2020 YAMAHA MT-125 fuel cap

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 .....................................3-13
Brake lever ....................................3-14
Brake pedal ...................................3-14
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-16
Fuel tank overflow hose ................3-18
Catalytic converter ........................3-18
Seat ...............................................3-19
Helmet holder ................................3-20
Sidestand ......................................3-20
Ignition circuit cut-off system........3-21
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Engine break-in ...............................5-1
Starting the engine ..........................5-2
Shifting ............................................5-4
Tips for reducing fuel
consumption ................................5-5
Parking ............................................5-6
Periodic maintenance and
adjustment........................................6-1
Tool kit.............................................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4Removing and installing
cowlings ...................................... 6-7
Checking the spark plug ................. 6-7
Engine oil and oil filter element ....... 6-8
Why Yamalube .............................. 6-11
Coolant ......................................... 6-11
Replacing the air filter element
and cleaning the check hose..... 6-13
Adjusting the engine idling
speed......................................... 6-13
Adjusting the throttle grip free
play ............................................ 6-14
Valve clearance ............................. 6-15
Tires .............................................. 6-15
Cast wheels .................................. 6-18
Adjusting the clutch lever free
play ............................................ 6-18
Checking the front brake lever
free play ..................................... 6-19
Adjusting the brake pedal free
play ............................................ 6-20
Brake light switches ...................... 6-20
Checking the front and rear brake
pads........................................... 6-21
Checking the brake fluid level....... 6-22
Changing the brake fluid............... 6-23
Drive chain slack ........................... 6-23
Cleaning and lubricating the drive
chain .......................................... 6-25
Checking and lubricating the
cables ........................................ 6-25
Checking and lubricating the
throttle grip and cable ............... 6-26
Checking and lubricating the
brake and shift pedals ............... 6-26
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
sidestand ................................... 6-27
Lubricating the swingarm pivots... 6-28
Checking the front fork ................. 6-28
Checking the steering ................... 6-29
Checking the wheel bearings ....... 6-29
Battery .......................................... 6-30
Replacing the fuses ...................... 6-31
Vehicle lights ................................. 6-32
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Safety information
1-5
1 operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires and Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. See page 6-15
for tire specifications and for informa-
tion on servicing and replacing your
tires.
Transporting the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle.
Remove all loose items from the
motorcycle.
Check that the fuel cock (if
equipped) is in the off position and
that there are no fuel leaks.
Shift the transmission into gear
(for models with a manual trans-
mission).
Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mountedhandlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Description
2-1
2
EAU63371
Left view
1234
65798
1. Fuel tank cap (page 3-16)
2. Battery (page 6-30)
3. Fuses (page 6-31)
4. Tool kit (page 6-2)
5. Sidestand (page 3-20)
6. Air filter check hose
7. Shift pedal (page 3-13)
8. Idle adjusting screw (page 6-13)
9. Coolant reservoir (page 6-11)
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Instrument and control functions
3-16
3
EAU13076
Fuel tank cap
To open the fuel tank cap
Open the fuel tank cap lock cover, in-
sert the key into the lock, and then turn
it 1/4 turn clockwise. The lock will be
released and the fuel tank cap can be
opened.
To close the fuel tank cap
With the key still inserted in the lock,
push down the fuel tank cap. Turn the
key 1/4 turn counterclockwise, remove
it, and then close the lock cover.
TIP
The fuel tank cap cannot be closed un-
less the key is in the lock. In addition,
the key cannot be removed if the cap is
not properly closed and locked.
WARNING
EWA11092
Make sure that the fuel tank cap is
properly closed after filling fuel.
Leaking fuel is a fire hazard.
EAU13213
Fuel
Make sure there is sufficient gasoline in
the tank.
WARNING
EWA10882
Gasoline and gasoline vapors are
extremely flammable. To avoid fires
and explosions and to reduce the
risk of injury when refueling, follow
these instructions.
1. Before refueling, turn off the en-
gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. Stop
filling when the fuel reaches the
bottom of the filler tube. Because
fuel expands when it heats up,
heat from the engine or the sun
can cause fuel to spill out of the
fuel tank.
3. Wipe up any spilled fuel immedi-
ately. NOTICE: Immediately
wipe off spilled fuel with a clean,1. Fuel tank cap lock cover
2. Unlock.
1
2
1. Fuel tank filler tube
2. Maximum fuel level
1
2
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Instrument and control functions
3-17
3 dry, soft cloth, since fuel may
deteriorate painted surfaces or
plastic parts.
[ECA10072]
4. Be sure to securely close the fuel
tank cap.
WARNING
EWA15152
Gasoline is poisonous and can
cause injury or death. Handle gaso-
line with care. Never siphon gasoline
by mouth. If you should swallow
some gasoline or inhale a lot of gas-
oline vapor, or get some gasoline in
your eyes, see your doctor immedi-
ately. If gasoline spills on your skin,
wash with soap and water. If gaso-
line spills on your clothing, change
your clothes.
EAU86072
Your Yamaha engine was designed to
use unleaded gasoline with a research
octane number of 95 or higher. If en-
gine knocking or pinging occurs, use a
gasoline of a different brand or higher
octane rating.
TIP
This mark identifies the recom-
mended fuel for this vehicle as
specified by European regulation
(EN228).
Confirm the gasoline pump nozzle
has the same fuel identification
mark.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that con-
taining methanol. Gasohol containing
ethanol can be used if the ethanol con-
tent does not exceed 10% (E10). Gas-
ohol containing methanol is not
recommended by Yamaha because it
can cause damage to the fuel system
or vehicle performance problems.
NOTICE
ECA11401
Use only unleaded gasoline. The use
of leaded gasoline will cause severe
damage to internal engine parts,
such as the valves and piston rings,
as well as to the exhaust system.
Recommended fuel:
Unleaded gasoline (E10 acceptable)
Octane number (RON):
95
Fuel tank capacity:
10 L (2.6 US gal, 2.2 Imp.gal)
Fuel tank reserve:
3.0 L (0.79 US gal, 0.66 Imp.gal)
E5E10
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Motorcycle care and storage
7-4
7
EAU83472
Storage
Always store the vehicle in a cool, dry
place. If necessary, protect it against
dust with a porous cover. Be sure the
engine and the exhaust system are
cool before covering the vehicle. If the
vehicle often sits for weeks at a time
between uses, the use of a quality fuel
stabilizer is recommended after each
fill-up.
NOTICE
ECA21170
Storing the vehicle in a poorly
ventilated room or covering it
with a tarp, while it is still wet,
will allow water and humidity to
seep in and cause rust.
To prevent corrosion, avoid
damp cellars, stables (because
of the presence of ammonia)
and areas where strong chemi-
cals are stored.
Long term storage
Before storing the vehicle long term (60
days or more):
1. Make all necessary repairs and
perform any outstanding mainte-
nance.
2. Follow all instructions in the Care
section of this chapter.
3. Fill up the fuel tank, adding fuel
stabilizer according to product in-
structions. Run the engine for 5
minutes to distribute treated fuel
through the fuel system.
4. For vehicles equipped with a fuel
cock: Turn the fuel cock lever to
the off position.5. For vehicles with a carburetor: To
prevent fuel deposits from build-
ing up, drain the fuel in the carbu-
retor float chamber into a clean
container. Retighten the drain bolt
and pour the fuel back into the fuel
tank.
6. Use a quality engine fogging oil
according to product instructions
to protect internal engine compo-
nents from corrosion. If engine
fogging oil is not available, per-
form the following steps for each
cylinder:
a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine
oil into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
WARNING! To prevent dam-
age or injury from sparking,
make sure to ground the
spark plug electrodes while
turning the engine over.
[EWA10952]
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
7. Lubricate all control cables, piv-
ots, levers and pedals, as well as
the sidestand and centerstand (if
equipped).
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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)
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10-1
10
Index
A
ABS ....................................................... 3-15
ABS warning light ................................... 3-3
Air filter element and check hose,
replacing and cleaning ....................... 6-13
B
Battery .................................................. 6-30
Brake and clutch levers, checking and
lubricating ........................................... 6-27
Brake and shift pedals, checking and
lubricating ........................................... 6-26
Brake fluid, changing ............................ 6-23
Brake fluid level, checking .................... 6-22
Brake lever ............................................ 3-14
Brake light switches.............................. 6-20
Brake pedal........................................... 3-14
Brake pedal free play, adjusting ........... 6-20
C
Cables, checking and lubricating ......... 6-25
Care ........................................................ 7-1
Catalytic converter ................................ 3-18
Clutch lever ........................................... 3-13
Clutch lever free play, adjusting ........... 6-18
Coolant ................................................. 6-11
Coolant temperature warning light ......... 3-2
Cowlings, removing and installing .......... 6-7
D
Data recording, vehicle ........................... 9-3
Diagnostic connectors ............................ 9-2
Dimmer switch ...................................... 3-12
Drive chain, cleaning and lubricating .... 6-25
Drive chain slack................................... 6-23
E
Engine break-in....................................... 5-1
Engine idling speed .............................. 6-13
Engine oil and oil filter element ............... 6-8
Engine overheating ............................... 6-37
Engine serial number .............................. 9-1
Engine trouble warning light ................... 3-3
F
Front and rear brake pads, checking.... 6-21
Front brake lever free play, checking ... 6-19
Front fork, checking .............................. 6-28
Fuel ....................................................... 3-16
Fuel consumption, tips for reducing ....... 5-5
Fuel tank cap ........................................ 3-16
Fuel tank overflow hose ........................ 3-18
Fuses, replacing.................................... 6-31
H
Handlebar switches .............................. 3-12Helmet holder ....................................... 3-20
High beam indicator light ....................... 3-2
Horn switch .......................................... 3-12
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system............... 3-21
Indicator lights and warning lights ......... 3-2
L
License plate light bulb, replacing........ 6-34
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 ................................................... 5-6
Part locations ......................................... 2-1
Pass switch .......................................... 3-12
S
Safety information .................................. 1-1
Seat ...................................................... 3-19
Shifting ................................................... 5-4
Shift light ................................................ 3-3
Shift pedal ............................................ 3-13
Sidestand ............................................. 3-20
Sidestand, checking and lubricating .... 6-27
Spark plug, checking ............................. 6-7
Specifications ......................................... 8-1
Start/Engine stop switch ...................... 3-12
Starting the engine ................................. 5-2
Steering, checking................................ 6-29
Storage ................................................... 7-4
Supporting the motorcycle................... 6-34
Swingarm pivots, lubricating ................ 6-28
T
Tail/brake light ...................................... 6-33
Throttle grip and cable, checking and
lubricating .......................................... 6-26
Throttle grip free play, adjusting........... 6-14
Tires ...................................................... 6-15
Tool kit.................................................... 6-2
Troubleshooting ................................... 6-35
Troubleshooting chart .......................... 6-36
Turn signal indicator light ....................... 3-2
Turn signal light bulb, replacing ........... 6-33
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