2010 YAMAHA WR 125R check engine

PERIODIC MAINTENANCE AND ADJUSTMENT
6-14
6
EAUM1911
Adjusting the engine idling
speed The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm before
making this adjustment.TIPA diagnostic tachometer is needed to
make this adjustment.1. Attach the tachometer to the spark
plug lead.
2. Check the engine idling speed
and, if necessary, adjust it to spec-
ification by turning the idle adjust-
ing screw. To increase the engine
idling speed, turn the screw in di-
rection (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
TIPIf the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
EAU48430
Adjusting the throttle cable
free play The throttle cable free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.TIPThe engine idling speed must be cor-
rectly adjusted before checking and ad-
justing the throttle cable free play.1. Slide the rubber cover back.
2. Loosen the locknut.
1. Idle adjusting screwEngine idling speed:
1400–1600 r/min
1. Throttle cable free play
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-15
6 3. To increase the throttle cable free
play, turn the adjusting nut in direc-
tion (a). To decrease the throttle
cable free play, turn the adjusting
nut in direction (b).
4. Tighten the locknut and then slide
the rubber cover to its original po-
sition.
EAU21401
Valve clearance The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU21641
Tires To maximize the performance, durabil-
ity, and safe operation of your motorcy-
cle, note the following points regarding
the specified tires.
Tire air pressure
The tire air pressure should be checked
and, if necessary, adjusted before each
ride.
WARNING
EWA10501
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.

The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).


The tire air pressure must be ad-
justed in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approved
for this model.
1. Locknut
2. Adjusting nut
U22BE1E0.book Page 15 Wednesday, September 16, 2009 1:46 PM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-24
6
EAU23101
Checking and lubricating the
cables The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubricat-
ed if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING! Damage to the outer
sheath may interfere with proper ca-
ble operation and will cause the in-
ner cable to rust. Replace a
damaged cable as soon as possible
to prevent unsafe conditions.
[EWA10721]EAU23112
Checking and lubricating the
throttle grip and cable The operation of the throttle grip should
be checked before each ride. In addi-
tion, the cable should be lubricated by a
Yamaha dealer at the intervals speci-
fied in the periodic maintenance chart.
EAU23142
Checking and lubricating the
brake and clutch levers Brake lever
Clutch lever
The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be lu-
bricated if necessary.
Recommended lubricant:
Engine oil
U22BE1E0.book Page 24 Wednesday, September 16, 2009 1:46 PM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-27
6
EAU23283
Checking the steering Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the pe-
riodic maintenance and lubrication
chart.
1. Place a stand under the engine to
raise the front wheel off the
ground. (See page 6-32 for more
information.) WARNING! To
avoid injury, securely support
the vehicle so there is no danger
of it falling over.
[EWA10751]
2. Hold the lower ends of the front
fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steering.
EAU23291
Checking the wheel bearings The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer check
the wheel bearings.
EAU23324
Battery A poorly maintained battery will corrode
and discharge quickly. The electrolyte
level, battery lead connections and
breather hose routing should be
checked before each ride and at the in-
tervals specified in the periodic mainte-
nance and lubrication chart.
WARNING
EWA10770


Electrolyte is poisonous and
dangerous since it contains sul-
furic acid, which causes severe
burns. Avoid any contact with
skin, eyes or clothing and al-
ways shield your eyes when
working near batteries. In case
of contact, administer the fol-
lowing FIRST AID.
EXTERNAL: Flush with plenty
of water.
INTERNAL: Drink large quan-
tities of water or milk and im-
mediately call a physician.
EYES: Flush with water for 15
minutes and seek prompt
medical attention.
U22BE1E0.book Page 27 Wednesday, September 16, 2009 1:46 PM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-32
6
EAUM2620
Replacing the license plate
light bulb 1. Remove panel B. (See page 6-7.)
2. Remove the socket (together with
the bulb) by pulling it out.
3. Remove the burnt-out bulb by pull-
ing it out.
4. Insert a new bulb into the socket.
5. Install the socket (together with the
bulb) by pushing it in.
6. Install the panel.
EAU45222
Replacing an auxiliary light
bulb If the auxiliary light bulb burns out, re-
place it as follows.
1. Remove the headlight unit. (See
page 6-30.)
2. Remove the auxiliary light socket
(together with the bulb) by pulling it
out.
3. Remove the burnt-out bulb by pull-
ing it out.
4. Insert a new bulb into the socket.
5. Install the auxiliary light socket (to-
gether with the bulb) by pushing it
in.
6. Install the headlight unit.
EAU24350
Supporting the motorcycle Since this model is not equipped with a
centerstand, follow these precautions
when removing the front and rear
wheel or performing other maintenance
requiring the motorcycle to stand up-
right. Check that the motorcycle is in a
stable and level position before starting
any maintenance. A strong wooden
box can be placed under the engine for
added stability.
To service the front wheel
1. Stabilize the rear of the motorcycle
by using a motorcycle stand or, if
an additional motorcycle stand is
not available, by placing a jack un-
der the frame in front of the rear
wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
To service the rear wheel
Raise the rear wheel off the ground by
using a motorcycle stand or, if a motor-
cycle stand is not available, by placing
1. License plate light bulb
1. Auxiliary light bulb
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-37
6
EAUM2441
Troubleshooting charts Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wet
Dry
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.The engine does not start.
Check the battery.
Operate the electric starter.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.The battery is good.
Check the electrolyte and battery
lead connections, and charge the
battery if necessary.The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the compression.
U22BE1E0.book Page 37 Wednesday, September 16, 2009 1:46 PM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-38
6Engine overheating
WARNING
EWA10400


Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.


After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the hissing
sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended coolant
as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
U22BE1E0.book Page 38 Wednesday, September 16, 2009 1:46 PM

INDEX
AAir filter element and check hose,
replacing and cleaning ....................... 6-13
Auxiliary light bulb, replacing ................ 6-32BBattery .................................................. 6-27
Brake and clutch levers, checking and
lubricating ........................................... 6-24
Brake fluid, changing ............................ 6-21
Brake fluid level, checking .................... 6-20
Brake lever ............................................. 3-6
Brake pedal ............................................ 3-7
Brake pedal, checking and
lubricating ........................................... 6-25
Brake pedal free play, adjusting ........... 6-19CCables, checking and lubricating .......... 6-24
Care ........................................................ 7-1
Catalytic converters ................................ 3-9
Clutch lever............................................. 3-6
Clutch lever free play, adjusting ........... 6-18
Coolant ................................................. 6-12
Coolant temperature warning light.......... 3-2DDimmer switch ........................................ 3-5
Drive chain, cleaning and lubricating .... 6-23
Drive chain slack .................................. 6-22EEngine break-in ...................................... 5-3
Engine idling speed .............................. 6-14
Engine oil and oil filter element............... 6-9
Engine stop switch.................................. 3-5
Engine trouble warning light ................... 3-3
FFront and rear brake pads, checking .... 6-20
Front brake lever free play, checking .... 6-19
Front fork, checking...............................6-26
Fuel ......................................................... 3-8
Fuel consumption, tips for reducing ........ 5-3
Fuel tank cap........................................... 3-7
Fuses, replacing .................................... 6-29HHandlebar switches ................................. 3-5
Headlight bulb, replacing....................... 6-30
High beam indicator light......................... 3-2
Horn switch ............................................. 3-5IIdentification numbers ............................. 9-1
Ignition circuit cut-off system ................. 3-12
Indicator and warning lights .................... 3-2LLicense plate light bulb, replacing ......... 6-32MMain switch/steering lock ........................ 3-1
Maintenance and lubrication, periodic..... 6-3
Maintenance, emission control system ... 6-2
Model label .............................................. 9-1
Multi-function display...............................3-3NNeutral indicator light .............................. 3-2PPanels, removing and installing .............. 6-7
Parking ....................................................5-4
Part locations .......................................... 2-1
Pass switch ............................................. 3-5SSafety information ...................................1-1Seat ...................................................... 3-10
Shifting .................................................... 5-2
Shift pedal ............................................... 3-6
Shock absorber assembly, adjusting .... 3-10
Sidestand .............................................. 3-11
Sidestand, checking and lubricating ..... 6-25
Spark plug, checking .............................. 6-8
Specifications.......................................... 8-1
Starting the engine.................................. 5-1
Start switch ............................................. 3-5
Steering, checking ................................ 6-27
Storage ................................................... 7-3
Supporting the motorcycle .................... 6-32
Swingarm pivots, lubricating ................. 6-26
TTail/brake light bulb, replacing .............. 6-31
Throttle cable free play, adjusting ......... 6-14
Throttle grip and cable, checking and
lubricating ........................................... 6-24
Tires ...................................................... 6-15
Tool kit .................................................... 6-1
Troubleshooting .................................... 6-36
Troubleshooting charts ......................... 6-37
Turn signal indicator light ........................ 3-2
Turn signal light bulb, replacing ............ 6-31
Turn signal switch ................................... 3-5VValve clearance .................................... 6-15
Vehicle identification number .................. 9-1WWheel bearings, checking..................... 6-27
Wheel (front) ......................................... 6-33
Wheel (rear) .......................................... 6-34
Wheels .................................................. 6-17
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