YAMAHA YBR125 2007 Service Manual

WARNING1. It is dangerous to ride with a
worn-out tyre. When a tyre
tread begins to show lines,
have a YAMAHA dealer replace
the tyre immediately.
WheelsTo ensure maximum performance,
long service, and safe operation,
note the following:
1. Always inspect the wheels before
a ride. Check for cracks, bends or
warpage of the wheel. Be sure the
spokes are tight and undamaged.
If any abnormal condition exists in
a wheel, consult a YAMAHA
dealer. Do not attempt even small
repairs to the wheel. If a wheel is
deformed or cracked, it must be
replaced.
2. Tyres and wheels should be
balanced whenever either one is
changed or replaced. Failure to
have a wheel balanced can result
in poor performance, adverse
handling characteristics, and
shortened tyre life.3. Ride at moderate speeds after
changing a tyre since the tyre
surface must first be broken in for
it to develop its optimal
characteristics.PERIODIC MAINTENANCE AND MINOR REPAIR
6-15

1. Locknut
2. Adjusting nut
3. Free playClutch lever free play
adjustmentThe clutch lever free play should be
adjusted to 10 ~ 15 mm. If the free
play is incorrect, adjust as follows.
1 . Loosen the locknut.
2. Turn the adjusting nut in direction
to increase free play or in
direction to decrease free
play.
3. Tighten the locknut.è
çIf proper adjustment cannot be
obtained or the clutch does not work
correctly, ask a dealer to
inspect the internal clutch
mechanism.YAMAHA
1. Adjusting nut
2. Free playFront brake adjustmentThe front brake lever free play should
be adjusted to 10 ~ 15 mm.
1. Turn the adjusting nut in direction
to increase free play and
direction to decrease free play. ç
è
When it is impossible to make the
proper adjustment, ask a YAMAHA
dealer.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-16
NOTE :
WARNING

1. Adjusting NutRear brake adjustmentThe rear brake pedal free play
should be adjusted to 20 ~ 30 mm at
the brake pedal end. Turn the
adjusting nut in direction to
increase free play and in direction
to decrease free play.ç
è
a. Freeplay When it is impossible to make
the proper adjustment, ask a
YAMAHA dealer.
Check the operation of the
brake light after adjusting the
rear brake.
1. Brake light switch
2. Adjusting nutBrake light switch adjustmentThe rear brake light switch is acti-
vated by the brake pedal and is
properly adjusted when the brake
light comes on just before braking
takes effect. To adjust the rear
brake light switch, hold the switch
body so it does not rotate while
turning the adjusting nut.
Turn the adjusting nut in direction ç
to make the brake light come on
earlier.
Turn the adjusting nut in direction è
to make the brake light come on
later.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
WARNING
1
2
çè

1. Wear limit line
2. Wear indicatorChecking the brake shoesA wear indicator is provided on each
brake. This indicator allows
inspection of shoe wear without
disassembling the brake. Apply the
brake and inspect the position of the
indicator. If the indicator reaches to
the wear limit line, ask a YAMAHA
dealer to replace the shoes.
1. Wear limit line
2. Wear indicator1. Free play
Drive chain slack checkSpin the wheel several times and
find the tightest position of the
chain. Check and/or adjust the
chain slack while it's in this tightest
position.
Inspect the drive chain when the
Motorcycle is on the centerstand.
Check the slack at the position
shown in the illustration. Normal
slack is approximately 20 ~ 30 mm.
If the slack exceeds 30 mm, adjust.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-18
NOTE :

1. Chain jointIf the chain is disassembled, be sure
the chain lock is placed in the
correct direction when installing.
1. Adjusting nut
2. Cotter pin
3. Axle nutDrive chain slack adjust-
ment1. Loosen the rear brake pedal
free play adjusting nut.
2. Remove the cotter pin from
the axle nut.
3. Loosen the axle nut.
1. Locknut
2. Adjusting hex screw4. Loosen the chain adjusting
locknuts on each chain puller. To
tighten the chain, turn the chain
adjusting hex screw in direction b
to loosen the chain, turn the chain
adjusting hex screw in direction a
and push the wheel forward. Turn
each chain adjusting hex screw
exactly the same amount to
maintain correct axle alignment.
There are marks on each chain
puller. Use these marks to align
the rear wheel.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-19

CAUTION :
5. After adjusting, be sure to tighten
each chain adjusting locknut.
Then tighten the axle nut to the
specified torque.Maintain chain slackness
within specified limits as per
specifications.
To maintain correct axle
alignment, Ensure the notch
on the adjuster is on the same
Mark on Left and Right Side.
Tightening torque:
Axle nut:
65 ft-lb (9.05 m-kg)
1. Cotter pin6. Insert a new cotter pin into the
axle nut and bend the end of the
cotter pin as shown. If the notch in
the axle nut and the cotter pin
hole do not match, tighten the nut
slightly to align them.
Always use a new cotter pin on
the axle nut.7 Adjust the free play in the
brake pedal.
Check the operation of the brake
light after adjusting the rear
brake.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-20
WARNING
WARNING

Drive chain lubricationThe chain consists of many parts
which work with each other. If the
chain is not maintained properly, it
will wear out quickly. Therefore, the
chain must be serviced regularly.
This service is especially necessary
when riding in dusty areas.
1. The drive chain should be
lubricated every 5,000 km.
2. To clean the chain thoroughly,
remove it from the Motorcycle,
dip it in solvent, and clean out as
much dirt as possible. Then, take
the chain out of the solvent to dry
it, and then dip the chain in oil of
20W40. Remove the chain and
hang it on a peg for a while till the
excess oil drips down completely.
Then using a clean cloth wipe the
chain.
Cable inspection and
lubricationDamage to the outer housing of
cables may lead to internal rusting
and interfere with the cable
movement. Replace damaged
cables as soon as possible to
prevent unsafe conditions.
Lubricate the cables with anti-
corrosive oil and cable ends. If a
cable does not operate smoothly,
ask a YAMAHA dealer to replace it.
Recommended lubricant:
20W40 Type SG
Throttle cable and grip
lubricationThe throttle twist grip assembly
should be greased at the time that
the cable is lubricated, since the
grip must be removed to get at the
end of the throttle cable. After
removing the screws, hold the end
of the cable up in the air and put in
several drops of lubricant. With the
throttle grip disassembled, coat the
metal surface of the grip assembly
with a suitable all purpose grease.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-21
WARNING

Brake and shift pedal
lubricationLubricate the pivoting parts.
Recommended lubricant:
20W40 Type SG
Brake and Clutch Lever
GreasingGrease the pivoting parts.
MULTIPURPOSE Recommended Grease :
Center and sidestand
lubricationLubricate the pivoting and mating
joints.
Check to see that the center and
sidestand move up and down
smoothly.
Recommended lubricant:
If the center and/or sidestand does
not move smoothly, consult
aYAMAHA dealer.20W40 Type SG
PERIODIC MAINTENANCE AND MINOR REPAIR
6-22
WARNING

CAUTION :
Front fork inspectionSecurely support the Motorcycle
so there is no danger of it falling
over.
1. Visual check
Check for scratches or damage
on the inner tube and traces of oil
leakage from the front fork.2. Operation check
Place the Motorcycle on a level
place.
a. Hold the Motorcycle in an
upright position and apply the
front brake.
b. Push down hard on the
handlebars several times and
check if the fork rebounds
smoothly.
If any damage or unsmooth
movement is found with the front
fork, consult a YAMAHA dealer.
Steering inspectionPeriodically inspect the condition of
the steering. Worn out or loose
steering bearings may be danger-
ous. Place a stand under the engine
to raise the front wheel off the
ground. Hold the lower end of the
front forks and try to move them
forward and backward. If any free
play can be felt, ask a YAMAHA
dealer to inspect and adjust the
steering. Inspection is easier if the
front wheel is removed.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-23
WARNING

Securely support the Motorcycle
so there is no danger of it falling
over.
Wheel bearingsIf there is play in the front or rear
wheel hub or if the wheel does not
turn smoothly, have a YAMAHA
dealer inspect the wheel bearings.
1. Maximum level mark
2. Minimum level markBattery1. Battery is located inside the
L.H. side panel (for removal &
installation of L.H. side panel
please refer page 6-5)
2. Open the lid.
3. Check the level of the battery
electrolyte and make sure that
the terminals are tight.
Top up with distilled water if the
electrolyte level is low.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-24
WARNING