2018 YAMAHA MT-125 engine coolant

Table of contents
Safety information............................1-1
Description........................................2-1
Left view ..........................................2-1
Right view........................................2-2
Controls and instruments ................2-3
Instrument and control functions....3-1
Main switch/steering lock ...............3-1
Indicator lights and warning
lights ............................................3-2
Multi-function meter unit .................3-4
Handlebar switches.......................3-12
Clutch lever ...................................3-13
Shift pedal .....................................3-14
Brake lever ....................................3-14
Brake pedal ...................................3-15
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-17
Catalytic converter ........................3-18
Rider seat ......................................3-19
Sidestand ......................................3-20
Ignition circuit cut-off system........3-20
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Starting the engine ..........................5-2
Shifting ............................................5-3
Tips for reducing fuel
consumption ................................5-4
Engine break-in ...............................5-4
Parking ............................................5-5
Periodic maintenance and
adjustment........................................6-1
Owner’s tool kit ...............................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4
Removing and installing cowlings ...6-7
Checking the spark plug .................6-8Engine oil and oil filter element ....... 6-9
Coolant ......................................... 6-12
Replacing the air filter element
and cleaning the check hose..... 6-14
Checking the engine idling
speed......................................... 6-14
Adjusting the throttle grip free
play ............................................ 6-15
Valve clearance ............................. 6-16
Tires .............................................. 6-16
Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the front brake lever
free play ..................................... 6-20
Adjusting the brake pedal free
play ............................................ 6-21
Brake light switches ...................... 6-21
Checking the front and rear brake
pads........................................... 6-22
Checking the brake fluid level....... 6-23
Changing the brake fluid............... 6-24
Drive chain slack ........................... 6-24
Cleaning and lubricating the drive
chain .......................................... 6-26
Checking and lubricating the
cables ........................................ 6-26
Checking and lubricating the
throttle grip and cable ............... 6-27
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
brake pedal................................ 6-28
Checking and lubricating the
sidestand ................................... 6-28
Lubricating the swingarm
pivots ......................................... 6-29
Checking the front fork ................. 6-29
Checking the steering ................... 6-30
Checking the wheel bearings ....... 6-30
Battery .......................................... 6-31
Replacing the fuses ...................... 6-32
Replacing the headlight bulb ........ 6-33
Auxiliary lights ............................... 6-35
Tail/brake light .............................. 6-35
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Description
2-1
2
EAU63371
Left view
213
465
1. Battery (page 6-31)
2. Owner’s tool kit (page 6-2)
3. Fuse box (page 6-32)
4. Shift pedal (page 3-14)
5. Engine oil drain bolt (page 6-9)
6. Coolant reservoir (page 6-12)
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Instrument and control functions
3-6
32. Push the “SELECT” button for two
seconds, and the hour digits will
start flashing.
3. Use the “RESET” button to set the
hours.
4. Push the “SELECT” button, and
the minute digits will start flashing.
5. Use the “RESET” button to set the
minutes.
6. Push the “SELECT” button to con-
firm settings and start the clock.
TIP
When setting the hours and minutes, a

creases the increment value one by
one. You may also push and hold the
button to increase the value continu-
ously.
Fuel meter
The fuel meter indicates the amount of
fuel in the fuel tank. The display seg-
ments of the fuel meter disappear from
“F” (full) towards “E” (empty) as the fuel
level decreases. When the fuel level
becomes low, the last segment will
flash and the fuel level warninglight “ ” will come on (“LOW FUEL”
message will also appear). Refuel as
soon as possible.
TIP
If a problem is detected in the fuel me-
ter electrical circuit, all display seg-
ments of the fuel meter will flash eight
times, then go off for 3 seconds, re-
peatedly. If this occurs, have your
Yamaha dealer check the vehicle.
Coolant temperature meter
The coolant temperature meter indi-
cates the temperature of the coolant,
and therefore the engine. When the
coolant temperature is at its upper lim-
it, the second segment from the top
will start to flash. Should this occur, re-
duce the load on the engine by riding at
a moderate pace, at low rpm, until the
coolant temperature goes down. If the
top two segments and “ ” start flash-
ing (“HIGH TEMP” message will also
appear), stop the vehicle and let the
engine cool.
1. Fuel meter
2. Fuel level warning light “ ”
3. Fuel reserve tripmeter
4. Information display
Lo
Hi
1/2
x1000r/min
ZAUM1303
km/h
FTRIP
21
34
1. Coolant temperature warning indicator Ž
2. Information display
3. Coolant temperature meter
Lo
Hi
ZAUM1304
31
2
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Instrument and control functions
3-7
3
NOTICE
ECA10022
Do not continue to operate the en-
gine if it is overheating.
TIP
Coolant temperature varies with
changes in the weather and en-
gine load.
The radiator fan will automatically
switch on or off according to the
coolant temperature.
If the engine overheats, see page
6-39 for further instruction.
Odometer and tripmeter display
The odometer and tripmeter display is
equipped with:
an odometer
two tripmeters
a fuel reserve tripmeter
Push the “SELECT” button to switch
between the odometer and the tripme-
ters in the following order:
ODO (odometer) → TRIP 1 (tripmeter)
→ TRIP 2 (tripmeter) → ODO (odome-
ter)When approximately 3.0 L (0.79 US
gal, 0.66 Imp.gal) of fuel remains in the
fuel tank, the display will automatically
change to the fuel reserve tripmeter
mode “F TRIP” and start counting the
distance traveled from that point. In
this case, push the “SELECT” button
to switch the display in the following
order:
F TRIP → ODO → TRIP 1 → TRIP 2 →
F TRIP
To manually reset a tripmeter, select it
with the “SELECT” button, and then
push the “RESET” button for two sec-
onds.
TIP
The fuel reserve tripmeter will re-
set automatically and disappear
after you have refueled and turned
the key to “OFF”.
The tripmeters will automatically
reset and continue counting after
999.9 is reached.
The odometer will lock at 199999
and cannot be reset.
1. Odometer/tripmeter/fuel reserve tripmeter
1/2
ZAUM1305
TRIP1
1
1. Odometer/tripmeter/fuel reserve tripmeter
1/2
ZAUM1306
F TRIP
1
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For your safety – pre-operation checks
4-1
4
EAU63440
Inspect your vehicle each time you use it to make sure the vehicle is in safe oper-
ating condition. Always follow the inspection and maintenance procedures and
schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility
of an accident or equipment damage. Do not operate the vehicle if you find
any problem. If a problem cannot be corrected by the procedures provided
in this manual, have the vehicle inspected by a Yamaha dealer.
Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel• Check fuel level in fuel tank.
• Refuel if necessary.
• Check fuel line for leakage.3-17
Engine oil• Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage.6-9
Coolant• Check coolant level in reservoir.
• If necessary, add recommended coolant to specified
level.
• Check cooling system for leakage.6-12
Front brake• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic
system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage.6-22,
6-23
Rear brake• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic
system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage.6-22,
6-23
Clutch• Check operation.
• Lubricate cable if necessary.
• Check lever free play.
• Adjust if necessary.6-19
Throttle grip• Make sure that operation is smooth.
• Check throttle grip free play.
• If necessary, have Yamaha dealer adjust throttle grip
free play and lubricate cable and grip housing.6-15,
6-27
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Periodic maintenance and adjustment
6-6
6
EAU72740
TIP
The air filter needs more frequent service if you are riding in unusually wet or
dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
25 Engine oil• Change (warm engine before
draining).At the initial interval and when
the oil change indicator flashes
or comes on
• Check oil level and vehicle for oil
leakage.Every 3000 km (1800 mi)
26Engine oil filter el-
ement• Replace.√√√
27*Cooling system• Check coolant level and vehicle
for coolant leakage.√√√√√
• Change. Every 3 years
28*Front and rear
brake switches• Check operation.√√√√√√
29*Moving parts and
cables• Lubricate.√√√√√
30*Throttle grip hous-
ing and cable• Check operation and free play.
• Adjust the throttle cable free
play if necessary.
• Lubricate the throttle grip hous-
ing and cable.√√√√√
31*Lights, signals and
switches• Check operation.
• Adjust headlight beam.√√√√√√ NO. ITEM
X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READING
ANNUAL CHECK
16121824
0.6 3.5 7 10.5 14
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Periodic maintenance and adjustment
6-12
613. Turn the engine off, and then
check the oil level and correct it if
necessary.
14. Reset the oil change indicator.
(See page 3-10.)
EAU20071
Coolant
The coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUM1726To check the coolant level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
TIP
The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.
2. Check the coolant level in the
coolant reservoir.
TIP
The coolant should be between the
minimum and maximum level marks.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
ZAUM1207
FULL
LOW2
3
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Periodic maintenance and adjustment
6-13
6 3. If the coolant is at or below the
minimum level mark, remove
cowling A (See page 6-7.), and
then open the reservoir cap.
WARNING! Remove only the
coolant reservoir cap. Never at-
tempt to remove the radiator
cap when the engine is hot.
[EWA15162]
4. Add coolant to the maximum level
mark, and then close the reservoir
cap. NOTICE: If 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.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possible, other-
wise the cooling system will not
be protected against frost and
corrosion. If water has been
added to the coolant, have a
Yamaha dealer check the anti-
freeze content of the coolant as
soon as possible, otherwise the
effectiveness of the coolant will
be reduced.
[ECA10473]
5. Install the cowling.
EAU33032Changing the coolant
The coolant must be changed at the in-
tervals specified in the periodic mainte-
nance and lubrication chart. Have a
Yamaha dealer change the coolant.WARNING! Never attempt to remove
the radiator cap when the engine is
hot.
[EWA10382]
Coolant reservoir capacity (up to
the maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
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