2008 YAMAHA YBR125 check engine light

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

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

PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
NOTE:
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer checkthe vehicle.2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
To install the spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.2. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
NOTE:
If a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-fied torque as soon as possible.
4. Install the spark plug cap.
1. Spark plug wrench
Specified spark plug:
NGK/CR6HSA1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
U27SE0E0.book Page 8 Friday, February 22, 2008 8:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6
EAU37171
Engine oil The engine oil level should be checked
before each ride. In addition, the oil
must be changed at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
To check the engine oil level
1. Place the vehicle on the center-
stand.NOTE:Make sure that the vehicle is positioned
straight up when checking the oil level.
A slight tilt to the side can result in afalse reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.
NOTE:
The engine oil should be between theminimum and maximum level marks.4. If the engine oil is at or below the
minimum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the engine
to collect the used oil.
3. Remove the engine oil filler cap
and drain bolt to drain the oil from
the crankcase.1. Engine oil filler cap
1. Dipstick
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt
2. Oil pan
U27SE0E0.book Page 9 Friday, February 22, 2008 8:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-22
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 6-17.)
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:
80 Nm (8.0 m·kgf, 58 ft·lbf)
Brake torque rod nut:
19 Nm (1.9 m·kgf, 13 ft·lbf)
U27SE0E0.book Page 22 Friday, February 22, 2008 8:54 AM