wheel YAMAHA YBR125 2003 User Guide

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Drive chain slack check NOTE:
Spin the wheel several times and find the tightest position
of the chain. Check and/or adjust the chain slack while it is
in this tightest position.
To check the chain slack the motorcycle must be held
straight up with both wheels on the ground and without rider.
Check the slack at the position shown in the illustration.
Normal slack is approximately 20 ~ 30 mm ( 0.8 ~ 1.2
in). If the slack exceeds 30 mm ( 1.2 in), adjust.
a. 20 ~ 30 mm (0.8 ~ 1.2 in)
!


Drive chain slack check NOTE:
Spin the wheel several times and find the tightest position
of the chain. Check and/or adjust the chain slack while it is
in this tightest position.
To check the chain slack the motorcycle must be held
straight up with both wheels on the ground and without rider.
Check the slack at the position shown in the illustration.
Normal slack is approximately 20 ~ 30 mm ( 0.8 ~ 1.2
in). If the slack exceeds 30 mm ( 1.2 in), adjust.
a. 20 ~ 30 mm (0.8 ~ 1.2 in)

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Drive chain slack adjustment
1. Locknut 2. Adjusting bolt
1. Loosen the rear brake pedal free play adjusting nut.
2. Loosen the axle nut.
3. Loosen the chain adjusting locknuts on each chainpuller. To tighten the chain, turn the chain adjusting nuts
in direction  .To loosen the chain turn the chain
adjusting nuts in direction  and push the wheel
forward. Turn each chain adjusting nut exactly the same
amount to maintain correct axle alignment. There are
marks on each chain puller. Use these marks to align
the rear wheel. Too little chain slack will overload the engine and other vital
parts. Keep the slack within the specified limits.
To maintain correct axle alignment, Ensure the notch on
the adjuster is on the same mark on left and right side
4. After adjusting, be sure to tighten each chain adjusting
locknut. The tighten the axle nut to the specified torque
Axle nut torque: 91 N.m (9.1 Kgf.m, 66 lbf.ft)
Locknut torque: 15 N.m (1.5 Kgf.m, 11 lbf.ft)
5. Adjust the free play in the brake pedal.
Check the operation of the brake light after adjusting
the rear brake.
CAUTION:
CAUTION:
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Drive chain slack adjustment
1. Locknut 2. Adjusting bolt
1. Loosen the rear brake pedal free play adjusting nut.
2. Loosen the axle nut.
3. Loosen the chain adjusting locknuts on each chain puller. To tighten the chain, turn the chain adjusting nuts
in direction  .To loosen the chain turn the chain
adjusting nuts in direction  and push the wheel
forward. Turn each chain adjusting nut exactly the same
amount to maintain correct axle alignment. There are
marks on each chain puller. Use these marks to align
the rear wheel. Too little chain slack will overload the engine and other vital
parts. Keep the slack within the specified limits.
To maintain correct axle alignment, Ensure the notch on
the adjuster is on the same mark on left and right side
4. After adjusting, be sure to tighten each chain adjusting
locknut. The tighten the axle nut to the specified torque
Axle nut torque: 91 N.m (9.1 Kgf.m, 66 lbf.ft)
Locknut torque: 15 N.m (1.5 Kgf.m, 11 lbf.ft)
5. Adjust the free play in the brake pedal.
Check the operation of the brake light after adjusting
the rear brake.
CAUTION:
CAUTION:

6-26
Periodically inspect the condition of the steering. Worn out
or loose steering bearings may be dangerous. 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.
Securely support the motorcycle so there is no danger
of it falling over.Wheel bearings
If 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. The wheel bearings should be inspected
according to the Maintenance Schedule.
Steering inspection
WARNING:
6-26
Periodically inspect the condition of the steering. Worn out
or loose steering bearings may be dangerous. 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.
Securely support the motorcycle so there is no danger
of it falling over. Wheel bearings
If 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. The wheel bearings should be inspected
according to the Maintenance Schedule.
Steering inspection
WARNING:

6-33
It is advisable to have a Yamaha dealer service the
wheel.
Securely support the motorcycle so there is no danger
of it falling over. Front wheel removal
1. Place the motorcycle on the centerstand.
2. Remove the speedometer cable.
3. Remove the axle nut and axle.
NOTE:
Do not depress the brake lever when the disc is off the
caliper as the brake pads will be forced shut.
1. Axle nut 2. Speedometer cable
CAUTION:
6-33
It is advisable to have a Yamaha dealer service the
wheel.
Securely support the motorcycle so there is no danger
of it falling over. Front wheel removal
1. Place the motorcycle on the centerstand.
2. Remove the speedometer cable.
3. Remove the axle nut and axle.
NOTE:
Do not depress the brake lever when the disc is off the
caliper as the brake pads will be forced shut.
1. Axle nut 2. Speedometer cable
CAUTION:

6-34
Front wheel installationWhen installing the front wheel, reverse the removal
procedures.
Pay attention to the following points:
1. Make sure that wheel boss and speedometer gear be installed with their projection fitted on their respective
slits. Axle nut torque:
59 N.m (5.9 Kgf.m, 43 lb.ft)
2. Make sure the slot inthe brake shoe plate fits over the
stopper on the front fork outer tube.
3. Make sure the axle nut is properly torqued.
6-34
Front wheel installation
When installing the front wheel, reverse the removal
procedures.
Pay attention to the following points:
1. Make sure that wheel boss and speedometer gear be installed with their projection fitted on their respective
slits. Axle nut torque:
59 N.m (5.9 Kgf.m, 43 lb.ft)
2. Make sure the slot inthe brake shoe plate fits over the
stopper on the front fork outer tube.
3. Make sure the axle nut is properly torqued.

6-35
3
21
Rear wheel removal
It is advisable to have a Yamaha dealer service the
wheel.
Securely support the motorcycle so there is no danger
of it falling over.
1. Place the motorcycle on the centerstand.
2. Remove the cotter pin and nut. Then remove the tension
bar from the brake shoe plate.3. Remove the brake adjusting nut and brake rod from
the brake cam lever.
4. Remove the axle nut and axle.
5. Remove the wheel assembly.
1. Nut 2. Cotter pin3. Tension bar
CAUTION:
1. Adjusting Nut 2. Brake Rod 3. Axle Nut
6-35
3
21
Rear wheel removal
It is advisable to have a Yamaha dealer service the
wheel.
Securely support the motorcycle so there is no danger
of it falling over.
1. Place the motorcycle on the centerstand.
2. Remove the cotter pin and nut. Then remove the tension
bar from the brake shoe plate.3. Remove the brake adjusting nut and brake rod from
the brake cam lever.
4. Remove the axle nut and axle.
5. Remove the wheel assembly.
1. Nut 2. Cotter pin3. Tension bar
CAUTION:
1. Adjusting Nut 2. Brake Rod 3. Axle Nut

6-36
Rear wheel installation
When installing the rear wheel, reverse the removal
procedures. Pay attention to the following points:
1. Adjust the drive chain.
2. Tighten the axle nut and the tension bar nut to the
specified tightening torque.
Axle nut torque: 91 N.m ( 9.1 Kgf.m, 66 lbf.ft)
Tension bar nut: 19 N.m (1.9 Kgf.m, 14 lbf.ft)
3. Adjust the rear brake.
Check the operation of the brake light after adjusting the
rear brake Troubleshooting
Although Yamaha motorcycles receive a rigid inspection
before shipment from the factory, trouble may occur during
operation. Any problem in the fuel, compression, or ignition
systems can cause poor starting and loss of power. The
troubleshooting chart describes a quick, easy, procedure
for making checks. If your motorcycle requires any repair,
bring it to a Yamaha dealer. The skilled technicians at a
Yamaha dealership have the tools, experience, and know-
how to properly service your motorcycle. Use only genuine
Yamaha parts on your motorcycle. Imitation parts may look
like Yamaha parts, but they are often inferior. Consequently,
they have a shorter service life and can lead to expensive
repair bills.
CAUTION:
6-36
Rear wheel installation
When installing the rear wheel, reverse the removal
procedures. Pay attention to the following points:
1. Adjust the drive chain.
2. Tighten the axle nut and the tension bar nut to the
specified tightening torque.
Axle nut torque: 91 N.m ( 9.1 Kgf.m, 66 lbf.ft)
Tension bar nut:
19 N.m (1.9 Kgf.m, 14 lbf.ft)
3. Adjust the rear brake.
Check the operation of the brake light after adjusting the
rear brake Troubleshooting
Although Yamaha motorcycles receive a rigid inspection
before shipment from the factory, trouble may occur during
operation. Any problem in the fuel, compression, or ignition
systems can cause poor starting and loss of power. The
troubleshooting chart describes a quick, easy, procedure
for making checks. If your motorcycle requires any repair,
bring it to a Yamaha dealer. The skilled technicians at a
Yamaha dealership have the tools, experience, and know-
how to properly service your motorcycle. Use only genuine
Yamaha parts on your motorcycle. Imitation parts may look
like Yamaha parts, but they are often inferior. Consequently,
they have a shorter service life and can lead to expensive
repair bills.
CAUTION:

7-1
CLEANING AND STORAGE
A. CLEANING
Frequent, thorough cleaning of your motorcycle will not only
enhance its appearance but will improve its general
performance and extend the useful life of many components.
1. Before cleaning the motorcycle:
a. Block off the end of the exhaust pipe to prevent water entry; a plastic bag and strong rubber band may be
used.
b. Make sure the spark plug and all filler caps are properly
installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply degreaser
to the chain, sprockets, or wheel axles.
3. Rinse the dirt and degreaser off with a garden hose, Use only enough pressure to do the job.
Excessive hose pressure may cause water seepage and
deterioration of wheel bearings, front fork, brakes,
transmission seals and electrical parts. Many expensive repair bills have resulted from improper
high pressure detergent applications such as those
available in coin-operated car washers.
4. Once the majority of the dirt has been hosed off, wash
all surfaces with warm water and mild, detergent-type
soap. An old toothbrush or bottle brush is handy for
hard-to-get-at places.
5. Rinse the motorcycle off immediately with clean water
and dry all surfaces with a chamois, clean towel, or
soft absorbent cloth.
6. Dry the chain and lubricate it to prevent rust.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive-type wax may be applied to all painted and
chrome-plated surfaces. Avoid combination cleaner-
waxes. Many contain abrasives which may mar the paint
or protective finish. When finished, start the engine and
let it idle for several minutes.
CAUTION:
CAUTION:
7-1
CLEANING AND STORAGE
A. CLEANING
Frequent, thorough cleaning of your motorcycle will not only
enhance its appearance but will improve its general
performance and extend the useful life of many components.
1. Before cleaning the motorcycle:
a. Block off the end of the exhaust pipe to prevent water entry; a plastic bag and strong rubber band may be
used.
b. Make sure the spark plug and all filler caps are properly
installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply degreaser
to the chain, sprockets, or wheel axles.
3. Rinse the dirt and degreaser off with a garden hose, Use only enough pressure to do the job.
Excessive hose pressure may cause water seepage and
deterioration of wheel bearings, front fork, brakes,
transmission seals and electrical parts. Many expensive repair bills have resulted from improper
high pressure detergent applications such as those
available in coin-operated car washers.
4. Once the majority of the dirt has been hosed off, wash
all surfaces with warm water and mild, detergent-type
soap. An old toothbrush or bottle brush is handy for
hard-to-get-at places.
5. Rinse the motorcycle off immediately with clean water
and dry all surfaces with a chamois, clean towel, or
soft absorbent cloth.
6. Dry the chain and lubricate it to prevent rust.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive-type wax may be applied to all painted and
chrome-plated surfaces. Avoid combination cleaner-
waxes. Many contain abrasives which may mar the paint
or protective finish. When finished, start the engine and
let it idle for several minutes.
CAUTION:
CAUTION:

7-2 B. STORAGE
Long term storage (30 days or more) of your machine will
require some preventive procedures to guard against
deterioration. After thoroughly cleaning the machine,
prepare for storage as follows:
1. Drain the fuel tank, fuel lines, and carburetor float
bowl(s).
2. Remove the spark plug(s), pour about one tablespoon
of SAE 20W50 motor oil in the spark plug hole(s) and
reinstall the spark plug(s).
Crank the engine over several times (with the
ignition off) to coat the cylinder walls with oil.
3. Remove the drive chain. Clean it thoroughly with
solvent and lubricate it.
Reinstall the chain or store it in a plastic bag
(tied to frame for safe-keeping).
4. Lubricate all control cables.
5. Block up the frame to raise both wheels off the
ground.
6. Tie a plastic bag over the exhaust pipe outlet to
prevent moisture from entering.7. If storing in a humid or salt-air atmosphere, coat
all exposed metal surfaces with a light film of
oil. Do not apply oil to any rubber parts or the
seat cover.
8. Remove the battery and charge it. Store it in a dry place
and recharge it once a month. Do not store the battery
in an excessively warm or cold place (less than 0ºC
(30ºF) or more than 30ºC (90ºF).
NOTE:
Make any necessary repairs before storing the machine.
7-2 B. STORAGE
Long term storage (30 days or more) of your machine will
require some preventive procedures to guard against
deterioration. After thoroughly cleaning the machine,
prepare for storage as follows:
1. Drain the fuel tank, fuel lines, and carburetor float
bowl(s).
2. Remove the spark plug(s), pour about one tablespoon
of SAE 20W50 motor oil in the spark plug hole(s) and
reinstall the spark plug(s).
Crank the engine over several times (with the
ignition off) to coat the cylinder walls with oil.
3. Remove the drive chain. Clean it thoroughly with
solvent and lubricate it.
Reinstall the chain or store it in a plastic bag
(tied to frame for safe-keeping).
4. Lubricate all control cables.
5. Block up the frame to raise both wheels off the
ground.
6. Tie a plastic bag over the exhaust pipe outlet to
prevent moisture from entering.7. If storing in a humid or salt-air atmosphere, coat
all exposed metal surfaces with a light film of
oil. Do not apply oil to any rubber parts or the
seat cover.
8. Remove the battery and charge it. Store it in a dry place
and recharge it once a month. Do not store the battery
in an excessively warm or cold place (less than 0ºC
(30ºF) or more than 30ºC (90ºF).
NOTE:
Make any necessary repairs before storing the machine.

8-1
SPECIFICATIONS
MODEL YBR 125 ED
Dimension: Overall length 1,980 mm ( 78 in)
Overall width 745 mm ( 29 in)
Overall height 1,050 mm ( 41 in)
Seat height 780 mm ( 31 in)
Wheel base 1,290 mm ( 51 in)
Minimum ground clearance 175 mm ( 7 in)
Basic weight: 108 Kg ( 238 lb)
With oil and without fuel: 119 Kg ( 262 lb)
Minimum turning radius: 1,750 mm ( 70 in)
Engine: Type Air cooled, 4-stroke gasoline, SOHC
Cylinder arrangement Single cylinder, Forward inclined
Displacement 123.7 cm
3
Bore x Stroke 54 x 54 mm ( 2.13 x 2.13 in)
Compression rate 10.0 : 1
Starting system Electric starter
Lubrication system Wet sump
8-1
SPECIFICATIONS
MODEL YBR 125 ED
Dimension: Overall length 1,980 mm ( 78 in)
Overall width 745 mm ( 29 in)
Overall height 1,050 mm ( 41 in)
Seat height 780 mm ( 31 in)
Wheel base 1,290 mm ( 51 in)
Minimum ground clearance 175 mm ( 7 in)
Basic weight: 108 Kg ( 238 lb)
With oil and without fuel: 119 Kg ( 262 lb)
Minimum turning radius: 1,750 mm ( 70 in)
Engine: Type Air cooled, 4-stroke gasoline, SOHC
Cylinder arrangement Single cylinder, Forward inclined
Displacement 123.7 cm
3
Bore x Stroke 54 x 54 mm ( 2.13 x 2.13 in)
Compression rate 10.0 : 1
Starting system Electric starter
Lubrication system Wet sump