upright on a level surface.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Check:
• Rear shock absorber assembly
Gas leaks/oil leaks  Replace the rear
shock absorber assembly.
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-57.
3. Check:
• Rear shock absorber assembly smooth ac-
tion
• Rear suspension link smooth action
Sit astride the seat and shake your body up
and down several times to check whether
the rear shock absorber assembly operates
smoothly.
Unsmooth operation  Correct or replace.
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-57.
EAS2GB2120ADJUSTING THE REAR SHOCK ABSORB-
ER ASSEMBLY
Use a suitable stand to raise the rear wheel off
the ground.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.Spring preload
ECA
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Remove:
• Rear frame
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-57.
2. Adjust:
• Spring preload
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a. Loosen the locknut “1”.
b. Loosen the adjuster “2” until there is some
clearance between the spring and the ad-
juster.
c. Measure the spring free length “a”.
d. Turn the adjuster in the direction of “b” or “c”
to make an adjustment.
Direction “b”
Spring preload is increased (suspen-
sion is harder).
Direction “c”
Spring preload is decreased (suspen-
sion is softer).
Spring installed length “d”
Minimum
Position in which the spring is
turned in 1.5 mm (0.06 in) from
its free length.
STD
Position in which the spring is
turned in 10 mm (0.39 in) from its
free length.
Maximum
Position in which the spring is
turned in 18 mm (0.71 in) from its
free length.

CHASSIS
3-34
TIP
• Be sure to remove all dirt and mud from
around the locknut and adjusting ring before
adjustment.
• The length of the spring (installed) changes
1.5 mm (0.06 in) per turn of the adjusting ring.
e. Tighten the locknut.
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3. Install:
• Rear frame
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-57.
Rebound damping force
ECA
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Adjust:
• Rebound damping force
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the adjuster “1” in the direction of “a” or
“b” to make an adjustment.
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High compression dampingECA
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Adjust:
• High compression damping
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the adjuster “1” in the direction of “a” or
“b” to make an adjustment. Locknut
30 Nm (3.0 m·kgf, 22 ft·lbf)
Direction “a”
Rebound damping force is increased
(suspension is harder).
Direction “b”
Rebound damping force is decreased
(suspension is softer).
c
b
d
T R..
Rebound damping force
Maximum
Turn it in finger-tight.
STD
Turn it out by 14 clicks.*
Minimum
Turn it out by 30 clicks.*
* With the adjuster fully turned
Direction “a”
High compression damping force is in-
creased (suspension is harder).
Direction “b”
High compression damping force is de-
creased (suspension is softer).
High compression damping
Maximum
Turn it in finger-tight.
STD
Turn it out by 1 1/4 turns.*
Minimum
Turn it out by two turns.*
* With the adjuster fully turned
a
b
1

CHASSIS
3-35
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Low compression dampingECA
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Adjust:
• Low compression damping
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the adjuster “1” in the direction of “a” or
“b” to make an adjustment.
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EAS2GB2121
CHECKING THE TIRES
1. Measure:
• Tire pressure
Out of specification  Regulate.
TIP
• Check the tire while it is cold.
• Loose bead stoppers allow the tire to slip off
its position on the rim when the tire pressure
is low.
• If the tire valve stem is found tilted, the tire is
considered to be slipping off its position. Cor-
rect the tire position.
EAS2GB2122CHECKING AND TIGHTENING THE
SPOKES
1. Check:
• Spokes
Bend/damage  Replace.
Loose  Tighten.
TIP
A tight spoke will emit a clear, ringing tone; a
loose spoke will sound flat. Direction “a”
Low compression damping force is in-
creased (suspension is harder).
Direction “b”
Low compression damping force is de-
creased (suspension is softer).
Low compression damping
Maximum
Turn it in finger-tight.
STD
Turn it out by 10 clicks.*
Minimum
Turn it out by 20 clicks.*
* With the adjuster fully turned in
1
a b
1ba
Tire air pressure (measured on cold
tires)
100 kPa (1.00 kgf/cm
2, 15 psi)

CHASSIS
3-36
2. Tighten:
• Spokes
Use a spoke nipple wrench “1” for tighten-
ing.
TIP
• Do not give a half turn (180 °) or more for one
tightening.
• Make sure that tightening after a break-in is
done until the initial looseness in nipples dis-
appears.
• Make sure that tightening is done in stages,
not at a time.
EAS2GB2123CHECKING THE WHEELS
1. Check:
• Wheel(s)
Damage/out-of-round  Replace.
EWA
WARNING
Never attempt to make any repairs to the
wheel.
TIP
After replacing a tire or a wheel, always bal-
ance the wheel.
EAS2GB2124CHECKING THE WHEEL BEARINGS
1. Check:
• Wheel bearings
Refer to “CHECKING THE FRONT WHEEL”
on page 5-5 and “CHECKING THE REAR
WHEEL” on page 5-10.
EAS2GB2125
CHECKING AND ADJUSTING THE STEER-
ING HEAD
1. Use a suitable stand to raise the front wheel
off the ground.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Check:
• Steering head
Grasp the bottom of the front fork legs and
gently rock the front fork.
Blinding/looseness  Adjust the steering
head.
3. Remove:
• Handlebar
Refer to “HANDLEBAR” on page 5-33.
• Upper bracket
Refer to “STEERING HEAD” on page 5-53.
4. Adjust:
• Steering head
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the washer “1”.
b. After loosening the ring nut “2” with a steer-
ing nut wrench “3”, tighten it to the specified
torque.
TIP
• Set the torque wrench at a right angle to the
steering nut wrench.
• Move the steering to the left and right a couple
of times to check that it moves smoothly. Spoke nipple wrench (6–7)
90890-01521
Spoke nipple wrench (6–7)
YM-01521
Spokes
2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
1
T R..
1
3
2

CHASSIS
3-37
c. Turn the front fork to the right and left a few
times, and make sure that the steering ro-
tates smoothly. If it does not turn smoothly,
remove the lower bracket and check the up-
per and lower bearings.
Refer to “STEERING HEAD” on page 5-53.
d. Loosen the ring nut fully turn and then tight-
en it to specification with a steering nut
wrench.
EWA
WARNING
Do not overtighten the lower ring nut.
e. Check the steering head for looseness or
binding by turning the front fork all the way in
both directions. If any binding is felt, remove
the lower bracket and check the upper and
lower bearings.
Refer to “STEERING HEAD” on page 5-53.
f. Install the washer “1”.
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5. Install:
• Upper bracket
Refer to “STEERING HEAD” on page 5-53.
• Handlebar
Refer to “HANDLEBAR” on page 5-33.
EAS2GB2126
CHECKING AND LUBRICATING THE CA-
BLES
The following procedure applies to all of the in-
ner and outer cables.
EWA
WARNING
Damaged outer cable may cause the cable
to corrode and interfere with its movement.
Replace damaged outer cable and inner ca-
bles as soon as possible.
1. Check:
• Outer cable
Damage  Replace.
2. Check:
• Cable operation
Rough movement  Lubricate.
TIP
Hold the cable end upright and pour a few
drops of lubricant into the cable sheath or use
a suitable lubricating device.
EAS2GB2127LUBRICATING THE LEVERS
1. Lubricate the pivoting points and metal-to-
metal moving parts of the following parts.
•Brake lever
• Clutch lever
EAS2GB2128LUBRICATING THE PEDAL
1. Lubricate the pivoting point and metal-to-
metal moving parts of the pedal. Steering nut wrench
90890-01403
Exhaust flange nut wrench
YU-A9472
Ring nut (initial tightening torque)
38 Nm (3.8 m·kgf, 27 ft·lbf)
Ring nut (final tightening torque)
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
T R..
T R..
1
Recommended lubricant
Engine oil or a suitable cable lu-
bricant
Recommended lubricant
Silicone grease
Recommended lubricant
Lithium-soap-based grease
Recommended lubricant
Lithium-soap-based grease

CHASSIS
3-38
EAS2GB2129LUBRICATING THE DRIVE CHAIN
The drive chain consists of many interacting
parts. If the drive chain is not maintained prop-
erly, it will wear out quickly. Therefore, the drive
chain should be serviced, especially when the
vehicle is used in dusty areas.
This vehicle has a drive chain with small rubber
O-rings between each side plate. Steam clean-
ing, high-pressure washing, certain solvents,
and the use of a coarse brush can damage
these O-rings. Therefore, use only kerosene to
clean the drive chain. Wipe the drive chain dry
and thoroughly lubricate it with engine oil or
chain lubricant that is suitable for O-ring chains.
Do not use any other lubricants on the drive
chain since they may contain solvents that
could damage the O-rings.
EAS2GB2130LUBRICATING THE SIDESTAND
Lubricate the pivoting point and metal-to-metal
moving parts of the sidestand.
EAS2GB2131CHECKING THE CHASSIS FASTENERS
Make sure that all nuts, bolts, and screws are
properly tightened.
Refer to “CHASSIS TIGHTENING TORQUES”
on page 2-17.Recommended lubricant
Chain lubricant suitable for O-
ring chains
Recommended lubricant
Lithium-soap-based grease

ELECTRICAL SYSTEM
3-39
EAS2GB2132
ELECTRICAL SYSTEM
EAS2GB2133CHECKING THE SPARK PLUG
1. Remove:
• Seat
• Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
• Fuel tank “1”
Refer to “FUEL TANK” on page 8-1.
ECA
NOTICE
Do not use too much force to pull the hose.
TIP
Remove the fuel tank, turn this 180 ° clockwise,
and put it in the frame “2” as shown.
2. Remove:
• Spark plug cap
• Spark plug
Refer to “CAMSHAFT” on page 6-11.
ECA
NOTICE
In order not to allow the dirt accumulated
around the spark plug to drop from the
spark plug hole into the cylinder, clean it be-
fore removing the spark plug.
3. Check:
• Spark plug type
Wrong type  Replace.
4. Check:
• Electrode
Damage/wear  Replace the spark plug.
• Insulator
Abnormal color  Replace the spark plug.
Normal color is medium-to-light tan.5. Clean:
• Spark plug
(with a spark plug cleaner or a wire brush)
6. Measure:
• Spark plug gap “a”
Out of specification  Adjust the spark plug
gap.
7. Install:
• Spark plug
TIP
Before installing the spark plug, clean the spark
plug and gasket surface.
8. Install:
• Spark plug cap
• Fuel tank
• Air scoop (left/right)
• Seat
• Side cover (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
EAS2GB2134CHECKING THE IGNITION TIMING
1. Remove:
• Timing mark accessing screw “1”
Manufacturer/model
NGK/LMAR8G
1
1
2
Spark plug gap
0.7–0.8 mm (0.028–0.031 in)
Spark plug
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
T R..
1

ELECTRICAL SYSTEM
3-40
2. Attach:
• Timing light “1”
• Digital tachometer “2”
To the high tension code “3”.
3. Adjust:
• Engine idling speed
Refer to “ADJUSTING THE ENGINE
IDLING SPEED” on page 3-18.
4. Check:
• Ignition timing
Check whether the alignment mark “a” on
the left crankcase cover is within the firing
range “b” on the rotor.
Incorrect firing range  Check rotor and
Crankshaft position sensor.
5. Install:
• Timing mark accessing screw
EAS2GB2135
CHECKING AND CHARGING THE BATTERY
Refer to “CHECKING AND CHARGING THE
BATTERY” on page 9-69.
EAS2GB2136REPLACING THE HEADLIGHT BULBEWA
WARNING
Since the headlight bulb gets extremely hot,
keep flammable products and your hands
away from the bulb until it has cooled down.
1. Remove:
• Headlight unit bolt “1”
TIP
After you have removed the headlight unit
bolts, lift and remove the headlight unit.
2. Remove:
• Headlight coupler “1”
• Bulb cover “2”
3. Remove:
• Headlight bulb “1” Timing light
90890-03141
Timing light
YU-03141
Digital tachometer
90890-06760
Digital tachometer
YU-39951-B
Timing mark accessing screw
6 Nm (0.6 m·kgf, 4.3 ft·lbf)
2
1
3
ba
T R..
11
1
2
1