2008 YAMAHA YBR125 check engine

TABLE OF CONTENTSSAFETY INFORMATION ..................1-1
DESCRIPTION ..................................2-1
Left view ..........................................2-1
Right view ........................................2-2
Controls and instruments.................2-3
INSTRUMENT AND CONTROL
FUNCTIONS.......................................3-1
Main switch/steering lock ................3-1
Indicator and warning lights ............3-2
Speedometer unit ...........................3-2
Tachometer ....................................3-3
Self-diagnosis device ......................3-3
Fuel gauge ......................................3-3
Handlebar switches ........................3-4
Clutch lever .....................................3-5
Shift pedal .......................................3-5
Brake lever .....................................3-5
Brake pedal ....................................3-6
Fuel tank cap ..................................3-6
Fuel .................................................3-7
Catalytic converters ........................3-8
Kickstarter .......................................3-8
Adjusting the shock absorber
assemblies ..................................3-8
Carrier .............................................3-9
Sidestand ........................................3-9
Ignition circuit cut-off system ........3-10PRE-OPERATION CHECKS............. 4-1
Pre-operation check list .................. 4-2
OPERATION AND IMPORTANT
RIDING POINTS................................. 5-1
Starting the engine ......................... 5-1
Shifting ........................................... 5-2
Tips for reducing fuel
consumption ............................... 5-3
Engine break-in .............................. 5-3
Parking ........................................... 5-4
PERIODIC MAINTENANCE AND
MINOR REPAIR................................. 6-1
Owner’s tool kit ............................... 6-1
Periodic maintenance and
lubrication chart .......................... 6-2
Removing and installing panels ..... 6-6
Checking the spark plug ................. 6-7
Engine oil ....................................... 6-9
Cleaning the air filter element ...... 6-10
Checking the engine idling
speed ........................................ 6-12
Adjusting the throttle cable free
play ........................................... 6-12
Valve clearance ............................ 6-13
Tires ............................................. 6-13
Cast wheels .................................. 6-15
Adjusting the clutch lever free
play ........................................... 6-16Checking the front brake lever free
play ........................................... 6-17
Adjusting the brake pedal free
play ........................................... 6-17
Checking the shift pedal .............. 6-18
Adjusting the rear brake light
switch ....................................... 6-18
Checking the front brake pads and
rear brake shoes ...................... 6-19
Checking the front brake fluid
level .......................................... 6-19
Changing the brake fluid .............. 6-20
Drive chain slack .......................... 6-21
Cleaning and lubricating the drive
chain ......................................... 6-22
Checking and lubricating
the cables ................................. 6-23
Checking and lubricating
the throttle grip and cable ......... 6-23
Checking and lubricating
the brake and clutch levers ...... 6-23
Checking and lubricating
the brake pedal ......................... 6-24
Checking and lubricating the
centerstand and sidestand ....... 6-24
Lubricating the swingarm
pivots ........................................ 6-25
Checking the front fork ................. 6-25
Checking the steering .................. 6-26
Checking the wheel bearings ....... 6-26
Battery ......................................... 6-27U27SE0E0.book Page 1 Friday, February 22, 2008 8:54 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-2
3
EAU11003
Indicator and warning lights
EAU11020
Turn signal indicator light“”
This indicator light flashes when the
turn signal switch is pushed to the left or
right.
EAU11060
Neutral indicator light“”
This indicator light comes on when the
transmission is in the neutral position.
EAU11080
High beam indicator light“”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAU45740
Engine trouble warning light“”
This warning light comes on or flashes
when an electrical circuit monitoring the
engine is defective. When this occurs,
have a Yamaha dealer check the self-
diagnosis system. (See page 3-3 for an
explanation of the self-diagnosis de-
vice.)
The electrical circuit of the warning light
can be checked by turning the key to
“ON”. If the warning light does not come
on for a few seconds, then go off, have
a Yamaha dealer check the electrical
circuit.
EAU11630
Speedometer unit The speedometer unit is equipped with
a speedometer, an odometer and a
tripmeter. The speedometer shows
riding speed. The odometer shows the
total distance traveled. The tripmeter
shows the distance traveled since it
was last set to zero with the reset knob.
The tripmeter can be used to estimate
the distance that can be traveled with a
full tank of fuel. This information will en-
able you to plan future fuel stops.
1. Turn signal indicator light“”
2. Neutral indicator light“”
3. High beam indicator light“”
4. Engine trouble warning light“”
1
2
3
4
1. Speedometer
2. Odometer
3. Tripmeter
4. Tripmeter reset knob
14
32
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INSTRUMENT AND CONTROL FUNCTIONS
3-3
3
EAU11851
Tachometer The electric tachometer allows the rider
to monitor the engine speed and keep it
within the ideal power range.CAUTION:
ECA10031
Do not operate the engine in the ta-
chometer red zone.Red zone: 10000 r/min and above
EAU12090
Self-diagnosis device This model is equipped with a self-diag-
nosis device for various electrical cir-
cuits.
If any of those circuits are defective, the
engine trouble warning light will come
on or flash. If this occurs, have a
Yamaha dealer check the vehicle.CAUTION:
ECA11170
To prevent engine damage, be sure
to consult a Yamaha dealer as soonas possible if this occurs.
EAU37052
Fuel gauge The fuel gauge indicates the amount of
fuel in the fuel tank. The needle moves
towards “E” (Empty) as the fuel level
decreases. When the needle reaches
the red zone, approximately 3.0 L (0.79
US gal, 0.66 Imp.gal) remain in the fuel
tank. If this occurs, refuel as soon as
possible.NOTE:The main switch must be turned to
“ON” for the fuel gauge to display anaccurate fuel level reading.
1. Tachometer
2. Tachometer red zone
1
2
1. Fuel gauge
2. Red zone
12
U27SE0E0.book Page 3 Friday, February 22, 2008 8:54 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-10
3below and have a Yamaha dealer re-
pair it if it does not function proper-
ly.
EAU43161
Ignition circuit cut-off system The ignition circuit cut-off system (com-
prising the sidestand switch, clutch
switch and neutral switch) has the fol-
lowing functions.

It prevents starting when the trans-
mission is in gear and the side-
stand is up, but the clutch lever is
not pulled.


It prevents starting when the trans-
mission is in gear and the clutch le-
ver is pulled, but the sidestand is
still down.


It cuts the running engine when the
transmission is in gear and the sid-
estand is moved down.
Periodically check the operation of the
ignition circuit cut-off system according
to the following procedure.WARNING
EWA10260


The vehicle must be placed on
the centerstand during this in-
spection.


If a malfunction is noted, have a
Yamaha dealer check the sys-tem before riding.
U27SE0E0.book Page 10 Friday, February 22, 2008 8:54 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-11
3
With the engine turned off:
1. Move the sidestand down.
2. Turn the key on.
3. Shift the transmission into the neutral position.
4. Push the start switch or push the kickstarter lever down.
Does the engine start?
With the engine still running:
5. Move the sidestand up.
6. Keep the clutch lever pulled.
7. Shift the transmission into gear.
8. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
9. Move the sidestand up.
10. Keep the clutch lever pulled.
11. Push the start switch or push the kickstarter lever down.
Does the engine start?
The system is OK. The motorcycle can be ridden.The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The sidestand switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The clutch switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
YES NO YES NO YES NO
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PRE-OPERATION CHECKS
4-2
4
EAU15605
Pre-operation check list
ITEM CHECKS PAGE
FuelCheck fuel level in fuel tank.
Refuel if necessary.
Check fuel line for leakage.3-7
Engine oilCheck oil level in engine.
If necessary, add recommended oil to specified level.
Check vehicle for oil leakage.6-9
Front brakeCheck operation.
If soft or spongy, have Yamaha dealer bleed hydraulic system.
Check brake pads for wear.
Replace if necessary.
Check fluid level in reservoir.
If necessary, add recommended brake fluid to specified level.
Check hydraulic system for leakage.6-19, 6-19
Rear brakeCheck operation.
Check pedal free play.
Adjust if necessary.6-17, 6-19
ClutchCheck operation.
Lubricate cable if necessary.
Check lever free play.
Adjust if necessary.6-16
Throttle gripMake sure that operation is smooth.
Check cable free play.
If necessary, have Yamaha dealer adjust cable free play and lubricate cable and
grip housing.6-12, 6-23
Control cablesMake sure that operation is smooth.
Lubricate if necessary.6-23
Drive chainCheck chain slack.
Adjust if necessary.
Check chain condition.
Lubricate if necessary.6-21, 6-22
U27SE0E0.book Page 2 Friday, February 22, 2008 8:54 AM

OPERATION AND IMPORTANT RIDING POINTS
5-1
5
EAU15950
WARNING
EWA10270


Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer re-
garding any control or function
that you do not thoroughly un-
derstand.


Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.


Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible lossof control.
EAU45310
NOTE:This model is equipped with a lean an-
gle sensor to stop the engine in case of
a turnover. To start the engine after a
turnover, be sure to turn the main
switch to “OFF” and then to “ON”. Fail-
ing to do so will prevent the engine from
starting even though the engine willcrank when pushing the start switch.
EAU43181
Starting the engine In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:

The transmission is in the neutral
position.


The transmission is in gear with
the clutch lever pulled and the sid-
estand up.WARNING
EWA10290


Before starting the engine,
check the function of the igni-
tion circuit cut-off system ac-
cording to the procedure
described on page 3-10.


Never ride with the sidestanddown.
1. Turn the key to “ON”.
2. Shift the transmission into the neu-
tral position.
NOTE:When the transmission is in the neutral
position, the neutral indicator light
should be on, otherwise have a
Yamaha dealer check the electrical cir-cuit.
U27SE0E0.book Page 1 Friday, February 22, 2008 8:54 AM

OPERATION AND IMPORTANT RIDING POINTS
5-2
53. Start the engine by pushing the
start switch or by pushing the kick-
starter lever down.
NOTE:If the engine fails to start when using
the start switch, release it, wait a few
seconds, and then try again. Each
starting attempt should be as short as
possible to preserve the battery. Do not
crank the engine more than 10 seconds
on any one attempt. If the engine does
not start with the starter motor, try usingthe kickstarter.CAUTION:
ECA11370
The engine trouble warning light
should come on when the key is
turned to “ON”, and then go off after
a few seconds. If the engine trouble
warning light comes on or flashes
after starting, immediately stop the
engine, and have a Yamaha dealercheck the self-diagnosis system.
CAUTION:
ECA11040
For maximum engine life, never ac-
celerate hard when the engine iscold!
EAU16671
Shifting Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing hills,
etc.
The gear positions are shown in the il-
lustration.NOTE:To shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of itstravel, and then slightly raise it.1. Shift pedal
2. Neutral position
U27SE0E0.book Page 2 Friday, February 22, 2008 8:54 AM