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98Use only the designated quality
brake fluid. Otherwise, the rub-
ber seals may deteriorate, caus-
ing leakage and poor brake per-
formance.
NOTE:
If DOT 4 is not available, DOT 3 can
be used.
EAU00732
Inspecting the brake fluid
levelInsufficient brake fluid may let air
enter the brake system, possibly
causing the brakes to become inef-
fective.
Before riding, check that the brake
fluid is above the minimum level and
fill when necessary.
Observe these precautions:
8When checking the fluid level,
make sure the top of the master
cylinder is level by turning the
handlebars.
1
1.Minimum level mark FRONT
1
1.Minimum level markREARRecommended brake fluid:
DOT 4
8Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor brake performance.
8Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the fluid
and may result in vapor lock.
8Brake fluid may deteriorate paint-
ed surfaces or plastic parts.
Always clean up spilled fluid
immediately.
8Have a Yamaha dealer check
the cause if the brake fluid level
goes down.
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EC000096
cCToo little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits.3.Tighten the wheel axle nut to the
specified torque.
EAU01533*
Drive chain slack adjustment1.Loosen the wheel axle nut.
2.To tighten the chain, turn the
chain adjusting plates in direction
a. To loosen the chain, turn the
chain adjusting plates in direction
band push the wheel forward.
Turn each chain adjusting plate
to exactly the same position to
maintain correct axle alignment.
a b
2
1
1.Wheel axle nut
2.Chain adjusting plate
Tightening torque:
Wheel axle nut:
90 Nm (9.0 m
0kg)
EAU03006
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. This
motorcycle is equipped with a sealed
type chain. Steam cleaning, high-
pressure washers, and solvents can
damage the drive chain, so do not
use these for cleaning it. Use only
kerosene to clean the drive chain.
Wipe it dry, and thoroughly lubricate it
with SAE 30 ~ 50W motor oil. Do not
use any other lubricants on the drive
chain. They may contain solvents
that could damage the sealed chain.
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EAU01038
SPECIFICATIONS
Specifications
ModelDT125R
Dimensions
Overall length2,170 mm
2,235 mm (N, S, SF, CH, A only)
Overall width830 mm
Overall height1,255 mm
Seat height885 mm
Wheel base1,415 mm
Ground clearance315 mm
Minimum turning radius2,100 mm
Basic weight (with oil and
full fuel tank)127 kg
129 kg (CH, A only)
Engine
Engine typeLiquid-cooled 2-stroke
Cylinder arrangementForward-inclined single
cylinder
Displacement124 cm
3
Bore ´Stroke56.0 ´50.7 mm Compression ratio6.7:1
Starting systemKick starter
Lubrication systemSeparate lubrication
(Yamaha autolube)
Engine oil (2-cycle)
Type2 stroke engine oil
Capacity
Total amount1.2 L
Transmission oil
TypeSAE 10W30 type SE motor oil
Capacity
Periodic oil change0.75 L
Total amount0.8 L
Radiator capacity
(Including all routes)0.92 L
Air filterWet type element
Fuel
TypeRegular unleaded gasoline
Fuel tank capacity10 L
Reserve amount1.8 L
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SPECIFICATIONS
90 kg load ~ maximum
load*
Front150 kPa (1.50 kg/cm
2, 1.50 bar)
Rear175 kPa (1.75 kg/cm2, 1.75 bar)
Off-road riding
Front125 kPa (1.25 kg/cm2, 1.25 bar)
Rear150 kPa (1.50 kg/cm2, 1.50 bar)
* Load is total weight of cargo, rider, passenger and accessories.
Wheels
Front
TypeSpoke wheel
Size1.60 ´21
Rear
TypeSpoke wheel
Size1.85 ´18
Brakes
Front
TypeSingle disc brake
OperationRight hand operation
FluidDOT 3 or DOT 4Rear
TypeSingle disc brake
OperationRight foot operation
FluidDOT 3 or DOT 4
Suspension
FrontTelescopic fork
RearSwingarm (link suspension)
Shock absorber
FrontCoil spring/oil damper
RearCoil-gas spring/oil damper
Wheel travel
Front270 mm
Rear260 mm
Electrical
Ignition systemC.D.I.
Charging system
TypeC.D.I. magneto
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SPECIFICATIONS
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8-4 Battery
TypeGM3-3B
Voltage, capacity12 V, 3 AH
Headlight typeConventional incandescent bulb
Bulb voltage, wattage ´quantity
Headlight12 V, 45/40 W ´1
Tail / Brake light12 V, 5/21 W ´1
Front flasher light12 V, 21 W ´2
Rear flasher light12 V, 21 W ´2
Auxiliary light12 V, 4 W ´1
12 V, 3.4 W ´1 (GB only)
Meter light12 V, 3.4 W ´2
Neutral indicator light12 V, 3.4 W ´1
High beam indicator light12 V, 3.4 W ´1
Oil level indicator light12 V, 3.4 W ´1
Turn indicator light12 V, 3.4 W ´1
Fuse
Main10 A
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