2002 YAMAHA TDR 125 engine overheat

3-4
EAU01652
Coolant temperature gaugeWith the key in the “ON” position, the
coolant temperature gauge indicates
the temperature of the coolant. The
coolant temperature varies with
changes in the weather and engine
load. If the needle reaches or enters
the red zone, stop the motorcycle
and let the engine cool. (See page
6-43 for further instructions.)
EC000002
cCDo not operate the engine if it is
overheated.
EAU00118
Handlebar switches
EAU03898
Light switch “
9/
'
/:”
Set this switch to “'
” to turn on
the auxiliary light, meter lighting and
taillight. Set the switch to “:” to turn
on the headlight also. Set the switch
to “
9” to turn off all the lights.
EAU03888
Dimmer switch “&/%”
Set this switch to “&” for the high
beam and to “%” for the low beam.
EAU03889
Turn signal switch “4/6”
To signal a right-hand turn, push this
switch to “6”. To signal a left-hand
turn, push this switch to “4”. When
released, the switch returns to the
center position. To cancel the turn
signal lights, push the switch in after
it has returned to the center position.
EAU00129
Horn switch “*”
Press this switch to sound the horn.
INSTRUMENT AND CONTROL FUNCTIONS
3
2 1
1
2
3
4
1. Coolant temperature gauge
2. Red zone1. Light switch “
9/
'
/:”
2. Dimmer switch “&/%”
3. Turn signal switch “4/6”
4. Horn switch “*”
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5-4
OPERATION AND IMPORTANT RIDING POINTS
5
EAU00424
Tips for reducing fuel
consumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Thoroughly warm up the engine.
8Turn the starter (choke) off as
soon as possible.
8Shift up swiftly, and avoid high
engine speeds during accelera-
tion.
8Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the
engine.
8Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad cross-
ings).
EAU00436
Engine break-inThere is never a more important peri-
od in the life of your engine than the
period between 0 and 1,000 km. For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do
not put an excessive load on it for the
first 1,000 km. The various parts in
the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheat-
ing must be avoided.
EAU00453
0–500 km
8Avoid prolonged operation above
6,000 r/min.
8After every hour of operation,
stop the engine, and then let it
cool for five to ten minutes.
8Vary the engine speed from time
to time. Do not operate the
engine at one set throttle posi-
tion.
500–1,000 km
8Avoid prolonged operation
above 7,000 r/min.
8Rev the engine freely through
the gears, but do not use full
throttle at any time.
EC000060
cCAfter 1,000 km of operation, the
transmission oil must be changed.
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6-11
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EW000067
wNever attempt to remove the radia-
tor cap when the engine is hot.NOTE:
If the engine overheats, see page
6-43 for further instructions.
EAU03746
To change the coolant
1. Place the motorcycle on a level
surface and let the engine cool if
necessary.
2. Remove the seat. (See page
3-12 for seat removal and instal-
lation procedures.)
3. Remove cowling B. (See page
6-6 for cowling removal and
installation procedures.)
4. Remove the radiator cap.
EW000067
wNever attempt to remove the radia-
tor cap when the engine is hot.
5. Place a container under the
engine to collect the used
coolant.
6. Remove the coolant drain bolt
and disconnect the hose on the
side of the reservoir to drain the
reservoir.
7. After the coolant is completely
drained, thoroughly flush the
cooling system with clean tap
water.
8. Install the coolant drain bolt, and
then tighten it to the specified
torque.
1
1
1. Radiator cap 1. Coolant drain bolt
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6-43
PERIODIC MAINTENANCE AND MINOR REPAIR
6
NOTE:
If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended
coolant as soon as possible.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.Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See NOTE.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
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