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3-7
INSTRUMENT AND CONTROL FUNCTIONS
3
EW000130
w8Do not overfill the fuel tank,
otherwise it may overflow
when the fuel warms up and
expands.
8Avoid spilling fuel on the hot
engine.
EAU00185
cCImmediately wipe off spilled fuel
with a clean, dry, soft cloth, since
fuel may deteriorate painted sur-
faces or plastic parts.
EAU04206
Your Yamaha engine has been
designed to use regular unleaded
gasoline with a research octane num-
ber of 91 or higher. If knocking (or
pinging) occurs, use a gasoline of a
different brand or premium unleaded
fuel. Use of unleaded fuel will extend
spark plug life and reduce mainte-
nance costs.
EAU01084
Catalytic converter(for Switzerland and Austria)
This motorcycle is equipped with a
catalytic converter in the exhaust
chamber.
EW000128
wThe exhaust system is hot after
operation. Make sure that the
exhaust system has cooled down
before doing any maintenance
work.
Recommended fuel:
REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity:
Total amount:
10.0 L
Reserve amount:
1.8 L
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3-9
INSTRUMENT AND CONTROL FUNCTIONS
3
ON
With the lever in this position, fuel
flows to the carburetor. Normal riding
is done with the lever in this position.
ON
FUEL
RES
OFF
1
ON
1. Arrow mark positioned over “ON”
RES
This indicates reserve. If you run out
of fuel while riding, move the lever to
this position. Fill the tank at the first
opportunity. Be sure to set the lever
back to “ON” after refueling!
OFF
ONFUEL RES
1
RES
1. Arrow mark positioned over “RES”
EAU03050
Fuel cockThe fuel cock supplies fuel from the
tank to the carburetor while filtering it
also.
The fuel cock has three positions:
OFF
With the lever in this position, fuel will
not flow. Always return the lever to
this position when the engine is not
running.
RES
ONFUEL
OFF
1
1. Arrow mark positioned over “OFF”OFF: closed position
RES: reserve position
ON: normal position
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8-1
EAU01038
SPECIFICATIONS
8
Specifications
Model DT125R
Dimensions
Overall length 2,170 mm
2,235 mm (N, S, SF, CH, A only)
Overall width 830 mm
Overall height 1,255 mm
Seat height 885 mm
Wheel base 1,415 mm
Ground clearance 315 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and
full fuel tank)127 kg
129 kg (CH, A only)
Engine
Engine type Liquid-cooled 2-stroke
Cylinder arrangement Forward-inclined single
cylinder
Displacement 124 cm
3
Bore ×Stroke 56.0 ×50.7 mm Compression ratio 6.7:1
Starting system Kickstarter
Lubrication system Separate lubrication
(Yamaha Autolube)
Engine oil (2-cycle)
Type 2-stroke engine oil
Capacity
Total amount 1.2 L
Transmission oil
Type SAE 10W30 type SE motor oil
Capacity
Periodic oil change 0.75 L
Total amount 0.8 L
Cooling system capacity
(total amount)0.92 L
Air filterWet type element
Fuel
Type REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity 10 L
Reserve amount 1.8 L
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