2002 YAMAHA DT125R cooling

4-1
EAU01114
PRE-OPERATION CHECKS
4The condition of a vehicle is the owner’s responsibility. Vital components can start to deteriorate quickly and unexpect-
edly, even if the vehicle remains unused (for example, as a result of exposure to the elements). Any damage, fluid leak-
age or loss of tire air pressure could have serious consequences. Therefore, it is very important, in addition to a thor-
ough visual inspection, to check the following points before each ride.
EAU03439
Pre-operation check list
ITEM CHECKS PAGE
Fuel•Check fuel level in fuel tank.
•Refuel if necessary.
•Check fuel line for leakage.3-5–3-7
2-stroke engine oil•Check oil level in oil tank.
•If necessary, add recommended oil to specified level.
•Check vehicle for oil leakage.3-8
Transmission oil•Check oil level in transmission case.
•If necessary, add recommended oil to specified level.6-10–6-12
Coolant•Check coolant level in reservoir.
•If necessary, add recommended coolant to specified level.
•Check cooling system for leakage.6-12–6-15
Front brake•Check operation.
•If soft or spongy, have Yamaha dealer bleed hydraulic system.
•Check lever free play.
•Adjust if necessary.
•Check fluid level in reservoir.
•If necessary, add recommended brake fluid to specified level.
•Check hydraulic system for leakage.3-5, 6-23, 6-24–6-26
Rear brake•Check operation.
•If soft or spongy, have Yamaha dealer bleed hydraulic system.
•Check fluid level in reservoir.
•If necessary, add recommended brake fluid to specified level.
•Check hydraulic system for leakage.3-5, 6-23–6-26
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6-4
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU03884
NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake service
9Regularly check and, if necessary, correct the brake fluid level.
9Every two years replace the internal components of the brake master cylinders and calipers, and change the
brake fluid.
9Replace the brake hoses every four years and if cracked or damaged.21
*Carburetor•Check starter (choke) operation.
•Adjust engine idling speed.√√√√√ √
22*Autolube pump•Check operation.
•Bleed if necessary.√√√√
23 Transmission oil•Check oil level.√√√√√ √
•Change.√√
24*Cooling system•Check coolant level and vehicle for coolant leakage.√√√√ √
•Change.Every 3 years
25*Front and rear brake
switches•Check operation.√√√√√ √
26 Moving parts and cables•Lubricate.√√√√ √
27*Lights, signals and
switches•Check operation.
•Adjust headlight beam.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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6-13
PERIODIC MAINTENANCE AND MINOR REPAIR
64. If the coolant is at or below the
minimum level mark, open the
reservoir cap, add coolant to the
maximum level mark, and then
close the reservoir cap.
EW000067
wNever attempt to remove the radia-
tor cap when the engine is hot.5. Install the panel.NOTE:
If the engine overheats, see page
6-45 for further instructions.
EC000080
cC8If coolant is not available, use
distilled water or soft tap water
instead. Do not use hard water
or salt water since it is harmful
to the engine.
8If water has been used instead
of coolant, replace it with
coolant as soon as possible,
otherwise the engine may not
be sufficiently cooled and the
cooling system will not be pro-
tected against frost and corro-
sion.
8If water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content of
the coolant as soon as possi-
ble, otherwise the effective-
ness of the coolant will be
reduced.
Coolant reservoir capacity:
0.35 L
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6-14
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU03101
Changing the coolant1. Put the motorcycle on a level
place.
2. Remove cowling B and panel A.
(See page 6-6–6-8 for cowling
and panel removal and installa-
tion procedures.)
3. Remove the radiator cap stopper
bolt and the radiator cap.
12
1. Radiator stopper bolt
2. Radiator cap
5. Disconnect the reservoir tank
hose on the reservoir tank side
and drain the coolant from the
reservoir tank.
6. After draining the coolant, thor-
oughly flush the cooling system
with clean tap water.
7. Replace the coolant drain bolt
washer if it is damaged and tight-
en the coolant drain bolt to the
specified torque.
1
1. Reservoir tank hose
4. Place a container under the
engine and remove the coolant
drain bolt.
1
1. Coolant drain bolt
Tightening torque:
Coolant drain bolt:
10 Nm (1.0 m0kgf)
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6-15
PERIODIC MAINTENANCE AND MINOR REPAIR
68. Install the reservoir tank hose.
9. Pour the recommended coolant
into the radiator until it is full.10. Install the radiator cap.
11. Run the engine several minutes.
Stop the engine and recheck the
coolant level in the radiator. If it
is low, add more coolant until it
reaches the top of the radiator.
12. Install the radiator cap stopper
bolt.
13. Fill the reservoir tank with
coolant up to maximum level.
14. Install the reservoir tank cap and
check for coolant leakage.
NOTE:
If any leakage is found, ask a
Yamaha dealer to inspect the cooling
system.15. Install the cowling and the panel.
EC000080
cC8If coolant is not available, use
distilled water or soft tap water
instead. Do not use hard water
or salt water since it is harmful
to the engine.
8If water has been used instead
of coolant, replace it with
coolant as soon as possible,
otherwise the engine may not
be sufficiently cooled and the
cooling system will not be pro-
tected against frost and corro-
sion.
8If water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content of
the coolant as soon as possi-
ble, otherwise the effective-
ness of the coolant will be
reduced.
Recommended antifreeze:
High quality ethylene glycol
antifreeze containing corrosion
inhibitors for aluminum engines.
Antifreeze and water mixing ratio:
1:1
Total amount:
1.05 L
Reservoir tank capacity:
0.35 L
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6-45
PERIODIC MAINTENANCE AND MINOR REPAIR
6
Wait until the
Check the coolant level in the
Level is OK.Level is low, check the
NoLeakage.
Ask a Yamaha dealer to inspectAdd coolant. (See NOTE.)
Restart the engine. If the engine overheats again, ask a
engine has cooled.reservoir tank and/or radiator.cooling system for leakage.
Yamaha dealer to inspect and repair the cooling system.leakage.
and repair the cooling system.
4. Engine overheating
EW000070
w8Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
8After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the
hissing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the
cap.NOTE:
If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is changed to the rec-
ommended coolant as soon as possible.
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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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