2020 YAMAHA MT-125 radiator

Instrument and control functions
3-3
3 For vehicles with a radiator fan, the ra-
diator fan(s) automatically switch on or
off according to the coolant tempera-
ture.
TIP
When the vehicle is turned on, the light
will come on for a few seconds, and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle.
NOTICE
ECA10022
Do not continue to operate the en-
gine if it is overheating.
EAU73172Engine trouble warning light “ ”
This warning light comes on if a prob-
lem is detected in the engine or other
vehicle control system. If this occurs,
have a Yamaha dealer check the on-
board diagnostic system.
TIP
When the vehicle is turned on, the light
will come on for a few seconds and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle.
EAU69895ABS warning light “ ”
This warning light comes on when the
vehicle is first turned on, and goes off
after starting riding. If the warning light
comes on while riding, the anti-lock
brake system may not work correctly.
WARNING
EWA16043
If the ABS warning light does not
turn off after reaching 10 km/h (6
mi/h), or if the warning light comes
on while riding:
Use extra caution to avoid pos-
sible wheel lock during emer-
gency braking.
Have a Yamaha dealer check
the vehicle as soon as possible.
EAU80372Shift light
This light can be set to come on and go
off at select engine speeds. (See page
3-9.)
TIP
When the vehicle is turned on, the light
will come on for a few seconds and
then go off. If the light does not come
on, have a Yamaha dealer check the
vehicle.
ABS
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Periodic maintenance and adjustment
6-12
65. If the coolant is at or below the
minimum level mark, remove the
coolant reservoir cap protector by
removing the bolt then remove the
coolant reservoir cap.
6. Add coolant to the maximum level
mark, and then install the coolant
reservoir cap. WARNING! Re-move only the coolant reservoir
cap. Never attempt to remove
the radiator cap when the en-
gine is hot.
[EWA15162] NOTICE: If
coolant is not available, use dis-
tilled water or soft tap water in-
stead. 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 coolant as soon as possi-
ble, otherwise the cooling sys-
tem will not be protected
against frost and corrosion. If
water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content of
the coolant as soon as possible,
otherwise the effectiveness of
the coolant will be reduced.
[ECA10473]
7. Install the coolant reservoir cap
protector.
8. 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]
1. Coolant reservoir
2. Maximum level mark
3. Minimum level mark
1. Coolant reservoir cap protector
1. Coolant reservoir cap
Coolant reservoir capacity (up to
the maximum level mark):
0.15 L (0.16 US qt, 0.13 Imp.qt)
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Periodic maintenance and adjustment
6-37
6
EAU86430Engine overheating
WARNING
EWAT1041
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.
Place a thick rag, like a towel, over the radiator cap, and then slowly ro-
tate the cap counterclockwise to the detent to allow any residual pres-
sure to escape. When the hissing sound has stopped, press down on the
cap while turning it counterclockwise, and then remove the cap.
TIP
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.
Wait until the engine
has cooled.
Check the coolant
level in the reservoir
and radiator.Add coolant.
(See TIP.)
The coolant level is
OK.
There is no leakage.
There is leakage.
The coolant level is
low.
Check the cooling
system for leakage.
Have a Yamaha
dealer check and
repair the cooling
system.
Start the engine. If the engine overheats again,
have a Yamaha dealer check and repair the cooling
system.
UB6GE0E0.book Page 37 Wednesday, August 28, 2019 11:11 AM

Specifications
8-1
8
Dimensions:
Overall length:
1960 mm (77.2 in)
Overall width:
800 mm (31.5 in)
Overall height:
1065 mm (41.9 in)
Seat height:
810 mm (31.9 in)
Wheelbase:
1325 mm (52.2 in)
Ground clearance:
160 mm (6.30 in)
Minimum turning radius:
2.9 m (9.51 ft)
Weight:
Curb weight:
140 kg (309 lb)
Engine:
Combustion cycle:
4-stroke
Cooling system:
Liquid cooled
Valve train:
SOHC
Number of cylinders:
Single cylinder
Displacement:
124 cm³
Bore × stroke:
52.0 × 58.6 mm (2.05 × 2.31 in)
Starting system:
Electric starter
Engine oil:
Recommended brand:
SAE viscosity grades:
10W-40
Recommended engine oil grade:
API service SG type or higher, JASO
standard MA
Engine oil quantity:
Oil change:
0.85 L (0.90 US qt, 0.75 Imp.qt)
With oil filter removal:
0.95 L (1.00 US qt, 0.84 Imp.qt)
Coolant quantity:
Coolant reservoir (up to the maximum level
mark):
0.15 L (0.16 US qt, 0.13 Imp.qt)
Radiator (including all routes):
0.49 L (0.52 US qt, 0.43 Imp.qt)
Fuel:
Recommended fuel:
Unleaded gasoline (E10 acceptable)
Octane number (RON):
95
Fuel tank capacity:
10 L (2.6 US gal, 2.2 Imp.gal)
Fuel reserve amount:
3.0 L (0.79 US gal, 0.66 Imp.gal)
Fuel injection:
Throttle body:
ID mark:
B5G1 00
Drivetrain:
Gear ratio:
1st:
2.833 (34/12)
2nd:
1.875 (30/16)
3rd:
1.364 (30/22)
4th:
1.143 (24/21)
5th:
0.957 (22/23)
6th:
0.840 (21/25)
Front tire:
Type:
Tubeless
Size:
100/80-17M/C 52S
Manufacturer/model:
MICHELIN PILOT STREET
Rear tire:
Type:
Tubeless
Size:
140/70-17M/C 66S
Manufacturer/model:
MICHELIN PILOT STREET
Loading:
Maximum load:
180 kg (397 lb)
UB6GE0E0.book Page 1 Wednesday, August 28, 2019 11:11 AM