lock YAMAHA YBR125 2008 User Guide

PERIODIC MAINTENANCE AND MINOR REPAIR
6-21
6
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22793
To check the drive chain slack
1. Place the motorcycle on the cen-
terstand.
2. Shift the transmission into the neu-
tral position.
3. Spin the rear wheel several times
to locate the tightest portion of the
drive chain.
4. Measure the drive chain slack as
shown.5. If the drive chain slack is incorrect,
adjust it as follows.
EAU37112
To adjust the drive chain slack
1. Loosen the brake pedal free play
adjusting nut, brake torque rod nut,
and axle nut.
2. Loosen the chain puller locknut at
each end of the swingarm.3. To tighten the drive chain, turn the
adjusting bolt at each end of the
swingarm in direction (a). To loos-
en the drive chain, turn the adjust-
ing bolt at each end of the
swingarm in direction (b), and then
push the rear wheel forward.
NOTE:Using the alignment marks on each
side of the swingarm, make sure that
both chain pullers are in the same posi-tion for proper wheel alignment.
1. Drive chain slack
Drive chain slack:
20.0–30.0 mm (0.79–1.18 in)
1. Drive chain slack adjusting bolt
2. Chain puller locknut
3. Axle nut
4. Brake torque rod nut
5. Brake pedal free play adjusting nut
4
5 12
3
1. Alignment marks
2. Chain puller locknut
3. Drive chain slack adjusting bolt
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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)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-29
6
CAUTION:
ECA10640
Do not use a fuse of a higher amper-
age rating than recommended to
avoid causing extensive damage to
the electrical system and possibly afire.
3. Turn the key to “ON” and turn on
the electrical circuits to check if the
devices operate.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
EAU43190
Replacing the headlight bulb This model is equipped with a quartz
bulb headlight. If the headlight bulb
burns out, replace it as follows.
1. Remove the headlight unit by re-
moving the screws.
2. Remove the headlight bulb socket
cover.3. Remove the headlight bulb socket
(together with the bulb) by turning
it counterclockwise.
4. Remove the defective bulb by
pushing it in and turning it counter-
clockwise.1. Screw
1. Headlight bulb socket cover
1. Headlight bulb socket
1
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-30
6
WARNING
EWA10790
Headlight bulbs get very hot. There-
fore, keep flammable products away
from a lit headlight bulb, and do not
touch the bulb until it has cooleddown.
5. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.CAUTION:
ECA10660
Do not touch the glass part of the
headlight bulb to keep it free from
oil, otherwise the transparency of
the glass, the luminosity of the bulb,
and the bulb life will be adversely af-fected. Thoroughly clean off any dirt
and fingerprints on the headlight
bulb using a cloth moistened with al-
cohol or thinner.
6. Install the socket (together with the
bulb) by turning it clockwise.
7. Install the headlight bulb socket
cover.
8. Install the headlight unit by install-
ing the screws.
9. Have a Yamaha dealer adjust the
headlight beam if necessary.
EAU24131
Replacing the tail/brake light
bulb 1. Remove the tail/brake light lens by
removing the screws.
2. Remove the defective bulb by
pushing it in and turning it counter-
clockwise.
1. Headlight bulb
1. Do not touch the glass part of the bulb.
1. Screw
1
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-31
6 3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screws.
CAUTION:
ECA10680
Do not overtighten the screws, oth-erwise the lens may break.
EAU24202
Replacing a turn signal light
bulb 1. Remove the turn signal light lens
by removing the screw.
2. Remove the defective bulb by
pushing it in and turning it counter-
clockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screw.CAUTION:
ECA11190
Do not overtighten the screw, other-wise the lens may break.
EAU37270
Replacing the auxiliary light
bulb If the auxiliary light bulb burns out, re-
place it as follows.
1. Remove the headlight unit by re-
moving the screws.
2. Remove the socket (together with
the bulb) by pulling it out.
1. Tail/brake light bulb
1
1. Screw
1
1. Screw
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-35
6 5. Loosen the chain puller locknut
and the drive chain slack adjusting
bolt on both ends of the swingarm.6. Remove the axle nut, and then pull
the wheel axle out.
7. Push the wheel forward, and then
remove the drive chain from the
rear sprocket.
NOTE:The drive chain does not need to be
disassembled in order to remove andinstall the wheel.
8. Remove the wheel.
EAU37192
To install the rear wheel
1. Install the wheel by inserting the
wheel axle from the left-hand side.
2. Install the drive chain onto the rear
sprocket.
3. Install the axle nut.
4. Install the brake rod onto the brake
camshaft lever, and then install the
brake pedal free play adjusting nut
onto the brake rod.
5. Connect the brake torque rod to
the brake shoe plate by installing
the bolt and nut.
6. Adjust the drive chain slack. (See
page 6-21.)7. Take the motorcycle off the center-
stand so that the rear wheel is on
the ground.
8. Tighten the brake torque rod nut
and axle nut to the specified
torques.
9. Insert a new cotter pin.
10. 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.
1. Brake pedal free play adjusting nut
2. Brake rod
3. Brake camshaft lever
1. Wheel axle
2. Chain puller locknut
3. Drive chain slack adjusting bolt1
23
Tightening torques:
Brake torque rod nut:
19 Nm (1.9 m·kgf, 13 ft·lbf)
Axle nut:
80 Nm (8.0 m·kgf, 58 ft·lbf)
U27SE0E0.book Page 35 Friday, February 22, 2008 8:54 AM

INDEX
AAir filter element, cleaning .................... 6-10
Auxiliary light bulb, replacing ................ 6-31BBattery .................................................. 6-27
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 pads and shoes, checking.......... 6-19
Brake pedal ............................................ 3-6
Brake pedal, checking and
lubricating ........................................... 6-24
Brake pedal free play, adjusting ........... 6-17CCables, checking and lubricating .......... 6-23
Care ........................................................ 7-1
Carrier..................................................... 3-9
Catalytic converters ................................ 3-8
Centerstand and sidestand,
checking and lubricating ..................... 6-24
Clutch lever............................................. 3-5
Clutch lever free play, adjusting ........... 6-16DDimmer switch ........................................ 3-4
Drive chain, cleaning and lubricating .... 6-22
Drive chain slack .................................. 6-21EEngine 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 .... 6-17
Front fork, checking...............................6-25
Fuel ......................................................... 3-7
Fuel consumption, tips for reducing ........ 5-3
Fuel gauge .............................................. 3-3
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 ................. 3-10
Indicator and warning lights .................... 3-2KKey identification number ........................ 9-1
Kickstarter ............................................... 3-8MMain switch/steering lock ........................ 3-1
Matte color, caution .................................7-1
Model label .............................................. 9-2NNeutral indicator light .............................. 3-2PPanels, removing and installing .............. 6-6
Parking ....................................................5-4
Part locations .......................................... 2-1
Periodic maintenance and
lubrication chart.....................................6-2
Pre-operation check list........................... 4-2
RRear brake light switch, adjusting ......... 6-18SSafety information ................................... 1-1
Self-diagnosis device .............................. 3-3
Shifting .................................................... 5-2
Shift pedal ............................................... 3-5
Shift pedal, checking............................. 6-18
Shock absorber assemblies, adjusting ... 3-8
Sidestand ................................................ 3-9
Spark plug, checking .............................. 6-7
Specifications.......................................... 8-1
Speedometer unit ................................... 3-2
Starting the engine.................................. 5-1
Start switch ............................................. 3-4
Steering, checking ................................ 6-26
Storage ................................................... 7-3
Swingarm pivots, lubricating ................. 6-25TTachometer............................................. 3-3
Tail/brake light bulb, replacing .............. 6-30
Throttle cable free play, adjusting ......... 6-12
Throttle grip and cable,
checking and lubricating ..................... 6-23
Tires ...................................................... 6-13
Tool kit .................................................... 6-1
Troubleshooting .................................... 6-36
Troubleshooting chart ........................... 6-37
Turn signal indicator light ........................ 3-2
Turn signal light bulb, replacing ............ 6-31
Turn signal switch ................................... 3-4VValve clearance .................................... 6-13
Vehicle identification number .................. 9-1
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