2004 YAMAHA YBR125 check engine

CONTENTS
DESCRIPTION............................................................. 1-1
MACHINE IDENTIFICATION....................................... 2-1
Vehicle identification number ................................. 2-1
Engine serial number............................................ 2-1
CONTROL FUNCTIONS.............................................. 3-1
Main switch ............................................................ 3-1
Indicator lights ........................................................ 3-2
Speedometer..........................................................3-3
Fuel gauge............................................................. 3-3
Handlebar switches over left .................................. 3-4
Handlebar switches over right.............................. 3-5
Clutch lever............................................................ 3-6
Shift pedal............................................................. 3-6
Front brake lever................................................... 3-7
Rear brake pedal................................................... 3-7
Fuel tank cap......................................................... 3-8
Fuel cock............................................................... 3-9
Starter lever......................................................... 3-10
Kick starter .......................................................... 3-10
Steering lock....................................................... 3-11
Seat......................................................................3-12
Side covers......................................................... 3-13
Rear shock absorber adjustment ....................... 3-14
XIPRE-OPERATION CHECKS........................................ 4-1
Engine oil................................................................ 4-3
Tires........................................................................4-3
Fitting/Fasteners....................................................4-6
Switches................................................................ 4-6
Wheels ......................................................... 4-6
Fuel ........................................................... 4-7
OPERATION AND IMPORTANT RIDING POINTS....... 5-1
Starting a cold engine........................................... 5-2
Starting a warm engine .......................................... 5-2
Warming up the engine .......................................... 5-2
Shifting ................................................................... 5-3
Tips for reduccing fuel consumption...................... 5-4
Engine Break-in...................................................... 5-4
Parking ................................................................... 5-5
CONTENTS
DESCRIPTION............................................................. 1-1
MACHINE IDENTIFICATION....................................... 2-1
Vehicle identification number ................................. 2-1
Engine serial number............................................ 2-1
CONTROL FUNCTIONS.............................................. 3-1
Main switch ............................................................ 3-1
Indicator lights ........................................................ 3-2
Speedometer..........................................................3-3
Fuel gauge............................................................. 3-3
Handlebar switches over left .................................. 3-4
Handlebar switches over right.............................. 3-5
Clutch lever............................................................ 3-6
Shift pedal............................................................. 3-6
Front brake lever................................................... 3-7
Rear brake pedal................................................... 3-7
Fuel tank cap......................................................... 3-8
Fuel cock............................................................... 3-9
Starter lever......................................................... 3-10
Kick starter .......................................................... 3-10
Steering lock....................................................... 3-11
Seat......................................................................3-12
Side covers......................................................... 3-13
Rear shock absorber adjustment ....................... 3-14
XIPRE-OPERATION CHECKS........................................ 4-1
Engine oil................................................................ 4-3
Tires........................................................................4-3
Fitting/Fasteners....................................................4-6
Switches................................................................ 4-6
Wheels ......................................................... 4-6
Fuel ........................................................... 4-7
OPERATION AND IMPORTANT RIDING POINTS....... 5-1
Starting a cold engine........................................... 5-2
Starting a warm engine .......................................... 5-2
Warming up the engine .......................................... 5-2
Shifting ................................................................... 5-3
Tips for reduccing fuel consumption...................... 5-4
Engine Break-in...................................................... 5-4
Parking ................................................................... 5-5

PERIODIC MAINTENANCE AND MINOR REPAIRS..... 6-1
Tool kit..................................................................... 6-2
PERIODIC MAINTENANCE/LUBRICATION......... 6-3
Torque specifications............................................. 6-5
Engine oil................................................................ 6-6
Oil pressure............................................................ 6-9
Air filter.................................................................6-10
Carburetor adjustment.........................................6-12
Valve clearance adjustment.................................6-12
Idle speed adjustment..........................................6-13
Throttle cable adjustment....................................6-14
Spark plug inspection...........................................6-15
Front brake adjustment........................................6-16
Checking the brake shoes ...................................6-16
Rear brake adjustment.........................................6-17
Brake light switch adjustment ..............................6-18
Clutch adjustment................................................ 6-18
Drive chain slack check.......................................6-19
Drive chain slack adjustment...............................6-20
Drive chain lubrication..........................................6-21
Cable inspection and lubrication.......................... 6-21
Throttle cable and grip lubrication .......................6-22
Brake and shift pedals .........................................6-22
Brake and clutch levers .......................................6-22
Sidestand.............................................................6-22
Front fork inspection............................................6-23Steering inspection.............................................. 6-24
Wheel bearings.................................................... 6-24
Battery.................................................................. 6-25
Replenishing the battery fluid .............................. 6-26
Storage the battery.............................................. 6-27
Fuse replacement................................................ 6-27
Headlight bulb replacement................................. 6-28
Turn signal bulb replacement.............................. 6-30
Taillight bulb replacement.................................... 6-30
Front wheel removal............................................. 6-31
Front wheel installation........................................ 6-32
Rear wheel removal............................................. 6-32
Rear wheel installation......................................... 6-33
Troubleshooting.................................................... 6-34
Troubleshooting chart.......................................... 6-35
CLEANING AND STORAGE....................................... 7-1
CLEANING............................................................. 7-1
STORAGE.............................................................. 7-2
SPECIFICATIONS ........................................................ 8-1
XII
CONTENTS
DESCRIPTION............................................................. 1-1
MACHINE IDENTIFICATION....................................... 2-1
Vehicle identikfication number ............................... 2-1
Engine serial number............................................ 2-1
CONTROL FUNCTIONS.............................................. 3-1
Main switch ............................................................ 3-1
Indicator lights ........................................................ 3-2
Speedometer..........................................................3-3
Fuel gauge............................................................. 3-3
Handlebar switches over left .................................. 3-4
Handlebar switches over right.............................. 3-5
Clutch lever............................................................ 3-6
Shift pedal............................................................. 3-6
Front brake lever................................................... 3-7
Rear brake pedal................................................... 3-7
Fuel tank cap......................................................... 3-8
Fuel cock............................................................... 3-9
Starter lever......................................................... 3-10
Kick starter .......................................................... 3-10
Steering lock....................................................... 3-11
Seat......................................................................3-12
Side covers......................................................... 3-13
Rear shock absorber adjustment ....................... 3-14
XIPRE-OPERATION CHECKS........................................ 4-1
Engine oil................................................................ 4-3
Tires........................................................................4-3
Fitting/Fasteners....................................................4-6
Switches................................................................ 4-6
Wheels ......................................................... 4-6
Fuel ........................................................... 4-7
OPERATION AND IMPORTANT RIDING POINTS....... 5-1
Starting a cold engine........................................... 5-2
Starting a warm engine .......................................... 5-2
Warming up the engine .......................................... 5-2
Shifting ................................................................... 5-3
Tips for reduccing fuel consumption...................... 5-4
Engine Break-in...................................................... 5-4
Parking ................................................................... 5-5

PRE-OPERATION CHECKS
Before using this motorcycle, check the following points:
ITEM ROUTINE
PAGE
Check operation, condition and free play.
Adjust if necessary
Clutch
Throttle grip / cableCheck for smooth operation.
Lubricate / Adjust if necessary
Check oil level / add oil as necessary
Engine oil
Drive chainCheck chain slack and condition. Lubricate if necessary
Adjust if necessary.
Air filter
Control and meter cableCheck tire pressure, wear, damage and spoke tightness
Check for smooth operation.
Lubricate if necessary6-16 ~ 6-18
6-14 , 6-22
4-3 , 6-6 , 6-9
6-19 ~ 6-21
6-10 ~ 6-11
4-3 ~ 4-6 , 6-31~ 6-33
6-21 Check operation, condition and free play.
Adjust if necessary
Wheels / Tires
Clean and oil it frequently.6-18 Brakes
4-1
PRE-OPERATION CHECKS
Before using this motorcycle, check the following points:
ITEM ROUTINE
PAGE
Check operation, condition and free play.
Adjust if necessary
Clutch
Throttle grip / cableCheck for smooth operation.
Lubricate / Adjust if necessary
Check oil level / add oil as necessary
Engine oil
Drive chainCheck chain slack and condition. Lubricate if necessary
Adjust if necessary.
Air filter
Control and meter cableCheck tire pressure, wear, damage and spoke tightness
Check for smooth operation.
Lubricate if necessary6-16 ~ 6-18
6-14 , 6-22
4-3 , 6-6 , 6-9
6-19 ~ 6-21
6-10 ~ 6-11
4-3 ~ 4-6 , 6-31~ 6-33
6-21 Check operation, condition and free play.
Adjust if necessary
Wheels / Tires
Clean and oil it frequently.6-18 Brakes
4-1

4-2 NOTE:
Pre-operation checks should be made each time the motorcycle is used. Such an inspection can be thoroughly accomplished
in a very short time; and the added safety it assures is more than worth the time involved. If any maintenance service or
adjustment is needed, consult the chart above to refer to the pages in which the service or adjustment is described.
1. The engine, exhaust pipe, and muffler will be very hot after the engine has been run.
Be careful not to touch them or to allow any clothing item to contact them during inspection or repair.
2. If any item is not working properly, have it inspected and repaired before operating the motorcycle.
ITEMROUTINE
PAGE
Sidestand
Fittings / FastenersCheck all chassi fittings and fasteners.
Tighten / Adjust, if necessary
Check fuel level / top up as required.
Fuel tank
Lights, signals and switches
BatteryCheck electrolyte level.
Replenish with ìdistilled waterî if necessary.6-22
4-6 , 6-5
4-6 , 6-28 ~ 6-30
6-25 ~ 6-276-22
4-7
Check for proper operation
Front brake and clutch
lever pivotsCheck for smooth operation.
Lubricate if necessary
Check for smooth operation.
Lubricate if necessary
6-22 Check for smooth operation.
Lubricate if necessary Rear brake and shift pedal
shafts
WARNING:
4-2 NOTE:
Pre-operation checks should be made each time the motorcycle is used. Such an inspection can be thoroughly accomplished
in a very short time; and the added safety it assures is more than worth the time involved. If any maintenance service or
adjustment is needed, consult the chart above to refer to the pages in which the service or adjustment is described.
1. The engine, exhaust pipe, and muffler will be very hot after the engine has been run.
Be careful not to touch them or to allow any clothing item to contact them during inspection or repair.
2. If any item is not working properly, have it inspected and repaired before operating the motorcycle.
ITEMROUTINE
PAGE
Sidestand
Fittings / FastenersCheck all chassi fittings and fasteners.
Tighten / Adjust, if necessary
Check fuel level / top up as required.
Fuel tank
Lights, signals and switches
BatteryCheck electrolyte level.
Replenish with ìdistilled waterî if necessary.6-22
4-6 , 6-5
4-6 , 6-28 ~ 6-30
6-25 ~ 6-276-22
4-7
Check for proper operation
Front brake and clutch
lever pivotsCheck for smooth operation.
Lubricate if necessary
Check for smooth operation.
Lubricate if necessary
6-22 Check for smooth operation.
Lubricate if necessary Rear brake and shift pedal
shafts
WARNING:

4-3
OIL QUANTITY:
Total amount:
1.2 L ( 0.264 Imp gal, 0.317 US gal)
Periodic oil change:
1.0 L ( 0.220 Imp gal, 0.264 US gal) Engine oil (See page 6-6 for details)
Make sure the engine oil is at the specified level. Add oil as
necessary.
Check the oil level in a daily manner and top it up if
necessary.
CAUTION:Tires
To ensure maximum performance, long service, and safe
operation, note the following:
1. Tire air pressure
Always check and adjust the tire pressure before
operating the machine.
Tire inflation pressure should be checked and adjusted
when the temperature of the tire equals the ambient air
temperature.
Tire inflation pressure must be adjusted according to
total weight of cargo, rider, passenger and accessories
(fairing, saddlebags, etc. if approved for this model),
and vehicle speed.
WARNING:
4-3
OIL QUANTITY:
Total amount:
1.2 L ( 0.264 Imp gal, 0.317 US gal)
Periodic oil change:
1.0 L ( 0.220 Imp gal, 0.264 US gal) Engine oil (See page 6-6 for details)
Make sure the engine oil is at the specified level. Add oil as
necessary.
Check the oil level in a daily manner and top it up if
necessary.
CAUTION:Tires
To ensure maximum performance, long service, and safe
operation, note the following:
1. Tire air pressure
Always check and adjust the tire pressure before
operating the machine.
Tire inflation pressure should be checked and adjusted
when the temperature of the tire equals the ambient air
temperature.
Tire inflation pressure must be adjusted according to
total weight of cargo, rider, passenger and accessories
(fairing, saddlebags, etc. if approved for this model),
and vehicle speed.
WARNING:

4-6
1. It is dangerous to ride with a worn-out tire. When
the tire tread begin to show signs of wear, replace
the tire immediately. Brakes, tires and related wheel
parts should be left to a Yamaha dealer.
2. Patching a punctured tube is not recommended. If
it is absolutely necessary to do so, use great care
and replace the tube as soon as possible with a
good quality replacement.
Fitting/Fasteners
Alway check the tightness of chassis fittings and fasteners
before a ride. Use the chart on page 6-5 to find the correct
torque.
Switches
Check the operation of the starter switch, main switch,
ì Engine Stopî switch.
WARNING:Wheels
To 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 or
other qualified mechanic. Do not attempt even small
repairs to the wheel. If a wheel is deformed or cracked,
it must be replaced.
2. Tires 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 tire life.
3. After installing a tire, ride conservatively to allow the
tire to seat itself on the rim properly. Failure to allow
proper seating may cause tire failure, resulting in
damage to the motorcycle and injury to the rider.
4-6
1. It is dangerous to ride with a worn-out tire. When
the tire tread begin to show signs of wear, replace
the tire immediately. Brakes, tires and related wheel
parts should be left to a Yamaha dealer.
2. Patching a punctured tube is not recommended. If
it is absolutely necessary to do so, use great care
and replace the tube as soon as possible with a
good quality replacement.
Fitting/Fasteners
Alway check the tightness of chassis fittings and fasteners
before a ride. Use the chart on page 6-5 to find the correct
torque.
Switches
Check the operation of the starter switch, main switch,
ì Engine Stopî switch.
WARNING:Wheels
To 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 or
other qualified mechanic. Do not attempt even small
repairs to the wheel. If a wheel is deformed or cracked,
it must be replaced.
2. Tires 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 tire life.
3. After installing a tire, ride conservatively to allow the
tire to seat itself on the rim properly. Failure to allow
proper seating may cause tire failure, resulting in
damage to the motorcycle and injury to the rider.

5-2 Starting a cold engine
1. Turn the fuel cock to ìONî.
2. Turn the main switch to ìONî and the engine stop switch
to ì ì.
3. Shift transmission into neutral.
NOTE:
When the transmission is in neutral, the neutral indicator
light should be on. If the light does not come on, ask a
Yamaha dealer to inspect it.
4. Fully open the starter (CHOKE) and completely close
the throttle grip.
5. Kick the starter to start the engine.
6. After starting the engine, turn back the starter to an
intermediate position.
NOTE:
To obtain maximum engine life and service, do not ever
thoroughly accelerate it while the engine is cold.
7. After warming up the engine, turn back the stater
(CHOKE) completely.
NOTE:
The engine is warm when it responds normally to the throttle
with the starter turned off.
Starting a warm engine
The starter lever is not required when the engine is warm.
CAUTION:
If the engine fails to start with the procedures above, try to
start again with the throttle grip opened 1/4 to 1/2.
Warming up the engine
For extended engine life always warm the engine up never
accelerate hard while the engine is cold. To check if engine
temperature is normal, rev the engine with the choke closed
and check to see if it responds normally.
CAUTION:
See the ìBreak-in sectionî prior to operating the motorcycle
for the first time.
5-2 Starting a cold engine
1. Turn the fuel cock to ìONî.
2. Turn the main switch to ìONî and the engine stop switch
to ì ì.
3. Shift transmission into neutral.
NOTE:
When the transmission is in neutral, the neutral indicator
light should be on. If the light does not come on, ask a
Yamaha dealer to inspect it.
4. Fully open the starter (CHOKE) and completely close
the throttle grip.
5. Kick the starter to start the engine.
6. After starting the engine, turn back the starter to an
intermediate position.
NOTE:
To obtain maximum engine life and service, do not ever
thoroughly accelerate it while the engine is cold.
7. After warming up the engine, turn back the stater
(CHOKE) completely.
NOTE:
The engine is warm when it responds normally to the throttle
with the starter turned off.
Starting a warm engine
The starter lever is not required when the engine is warm.
CAUTION:
If the engine fails to start with the procedures above, try to
start again with the throttle grip opened 1/4 to 1/2.
Warming up the engine
For extended engine life always warm the engine up never
accelerate hard while the engine is cold. To check if engine
temperature is normal, rev the engine with the choke closed
and check to see if it responds normally.
CAUTION:
See the ìBreak-in sectionî prior to operating the motorcycle
for the first time.

6-3 PERIODIC MAINTENANCE / LUBRICATION
Wheel bearings* Battery*
Check looseness and damage. Check electrolyte level, routing breather pipe.
ITEM
How it sounds
/ Adjust if necessary.
REMARKS1,000KM
Fuel line Air filter
Carburetor*Valves*
Muffler
Brakes* Engine oil
Steering bearings* Rear arm pivot*Check fuel hose, for cracks or damage.Clean or replace if necessary.
Adjust
Check damage, Retighten.
Check operation, adjust.
Grease the brake cam. Replace / Check level
Check loosenes.
Repack every 12,000 km or 12 month.** Check rear arm assembly for looseness.
Moderately repack.***
EVERY
3,000KM
OR ERERY
6 MONTHS
Wheels* and tires
Check tire pressure, runout and spoke tightness.
Spark plugCheck condition and clean if necessary.
Replace if necessary every 12,000 Km.
3,000KM
6-3 PERIODIC MAINTENANCE / LUBRICATION
Wheel bearings* Battery*
Check looseness and damage. Check electrolyte level, routing breather pipe.
ITEM
How it sounds
/ Adjust if necessary.
REMARKS1,000KM
Fuel line Air filter
Carburetor*Valves*
Muffler
Brakes* Engine oil
Steering bearings* Rear arm pivot*Check fuel hose, for cracks or damage.Clean or replace if necessary.
Adjust
Check damage, Retighten.
Check operation, adjust.
Grease the brake cam. Replace / Check level
Check loosenes.
Repack every 12,000 km or 12 month.** Check rear arm assembly for looseness.
Moderately repack.***
EVERY
3,000KM
OR ERERY
6 MONTHS
Wheels* and tires
Check tire pressure, runout and spoke tightness.
Spark plugCheck condition and clean if necessary.
Replace if necessary every 12,000 Km.
3,000KM