2004 YAMAHA YBR125 engine

Handlebar switches over rigt
1. ìENGINE STOPî switch, shuts the engine off
3-5“ENGINE STOP” switch
The engine stop switch is a safety device for use in an
emergency such as when the motorcycle overturns or if
trouble occurs in the throttle system. Turn the switch to
ì î to start the engine, and turn the switch to ì î to
stop the engine.
Handlebar switches over rigt
1. ìENGINE STOPî switch, shuts the engine off
3-5“ENGINE STOP” switch
The engine stop switch is a safety device for use in an
emergency such as when the motorcycle overturns or if
trouble occurs in the throttle system. Turn the switch to
ì î to start the engine, and turn the switch to ì î to
stop the engine.

The clutch lever is located on the left handlebar. Pull the
clutch lever to the handlebar to disengage the clutch, and
release the lever to engage the clutch. The lever should be
pulled rapidly and released slowly for smooth clutch
operation.
3-6This motorcycle is equipped with a constant-mesh 5-speed
transmission.
The shift pedal is located on the left side of the engine and
is used in combination with the clutch when shifting.
Clutch lever
Shift pedal
1. Clutch lever1. Shift pedal
The clutch lever is located on the left handlebar. Pull the
clutch lever to the handlebar to disengage the clutch, and
release the lever to engage the clutch. The lever should be
pulled rapidly and released slowly for smooth clutch
operation.
3-6This motorcycle is equipped with a constant-mesh 5-speed
transmission.
The shift pedal is located on the left side of the engine and
is used in combination with the clutch when shifting.
Clutch lever
Shift pedal
1. Clutch lever1. Shift pedal

Fuel cock
3-9The fuel cock supplies fuel from the tank to the carburetor
while filtering it also.
The fuel cock has three positions:
OFF: With the fuel cock in this position, fuel will not flow.
Always set the fuel cock to this position when the
engine is not running.
ON: With the fuel cock in this position, fuel flows to the
carburetor. Set the fuel cock to this position when
starting the engine and while riding.
RES: This indicates reserve. If you run out of fuel while
riding, set the fuel cock to this position.
Fill the tank at the first opportunity. be sure to set
fuel cock back to ìONî after refueling!
Fuel cock
3-9The fuel cock supplies fuel from the tank to the carburetor
while filtering it also.
The fuel cock has three positions:
OFF: With the fuel cock in this position, fuel will not flow.
Always set the fuel cock to this position when the
engine is not running.
ON: With the fuel cock in this position, fuel flows to the
carburetor. Set the fuel cock to this position when
starting the engine and while riding.
RES: This indicates reserve. If you run out of fuel while
riding, set the fuel cock to this position.
Fill the tank at the first opportunity. be sure to set
fuel cock back to ìONî after refueling!

Starting a cold engine requires a richer air-fuel mixture. A
separate starter circuit supplies the mixture.
Pull the starter knob up to open the circuit for starting. When
the engine has warmed up, push the knob down to close
the circuit.
3-10 Starter lever
Rotate the kick starter away from the engine. Push the starter
down lightly with your foot until the gears engage, then kick
smoothly and forcefully to start the engine.
Shift to neutral before starting.
Kick starter
1. Starter lever
1. Kick starter
Starting a cold engine requires a richer air-fuel mixture. A
separate starter circuit supplies the mixture.
Pull the starter knob up to open the circuit for starting. When
the engine has warmed up, push the knob down to close
the circuit.
3-10 Starter lever
Rotate the kick starter away from the engine. Push the starter
down lightly with your foot until the gears engage, then kick
smoothly and forcefully to start the engine.
Shift to neutral before starting.
Kick starter
1. Starter lever
1. Kick starter

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.