2015 YAMAHA MT-125 engine overheat

INSTRUMENT AND CONTROL FUNCTIONS
3-6
3 decreases. When the fuel level be-
comes low, the last segment will flash,
(“LOW FUEL” message will also ap-
pear) and the fuel level warning
light “ ” will come on. Refuel as soon
as possible.
TIPThis fuel meter is equipped with a self-
diagnosis system. If a problem is de-
tected in the fuel meter electrical cir-
cuit, the display segments of the fuel
meter will flash eight times, and then
go off for 3 seconds repeatedly. If this
occurs, have a Yamaha dealer check
the electrical circuit.
Coolant temperature meter
With the key in the “ON” position, the
coolant temperature meter indicates
the temperature of the coolant. The
coolant temperature varies with
changes in the weather and engine
load. When the coolant temperature is
near the maximum limit, the second
segment from the top will flash. If the 2
top segments and “ ” start flashing
(“HIGH TEMP” message will also ap-
pear), stop the vehicle and let the en-
gine cool.
NOTICE
ECA10022
Do not continue to operate the en-
gine if it is overheating.TIPFor radiator-fan-equipped vehi-
cles, the radiator fan(s) automati-
cally switch on or off according to
the coolant temperature in the ra-
diator.
If the engine overheats, see page
6-42 for further instruction.Odometer and tripmeter display
The odometer and tripmeter display is
equipped with the following:
1. Coolant temperature warning indicator “ ”
2. Information display
3. Coolant temperature meterZAUM1150
Lo
Hi
1
3
2
1. Odometer/tripmeter/fuel reserve tripmeterZAUM1151
1/2
TRIP1
1
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OPERATION AND IMPORTANT RIDING POINTS
5-3
5
NOTICE
ECA10261
Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long dis-
tances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.
Always use the clutch while
changing gears to avoid dam-
aging the engine, transmission,
and drive train, which are not
designed to withstand the
shock of forced shifting.
EAU16811
Tips for reducing fuel con-
sumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
Shift up swiftly, and avoid high en-
gine speeds during acceleration.
Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the en-
gine.
Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at traf-
fic lights or at railroad crossings).
EAU16831
Engine break-inThere is never a more important period
in the life of your engine than the period
between 0 and 1000 km (600 mi). 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
1000 km (600 mi). The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that
might result in engine overheating
must be avoided.
EAU16983
0–500 km (0–300 mi)
Avoid prolonged operation above 6000
r/min.
After every hour of operation, stop the
engine, and then let it cool for five to
ten minutes.
Vary the engine speed from time to
time. Do not operate the engine at one
set throttle position.
U5D7E4E0.book Page 3 Thursday, July 10, 2014 3:01 PM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-42
6Engine overheating
WARNING
EWA10401
Do 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.
After 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 hiss-
ing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
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 TIP.)
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.
U5D7E4E0.book Page 42 Thursday, July 10, 2014 3:01 PM