2016 YAMAHA MT-25 Owners Manual

Periodic maintenance and adjustment
6-38
6
EAU42505
Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Remove the spark plugs
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gaps, or replace the spark plugs.
Have a Yamaha dealer check the vehicle.
Operate the electric starter.4. Compression
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.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The engine does not start.
Check the ignition.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
DryWet
Operate the electric starter.
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Periodic maintenance and adjustment
6-39
6Engine 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 rotate the cap counterclockwise 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.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
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Motorcycle care and storage
7-1
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.
EAU54661
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 caps, 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.
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. Apply a corrosion protection spray
on all metal, including chrome-
and nickel-plated, surfaces to pre-
vent corrosion.
Cleaning the windshieldAvoid using any alkaline or strong acid
cleaner, gasoline, brake fluid, or any
other solvent. Clean the windshield
with a cloth or sponge dampened with
a mild detergent, and then wash it off
thoroughly with water. For additional
cleaning, use Yamaha Windshield
Cleaner or another high-quality wind-
shield cleaner. Some cleaning com-
pounds for plastics may leave
scratches on the windshield. Before
using such cleaners, test an area of the
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Motorcycle care and storage
7-3
7 windshield which does not affect your
visibility and which cannot be easily
recognized.
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.)
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.
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Motorcycle care and storage
7-4
7
EAU26183
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.2. 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 cylinders, piston rings,
etc. from corrosion.
a. Remove the spark plug caps
and spark plugs.
b. Pour a teaspoonful of engine
oil into each spark plug bore.
c. Install the spark plug caps onto
the spark plugs, and then
place the spark plugs on the
cylinder head so that the elec-
trodes are grounded. (This will
limit sparking during the next
step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder walls 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 caps
from the spark plugs, and then
install the spark plugs and the
spark plug caps.
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
6-28.
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Motorcycle care and storage
7-5
7
TIPMake any necessary repairs before
storing the motorcycle.
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Specifications
8-1
8
Dimensions:Overall length:
2090 mm (82.3 in)
Overall width:
745 mm (29.3 in)
Overall height:
1035 mm (40.7 in)
Seat height:
780 mm (30.7 in)
Wheelbase:
1380 mm (54.3 in)
Ground clearance:
160 mm (6.30 in)
Minimum turning radius:
2.7 m (8.86 ft)Weight:Curb weight:
165 kg (364 lb)Engine:Combustion cycle:
4-stroke
Cooling system:
Liquid cooled
Valve train:
DOHC
Cylinder arrangement:
Inline
Number of cylinders:
2-cylinder
Displacement:
250 cm3
Bore × stroke:
60.0 × 44.1 mm (2.36 × 1.74 in)Compression ratio:
11.6 : 1
Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:Recommended brand:
YAMALUBE
SAE viscosity grades:
10W-40
Recommended engine oil grade:
API service SG type or higher, JASO
standard MA
Engine oil quantity:
Oil change:
1.80 L (1.90 US qt, 1.58 Imp.qt)
With oil filter removal:
2.10 L (2.22 US qt, 1.85 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):
0.96 L (1.01 US qt, 0.84 Imp.qt)Air filter:Air filter element:
Oil-coated paper elementFuel:Recommended fuel:
Regular unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity:
14 L (3.7 US gal, 3.1 Imp.gal)Fuel reserve amount:
3.0 L (0.79 US gal, 0.66 Imp.gal)
Fuel injection:Throttle body:
ID mark:
1WD1 00Spark plug(s):Manufacturer/model:
NGK/CR9E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)Clutch:Clutch type:
Wet, multiple-discDrivetrain:Primary reduction ratio:
3.043 (70/23)
Final drive:
Chain
Secondary reduction ratio:
3.071 (43/14)
Transmission type:
Constant mesh 6-speed
Gear ratio:
1st:
2.667 (40/15)
2nd:
1.882 (32/17)
3rd:
1.455 (32/22)
4th:
1.200 (30/25)
5th:
1.037 (28/27)
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