2010 YAMAHA YBR125 check engine

PERIODIC MAINTENANCE AND ADJUSTMENT
6-12
610. Install the plug into the check
hose, and then install the clamp.
11. Install the panel.
EAU44734
Checking the engine idling
speed Check the engine idling speed and, if
necessary, have it corrected by a
Yamaha dealer.
EAU21383
Checking the throttle cable
free play The throttle cable free play should mea-
sure 3.0–7.0 mm (0.12–0.28 in) at the
inner edge of the throttle grip. Periodi-
cally check the throttle cable free play
and, if necessary, have a Yamaha deal-
er adjust it.
1. Clamp
2. Air filter check hose plug
Engine idling speed:
1300–1500 r/min
1. Throttle cable free play
1
U51DE0E0.book Page 12 Monday, November 2, 2009 10:34 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-13
6
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.
EAU21562
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.
WARNING
EWA10511
Never overload your vehicle. Opera-
tion of an overloaded vehicle could
cause an accident.
Tire air pressure (measured on cold
tires):
0–90 kg (0–198 lb):
Fr o nt :
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
200 kPa (2.00 kgf/cm², 29 psi)
90–153 kg (198–337 lb):
Fr o nt :
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
280 kPa (2.80 kgf/cm², 41 psi)
Maximum load*:
153 kg (337 lb)
* Total weight of rider, passenger, car-
go and accessories
U51DE0E0.book Page 13 Monday, November 2, 2009 10:34 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-22
6
EAU23025
Cleaning and lubricating the
drive chain The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.NOTICE
ECA10583
The drive chain must be lubricated
after washing the motorcycle, riding
in the rain or riding in wet areas.1. Clean the drive chain with kero-
sene and a small soft brush.
NOTICE: To prevent damaging
the O-rings, do not clean the
drive chain with steam cleaners,
high-pressure washers or inap-
propriate solvents.
[ECA11121]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant. NOTICE: Do not use
engine oil or any other lubri-
cants for the drive chain, as theymay contain substances that
could damage the O-rings.
[ECA11111]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]
Recommended lubricant:
Engine oil
U51DE0E0.book Page 22 Monday, November 2, 2009 10:34 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-36
6
EAU45731
Troubleshooting chart
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter
or the kickstarter.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
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.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Operate the electric starter
or the kickstarter.
U51DE0E0.book Page 36 Monday, November 2, 2009 10:34 AM

MOTORCYCLE CARE AND STORAGE
7-4
73. Perform the following steps to pro-
tect the cylinder, piston rings, etc.
from corrosion.
a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine oil
into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap. WARNING! To
prevent damage or injury
from sparking, make sure to
ground the spark plug elec-
trodes while turning the en-
gine over.
[EWA10951]
4. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.5. Check and, if necessary, correct
the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
6. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
7. Remove the battery and fully
charge it. Store it in a cool, dry
place and charge it once a month.
Do not store the battery in an ex-
cessively cold or warm place [less
than 0 °C (30 °F) or more than 30
°C (90 °F)]. For more information
on storing the battery, see page
6-26.
TIPMake any necessary repairs before
storing the motorcycle.
U51DE0E0.book Page 4 Monday, November 2, 2009 10:34 AM

INDEX
AAir filter element, cleaning .................... 6-10
Auxiliary light bulb, replacing ................ 6-31BBattery .................................................. 6-26
Brake and clutch levers, checking and
lubricating ........................................... 6-23
Brake fluid, changing ............................ 6-20
Brake fluid level, checking .................... 6-19
Brake lever ............................................. 3-5
Brake light switches .............................. 6-17
Brake pads and shoes, checking.......... 6-18
Brake pedal ............................................ 3-6
Brake pedal, checking and
lubricating ........................................... 6-24
Brake pedal free play, adjusting ........... 6-16CCables, checking and lubricating .......... 6-22
Care ........................................................ 7-1
Carrier................................................... 3-10
Catalytic converters ................................ 3-8
Centerstand and sidestand, checking
and lubricating .................................... 6-24
Clutch lever............................................. 3-5
Clutch lever free play, adjusting ........... 6-15DDimmer switch ........................................ 3-4
Drive chain, cleaning and lubricating .... 6-22
Drive chain slack .................................. 6-20EEngine break-in ...................................... 5-3
Engine idling speed, checking .............. 6-12
Engine oil ................................................ 6-9
Engine trouble warning light ................... 3-2
FFront brake lever free play, checking .... 6-16
Front fork, checking...............................6-25
Fuel ......................................................... 3-7
Fuel consumption, tips for reducing ........ 5-3
Fuel gauge .............................................. 3-4
Fuel tank cap........................................... 3-6
Fuse, replacing...................................... 6-28HHandlebar switches ................................. 3-4
Headlight bulb, replacing....................... 6-29
High beam indicator light......................... 3-2
Horn switch ............................................. 3-4IIdentification numbers ............................. 9-1
Ignition circuit cut-off system ................. 3-11
Indicator and warning lights .................... 3-2KKickstarter ............................................... 3-9MMain switch/steering lock ........................ 3-1
Maintenance and lubrication, periodic..... 6-3
Maintenance, emission control system ... 6-2
Matte color, caution .................................7-1
Model label .............................................. 9-1NNeutral indicator light .............................. 3-2PPanels, removing and installing .............. 6-6
Parking ....................................................5-4
Part locations .......................................... 2-1SSafety information ...................................1-1
Self-diagnosis device .............................. 3-3Shifting .................................................... 5-2
Shift pedal ............................................... 3-5
Shift pedal, checking............................. 6-17
Shock absorber assemblies, adjusting ... 3-9
Sidestand .............................................. 3-10
Spark plug, checking .............................. 6-7
Specifications.......................................... 8-1
Speedometer unit ................................... 3-3
Starting the engine.................................. 5-1
Start switch ............................................. 3-4
Steering, checking ................................ 6-26
Storage ................................................... 7-3
Swingarm pivots, lubricating ................. 6-25
TTachometer............................................. 3-3
Tail/brake light bulb, replacing .............. 6-30
Throttle cable free play, checking ......... 6-12
Throttle grip and cable, checking and
lubricating ........................................... 6-23
Tires ...................................................... 6-13
Tool kit .................................................... 6-1
Troubleshooting .................................... 6-35
Troubleshooting chart ........................... 6-36
Turn signal indicator lights ...................... 3-2
Turn signal light bulb, replacing ............ 6-31
Turn signal switch ................................... 3-4VValve clearance .................................... 6-13
Vehicle identification number .................. 9-1WWheel bearings, checking..................... 6-26
Wheel (front) ......................................... 6-32
Wheel (rear) .......................................... 6-33
Wheels .................................................. 6-15
U51DE0E0.book Page 1 Monday, November 2, 2009 10:34 AM