2015 YAMAHA MT-125 engine

MOTORCYCLE CARE AND STORAGE7-1
7
EAU37834
Matte color cautionNOTICE
ECA15193
Some models are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
advice on what products to use be-
fore cleaning the vehicle. Using a
brush, harsh chemical products or
cleaning compounds when cleaning
these parts will scratch or damage
their surface. Wax also should not
be applied to any matte colored fin-
ished parts.
EAUM2453
CareWhile the open design of a motorcycle
reveals the attractiveness of the tech-
nology, it also makes it more vulnera-
ble. Rust and corrosion can develop
even if high-quality components are
used. A rusty exhaust pipe may go un-
noticed on a car, however, it detracts
from the overall appearance of a mo-
torcycle. Frequent and proper care
does not only comply with the terms of
the warranty, but it will also keep your
motorcycle looking good, extend its
life and optimize its performance.
Before cleaning
1. Cover the muffler outlet with a
plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov-
ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt,
like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such prod-ucts onto seals, gaskets, sprock-
ets, the drive chain and wheel
axles. Always rinse the dirt and
degreaser off with water.
Cleaning
NOTICE
ECA10773
Avoid using strong acidic wheel
cleaners, especially on spoked
wheels. If such products are
used on hard-to-remove dirt, do
not leave the cleaner on the af-
fected area any longer than in-
structed. Also, thoroughly rinse
the area off with water, immedi-
ately dry it, and then apply a cor-
rosion protection spray.
Improper cleaning can damage
plastic parts (such as cowlings,
panels, windshields, headlight
lenses, meter lenses, etc.) and
the mufflers. Use only a soft,
clean cloth or sponge with wa-
ter to clean plastic. However, if
the plastic parts cannot be thor-
oughly cleaned with water, di-
luted mild detergent with water
may be used. Be sure to rinse
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MOTORCYCLE CARE AND STORAGE
7-2
7off any detergent residue using
plenty of water, as it is harmful
to plastic parts.
Do not use any harsh chemical
products on plastic parts. Be
sure to avoid using cloths or
sponges which have been in
contact with strong or abrasive
cleaning products, solvent or
thinner, fuel (gasoline), rust re-
movers or inhibitors, brake fluid,
antifreeze or electrolyte.
Do not use high-pressure wash-
ers or steam-jet cleaners since
they cause water seepage and
deterioration in the following ar-
eas: seals (of wheel and swing-
arm bearings, fork and brakes),
electric components (couplers,
connectors, instruments,
switches and lights), breather
hoses and vents.
For motorcycles equipped with
a windshield: Do not use strong
cleaners or hard sponges as
they will cause dulling or
scratching. Some cleaning
compounds for plastic may
leave scratches on the wind-shield. Test the product on a
small hidden part of the wind-
shield to make sure that it does
not leave any marks. If the wind-
shield is scratched, use a quality
plastic polishing compound af-
ter washing.
After normal useRemove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottlebrush
for hard-to-reach areas. Stubborn dirt
and insects will come off more easily if
the area is covered with a wet cloth for
a few minutes before cleaning. Use the
special sponge, which is located under
the tool kit, to clean the muffler and to
remove any discoloration from it.
After riding in the rain, near the sea oron salt-sprayed roadsSince sea salt or salt sprayed on roads
during winter are extremely corrosive
in combination with water, carry out
the following steps after each ride in
the rain, near the sea or on salt-
sprayed roads.
TIPSalt sprayed on roads in the winter
may remain well into spring.1. Clean the motorcycle with cold
water and a mild detergent, after
the engine has cooled down.
NOTICE: Do not use warm wa-
ter since it increases the corro-
sive action of the salt.
[ECA10792]
2. After drying the motorcycle, apply
a corrosion protection spray on all
metal, including chrome- and
nickel-plated, surfaces to prevent
corrosion.
After cleaning
1. Dry the motorcycle with a chamois
or an absorbing cloth.
2. Immediately dry the drive chain
and lubricate it to prevent it from
rusting.
3. Use a chrome polish to shine
chrome, aluminum and stainless-
steel parts, including the exhaust
system. (Even the thermally in-
duced discoloring of stainless-
steel exhaust systems can be re-
moved through polishing.)
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MOTORCYCLE CARE AND STORAGE7-3
7 4. To prevent corrosion, it is recom-
mended to apply a corrosion pro-
tection spray on all metal,
including chrome- and nickel-plat-
ed, surfaces.
5. Use spray oil as a universal clean-
er to remove any remaining dirt.
6. Touch up minor paint damage
caused by stones, etc.
7. Wax all painted surfaces.
8. Let the motorcycle dry completely
before storing or covering it.
WARNING
EWA11132
Contaminants on the brakes or tires
can cause loss of control.
Make sure that there is no oil or
wax on the brakes or tires.
If necessary, clean the brake
discs and brake linings with a
regular brake disc cleaner or
acetone, and wash the tires with
warm water and a mild deter-
gent. Before riding at higher
speeds, test the motorcycle’s
braking performance and cor-
nering behavior.
NOTICE
ECA10801
Apply spray oil and wax spar-
ingly and make sure to wipe off
any excess.
Never apply oil or wax to any
rubber and plastic parts, but
treat them with a suitable care
product.
Avoid using abrasive polishing
compounds as they will wear
away the paint.TIPConsult a Yamaha dealer for ad-
vice on what products to use.
Washing, rainy weather or humid
climates can cause the headlight
lens to fog. Turning the headlight
on for a short period of time will
help remove the moisture from the
lens.
EAU43203
StorageShort-term
Always store your motorcycle in a cool,
dry place and, if necessary, protect it
against dust with a porous cover. Be
sure the engine and the exhaust sys-
tem are cool before covering the mo-
torcycle.NOTICE
ECA10811
Storing the motorcycle in a
poorly ventilated room or cover-
ing it with a tarp, while it is still
wet, will allow water and humid-
ity 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
Before storing your motorcycle for sev-
eral months:
1. Follow all the instructions in the
“Care” section of this chapter.
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MOTORCYCLE CARE AND STORAGE
7-4
72. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
3. Perform the following steps to
protect the cylinder, piston rings,
etc. from corrosion.
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.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap. WARNING! To
prevent damage or injury
from sparking, make sure to
ground the spark plug elec-
trodes while turning the en-
gine over.
[EWA10952]
4. Lubricate all control cables and
the pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.
5. Check and, if necessary, correct
the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
6. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
7. Remove the battery and fully
charge it. Store it in a cool, dry
place and charge it once a month.
Do not store the battery in an ex-
cessively cold or warm place [less
than 0 °C (30 °F) or more than 30
°C (90 °F)]. For more information
on storing the battery, see page
6-30.TIPMake any necessary repairs before
storing the motorcycle.
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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:
MT125 138 kg (304 lb)
MT125A 140 kg (309 lb)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-50
Recommended 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 10Spark plug(s):Manufacturer/model:
NGK/CR9E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction ratio:
73/24 (3.042)
Final drive:
Chain
Secondary reduction ratio:
48/14 (3.429)
Transmission type:
Constant mesh 6-speed
Operation:
Left foot operation
Gear ratio:
1st:
34/12 (2.833)
–20 –10 0
1020 30 40 50 C 10 30 50 70 90 110 0 130 F
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
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SPECIFICATIONS
8-3
8
Charging system:
AC magnetoBattery:Model:
12N5.5-4A / YUASA
Voltage, capacity:
12 V, 5.5 AhHeadlight:Bulb type:
Halogen bulbBulb voltage, wattage × quantity:Headlight:
12 V, 55.0 W/60.0 W × 1
Tail/brake light:
LED
Front turn signal light:
12 V, 10.0 W × 2
Rear turn signal light:
12 V, 10.0 W × 2
Auxiliary light:
LED
License plate light:
12 V, 5.0 W × 1
Meter lighting:
LED
Neutral indicator light:
LED
High beam indicator light:
LED
Turn signal indicator light:
LED
Fuel level warning light:
LEDEngine trouble warning light:
LED
ABS warning light:
MT125A LED
Fuses:Main fuse:
20.0 A
Headlight fuse:
15.0 A
Signaling system fuse:
7.5 A
Ignition fuse:
7.5 A
Radiator fan motor fuse:
5.0 A
ABS control unit fuse:
MT125A 10.0 A
ABS motor fuse:
MT125A 30.0 A
ABS solenoid fuse:
MT125A 20.0 A
Backup fuse:
10.0 A
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10-1
10
INDEX
AABS (for ABS models) .......................... 3-14
ABS warning light (for ABS models) ....... 3-3
Air filter element and check hose,
replacing and cleaning ....................... 6-14
Auxiliary light ........................................ 6-34BBattery .................................................. 6-30
Brake and clutch levers, checking and
lubricating........................................... 6-26
Brake fluid, changing............................ 6-23
Brake fluid level, checking.................... 6-22
Brake lever............................................ 3-13
Brake light switches ............................. 6-21
Brake pedal .......................................... 3-14
Brake pedal, checking and
lubricating........................................... 6-27
Brake pedal free play, adjusting ........... 6-20CCables, checking and lubricating ......... 6-26
Care ........................................................ 7-1
Catalytic converter ............................... 3-17
Clutch lever........................................... 3-13
Clutch lever free play, adjusting ........... 6-19
Coolant ................................................. 6-13
Cowlings, removing and installing.......... 6-8DDimmer switch...................................... 3-12
Drive chain, cleaning and lubricating ... 6-25
Drive chain slack .................................. 6-24EEngine break-in ...................................... 5-3
Engine idling speed, checking.............. 6-15
Engine oil and oil filter element............. 6-10Engine stop switch............................... 3-12
Engine trouble warning light .................. 3-3
FFront and rear brake pads, checking ... 6-21
Front brake lever free play, checking ... 6-20
Front fork, checking ............................. 6-28
Fuel ...................................................... 3-16
Fuel consumption, tips for reducing ...... 5-3
Fuel level warning light........................... 3-2
Fuel tank cap........................................ 3-15
Fuses, replacing ................................... 6-31HHandlebar switches ............................. 3-11
Headlight bulb, replacing ..................... 6-33
High beam indicator light ....................... 3-2
Horn switch .......................................... 3-12IIdentification numbers ........................... 9-1
Ignition circuit cut-off system .............. 3-19
Indicator lights and warning lights ......... 3-2
Info switch ............................................ 3-12LLicense plate light bulb, replacing ....... 6-35MMain 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 ........................ 3-4NNeutral indicator light ............................. 3-2
PParking.................................................... 5-4
Part locations.......................................... 2-1
Pass switch........................................... 3-12RRider seat.............................................. 3-18SSafety information................................... 1-1
Shifting.................................................... 5-2
Shift pedal............................................. 3-13
Sidestand.............................................. 3-18
Sidestand, checking and lubricating .... 6-27
Spark plug, checking .............................. 6-9
Specifications ......................................... 8-1
Starting the engine ................................. 5-1
Start switch ........................................... 3-12
Steering, checking ................................ 6-29
Storage ................................................... 7-3
Supporting the motorcycle ................... 6-36
Swingarm pivots, lubricating ................ 6-28TTail/brake light ...................................... 6-34
Throttle grip and cable, checking and
lubricating ........................................... 6-26
Throttle grip free play, adjusting ........... 6-15
Tires ...................................................... 6-16
Tool kit .................................................... 6-2
Troubleshooting .................................... 6-40
Troubleshooting charts ......................... 6-41
Turn signal indicator light ....................... 3-2
Turn signal light bulb, replacing............ 6-35
Turn signal switch ................................. 3-12VValve clearance..................................... 6-16
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