fuel YAMAHA MT-125 2020 User Guide

Instrument and control functions
3-18
3
EAU58301
Fuel tank overflow hose
Before operating the vehicle:
Check the fuel tank overflow hose
connection and routing.
Check the fuel tank overflow hose
for cracks or damage, and replace
it if necessary.
Make sure that the fuel tank over-
flow hose is not blocked, and
clean it if necessary.
EAU13435
Catalytic converter
The exhaust system contains catalytic
converter(s) to reduce harmful exhaust
emissions.
WARNING
EWA10863
The exhaust system is hot after op-
eration. To prevent a fire hazard or
burns:
Do not park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.
Park the vehicle in a place
where pedestrians or children
are not likely to touch the hot
exhaust system.
Make sure that the exhaust sys-
tem has cooled down before
doing any maintenance work.
Do not allow the engine to idle
more than a few minutes. Long
idling can cause a build-up of
heat.
1. Fuel tank overflow hose
1
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For your safety – pre-operation checks
4-1
4
EAU63441
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.
• Check fuel tank overflow hose for obstructions, cracks
or damage, and check hose connection.3-16,
3-18
Engine oil• Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage.6-8
Coolant• Check coolant level in reservoir.
• If necessary, add recommended coolant to specified
level.
• Check cooling system for leakage.6-11
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.6-21,
6-22
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.6-21,
6-22
Clutch• Check operation.
• Lubricate cable if necessary.
• Check lever free play.
• Adjust if necessary.6-18
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Operation and important riding points
5-5
5 The neutral indicator light should
come on and then the clutch lever
can be released.
WARNING
EWA17380
Improper braking can cause
loss of control or traction. Al-
ways use both brakes and apply
them smoothly.
Make sure that the motorcycle
and the engine have sufficiently
slowed before shifting to a low-
er gear. Engaging a lower gear
when the vehicle or engine
speed is too high could make
the rear wheel lose traction or
the engine to over-rev. This
could cause loss of control, an
accident and injury. It could also
cause engine or drive train dam-
age.
EAU16811
Tips for reducing fuel con-
sumption
Fuel 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).
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Operation and important riding points
5-6
5
EAU17214
Parking
When parking, stop the engine, and
then remove the key from the main
switch.
WARNING
EWA10312
Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely to
touch them and be burned.
Do not park on a slope or on soft
ground, otherwise the vehicle
may overturn, increasing the
risk of a fuel leak and fire.
Do not park near grass or other
flammable materials which
might catch fire.
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Periodic maintenance and adjustment
6-3
6
EAU71021
TIP
The annual checks must be performed every year, except if a distance-
based maintenance is performed instead.
From 30000 km (17500 mi), repeat the maintenance intervals starting from
6000 km (3500 mi).
Items marked with an asterisk should be performed by a Yamaha dealer as
they require special tools, data and technical skills.
EAU71060
Periodic maintenance chart for the emission control system
NO. ITEM
1*Fuel line• Check fuel hoses for cracks or
damage.
• Replace if necessary.√√√√√
2*Spark plug• Check condition.
• Adjust gap and clean.√√
• Replace.√√
3*Valve clearance• Check and adjust.√√√√
4*Fuel injection• Check and adjust engine idle
speed.√√√√√√
5*Exhaust system• Check for leakage.
• Tighten if necessary.
• Replace gasket if necessary.√√√√√X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 mi
ODOMETER
READING
ANNUAL CHECK
16121824
0.63.5710.514
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Periodic maintenance and adjustment
6-15
6
EAU21403
Valve clearance
The valves are an important engine
component, and since valve clearance
changes with use, they must be
checked and adjusted at the intervals
specified in the periodic maintenance
chart. Unadjusted valves can result in
improper air-fuel mixture, engine
noise, and eventually engine damage.
To prevent this from occurring, have
your Yamaha dealer check and adjust
the valve clearance at regular intervals.
TIP
This service must be performed when
the engine is cold.
EAU77621
Tires
Tires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
WARNING
EWA10504
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.
The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).
The tire air pressure must be
adjusted in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approved
for this model.
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Periodic maintenance and adjustment
6-35
6
EAU25872
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from water
heaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or prop-
erty damage.
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Periodic maintenance and adjustment
6-36
6
EAU86390
Troubleshooting chart
1. FuelThere is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine turns over
quickly.
The engine turns over
slowly.
Try starting the
engine.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug(s).
Check the battery
lead connections,
and charge the
battery if necessary.
2. BatteryThe battery is good.
The engine does not
start.
Check the ignition.
3. IgnitionWet
Dry
There is compression.
There is no
compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
Operate the electric
starter.
Try starting the
engine.
Check the fuel level
in the fuel tank.
4. Compression
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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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