check engine YAMAHA YBR125 2006 User Guide

PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
6
EAU21320
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.NOTE:
The engine is warm when it quickly re-sponds to the throttle.
Check the engine idling speed and, if
necessary, adjust it to specification by
turning the throttle stop screw. To in-
crease the engine idling speed, turn the
screw in direction (a). To decrease the
engine idling speed, turn the screw in
direction (b).
NOTE:
If the specified idling speed cannot be
obtained as described above, have aYamaha dealer make the adjustment.
EAU21370
Adjusting 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
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.NOTE:The engine idling speed must be cor-
rectly adjusted before checking and ad-justing the throttle cable free play.
1. Loosen the locknut.
1. Throttle stop screw
Engine idling speed:
1300–1500 r/min
1. Throttle cable free play
2. Locknut
3. Adjusting nut
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-14
62. 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).
3. Tighten the locknut.
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.
EAU21540
Tires To maximize the performance, durabil-
ity, and safe operation of your motor-
cycle, 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
EWA10500


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 approvedfor this model.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-23
6
CAUTION:
ECA10570
Improper drive chain slack will over-
load the engine as well as other vital
parts of the motorcycle and can lead
to chain slippage or breakage. To
prevent this from occurring, keep
the drive chain slack within thespecified limits.
4. Tighten both locknuts, and then
tighten the axle nut and brake
torque rod nut to their specified
torques.
5. Adjust the brake pedal free play.
(See page 6-18.)
WARNING
EWA10660
After adjusting the brake pedal free
play, check the operation of thebrake light.
EAU23022
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.CAUTION:
ECA10581
The drive chain must be lubricated
after washing the motorcycle andriding in the rain.
1. Clean the drive chain with kero-
sene and a small soft brush.CAUTION:
ECA11120
To prevent damaging the O-rings, do
not clean the drive chain with steam
cleaners, high-pressure washers orinappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant.
CAUTION:
ECA11110
Do not use engine oil or any other lu-
bricants for the drive chain, as they
may contain substances that coulddamage the O-rings.
Tightening torques:
Axle nut:
91 Nm (9.1 m·kgf, 66 ft·lbf)
Brake torque rod nut:
19 Nm (1.9 m·kgf, 13 ft·lbf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-24
6
EAU23100
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
EWA10720
Damage to the outer sheath may in-
terfere with proper cable operation
and will cause the inner cable to
rust. Replace a damaged cable as
soon as possible to prevent unsafeconditions.
EAU23111
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 at
the intervals specified in the periodic
maintenance chart.
EAU23131
Checking and lubricating the
brake and shift pedals The operation of the brake and shift
pedals should be checked before each
ride, and the pedal pivots should be lu-
bricated if necessary.
Recommended lubricant:
Engine oil
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-27
6
CAUTION:
ECA10590
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-pair it.
EAU23280
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.
WARNING
EWA10750
Securely support the vehicle so thatthere is no danger of it falling over.
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.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-38
6
EAU25962
Troubleshooting chart
WARNING
EWA10840
Keep away open flames and do not smoke while checking or working on the fuel system.
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.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. Have a
Yamaha dealer check the vehicle.The engine does not start.
Check the battery.Open the throttle halfway and
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 fluid, recharge,
check connections.
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MOTORCYCLE CARE AND STORAGE
7-4
7
WARNING
EWA10950
To prevent damage or injury from
sparking, make sure to ground the
spark plug electrodes while turningthe engine over.
6. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.
7. 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.
8. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
9. 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
6-28.
NOTE:Make any necessary repairs beforestoring the motorcycle.
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INDEXAAir filter element, cleaning..................... 6-11
Auxiliary light bulb, replacing ................ 6-33BBattery................................................... 6-28
Brake and clutch levers, checking and
lubricating ........................................... 6-25
Brake and shift pedals, checking and
lubricating ........................................... 6-24
Brake fluid, changing ............................ 6-21
Brake fluid level, checking .................... 6-20
Brake lever .............................................. 3-5
Brake pads and shoes, checking .......... 6-20
Brake pedal ............................................. 3-5
Brake pedal free play, adjusting............ 6-18CCables, checking and lubricating .......... 6-24
Carburetor, adjusting ............................ 6-12
Care ........................................................ 7-1
Carrier ................................................... 3-10
Catalytic converter .................................. 3-7
Centerstand, checking and
lubricating ........................................... 6-26
Clutch lever ............................................. 3-4
Clutch lever free play, adjusting ............ 6-17
Cowling and panels, removing and
installing................................................ 6-5DDimmer switch ........................................ 3-4
Drive chain, cleaning and lubricating .... 6-23
Drive chain slack ................................... 6-22EEngine break-in ....................................... 5-3
Engine idling speed............................... 6-13Engine oil ................................................ 6-9
Engine, starting a warm .......................... 5-2
FFront brake lever free play,
checking ............................................. 6-18
Front fork, checking .............................. 6-26
Fuel......................................................... 3-6
Fuel cock ................................................ 3-7
Fuel consumption, tips for reducing........ 5-3
Fuel gauge.............................................. 3-3
Fuel tank cap .......................................... 3-5
Fuse, replacing ..................................... 6-30HHandlebar switches ................................ 3-3
Headlight bulb, replacing ...................... 6-31
High beam indicator light ........................ 3-2
Horn switch ............................................. 3-4IIdentification numbers ............................ 9-1
Indicator lights ........................................ 3-2KKey identification number ....................... 9-1
Kickstarter............................................... 3-9LLuggage strap holders .......................... 3-10MMain switch/steering lock........................ 3-1
Model label ............................................. 9-2NNeutral indicator light .............................. 3-2PParking ................................................... 5-4
Part locations .......................................... 2-1Periodic maintenance and lubrication
chart ...................................................... 6-2
Pre-operation check list........................... 4-2
RRear brake light switch, adjusting ......... 6-19SSafety information ................................... 1-1
Shifting .................................................... 5-2
Shift pedal ............................................... 3-4
Shock absorber assemblies, adjusting.... 3-9
Spark plug, checking ............................... 6-8
Specifications .......................................... 8-1
Speedometer unit .................................... 3-2
Starter (choke) lever................................ 3-8
Starting a cold engine ............................. 5-1
Starting circuit cut-off system ................ 3-10
Start switch.............................................. 3-4
Steering, checking................................. 6-27
Storage.................................................... 7-3
Swingarm pivots, lubricating ................. 6-26TTachometer ............................................. 3-3
Tail/brake light bulb, replacing .............. 6-32
Throttle cable free play, adjusting ......... 6-13
Throttle grip and cable, checking and
lubricating ........................................... 6-24
Tires ...................................................... 6-14
Tool kit..................................................... 6-1
Troubleshooting .................................... 6-37
Troubleshooting chart ........................... 6-38
Turn signal indicator lights ...................... 3-2
Turn signal light bulb, replacing ............ 6-33
Turn signal switch ................................... 3-4
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