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)
UBR3E0E0.book Page 13 Friday, June 19, 2015 1:19 PM
Periodic maintenance and adjustment
6-43
6 Engine 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 counter-
clockwise 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.
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.
UBR3E0E0.book Page 43 Friday, June 19, 2015 1:19 PM
Specifications
8-1
8
Dimensions:
Overall length:
1950 mm (76.8 in)
Overall width:
745 mm (29.3 in)
Overall height:
1025 mm (40.4 in)
Seat height:
810 mm (31.9 in)
Wheelbase:
1350 mm (53.1 in)
Ground clearance:
140 mm (5.51 in)
Minimum turning radius:
2500 mm (98.4 in)
Weight:
Curb weight:
138 kg (304 lb) (MT125)
140 kg (309 lb) (MT125-A)
Engine:
Engine type:
Liquid cooled 4-stroke, SOHC
Cylinder arrangement:
Single cylinder
Displacement:
124 cm³
Bore × stroke:
52.0 × 58.6 mm (2.05 × 2.31 in)
Compression ratio:
11.2 : 1
Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:
Recommended brand:
YAMALUBE
Type:
SAE 10W-30, 10W-40, 15W-40, 20W-40 or
20W-50Recommended engine oil grade:
API service SG type or higher, JASO
standard MA
Engine oil quantity:
Without oil filter element replacement:
0.95 L (1.00 US qt, 0.84 Imp.qt)
With oil filter element replacement:
1.00 L (1.06 US qt, 0.88 Imp.qt)
Coolant quantity:
Coolant reservoir (up to the maximum level
mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator (including all routes):
1.00 L (1.06 US qt, 0.88 Imp.qt)
Air filter:
Air filter element:
Dry element
Fuel:
Recommended fuel:
Premium unleaded gasoline (Gasohol (E10)
acceptable)
Fuel tank capacity:
11.5 L (3.04 US gal, 2.53 Imp.gal)
Fuel reserve amount:
3.0 L (0.79 US gal, 0.66 Imp.gal)
Fuel injection:
Throttle body:
ID mark:
5D78 10
Spark plug(s):
Manufacturer/model:
NGK/CR9E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Clutch:
Clutch type:
Wet, multiple-disc
–20 –10 0
1020 30 40 50 C 10 30 50 70 90 110 0 130 F
SAE 10W-30
SAE 15W-40
SAE 20W-40
SAE 20W-50
SAE 10W-40
SAE 10W-50
UBR3E0E0.book Page 1 Friday, June 19, 2015 1:19 PM
10-1
10
Index
A
ABS (for ABS models) .......................... 3-15
ABS warning light (for ABS models)....... 3-2
Air filter element and check hose,
replacing and cleaning ....................... 6-14
Auxiliary lights ...................................... 6-35
B
Battery .................................................. 6-31
Brake and clutch levers, checking and
lubricating .......................................... 6-27
Brake fluid, changing ........................... 6-24
Brake fluid level, checking ................... 6-23
Brake lever ........................................... 3-14
Brake light switches ............................. 6-21
Brake pedal .......................................... 3-14
Brake pedal, checking and
lubricating .......................................... 6-28
Brake pedal free play, adjusting........... 6-21
C
Cables, checking and lubricating ......... 6-26
Care ........................................................ 7-1
Catalytic converter ............................... 3-18
Clutch lever .......................................... 3-13
Clutch lever free play, adjusting ........... 6-19
Coolant ................................................. 6-12
Cowlings, removing and installing ......... 6-7
D
Dimmer switch ..................................... 3-11
Drive chain, cleaning and lubricating ... 6-26
Drive chain slack .................................. 6-24
E
Engine break-in ...................................... 5-4
Engine idling speed, checking ............. 6-14
Engine oil and oil filter element .............. 6-9
Engine stop switch ............................... 3-12
Engine trouble warning light................... 3-2
F
Front and rear brake pads, checking ... 6-22
Front brake lever free play, checking ... 6-20
Front fork, checking ............................. 6-29
Fuel....................................................... 3-16
Fuel consumption, tips for reducing ...... 5-4
Fuel level warning light ........................... 3-2
Fuel tank cap........................................ 3-16
Fuses, replacing ................................... 6-32
H
Handlebar switches.............................. 3-11
Headlight bulb, replacing ..................... 6-34
High beam indicator light ....................... 3-2
Horn switch .......................................... 3-12
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system ............... 3-20
Indicator lights and warning lights .......... 3-2
Info switch ............................................ 3-12
L
License plate light bulb, replacing ........ 6-37
M
Main switch/steering lock ....................... 3-1
Maintenance and lubrication, periodic ... 6-4
Maintenance, emission control
system .................................................. 6-3
Matte color, caution ................................ 7-1
Model label ............................................. 9-1
Multi-function meter unit ........................ 3-4
N
Neutral indicator light.............................. 3-2
P
Parking .................................................... 5-5
Part locations .......................................... 2-1
Pass switch........................................... 3-11
R
Rider seat.............................................. 3-18
S
Safety information................................... 1-1
Shifting .................................................... 5-3
Shift pedal............................................. 3-13
Sidestand .............................................. 3-19
Sidestand, checking and lubricating .... 6-28
Spark plug, checking .............................. 6-8
Specifications ......................................... 8-1
Starting the engine.................................. 5-2
Start switch ........................................... 3-12
Steering, checking ................................ 6-30
Storage ................................................... 7-4
Supporting the motorcycle ................... 6-37
Swingarm pivots, lubricating ................ 6-29
T
Tail/brake light ...................................... 6-36
Throttle grip and cable, checking and
lubricating ........................................... 6-27
Throttle grip free play, adjusting ........... 6-15
Tires ...................................................... 6-16
Tool kit .................................................... 6-2
Troubleshooting .................................... 6-41
Troubleshooting charts ......................... 6-42
Turn signal indicator light ....................... 3-2
Turn signal light bulb, replacing............ 6-36
Turn signal switch ................................. 3-12
UBR3E0E0.book Page 1 Friday, June 19, 2015 1:19 PM