check engine YAMAHA MT-25 2016 User Guide

For your safety – pre-operation checks
4-1
4
EAU15599
Inspect your vehicle each time you use it to make sure the vehicle is in safe operating 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 breather hose and overflow hose for obstructions, cracks or
damage, and check hose connections.3-13, 3-15
Engine oil• Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage.6-9
Coolant• Check coolant level in reservoir.
• If necessary, add recommended coolant to specified level.
• Check cooling system for leakage.6-12
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.6-19, 6-20
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Operation and important riding points
5-1
5
EAU15952
Read the Owner’s Manual carefully to
become familiar with all controls. If
there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWA10272
Failure to familiarize yourself with
the controls can lead to loss of con-
trol, which could cause an accident
or injury.
EAU62513
TIPThis model is equipped with:
a lean angle sensor to stop the en-
gine in case of a turnover. In this
case, the display will indicate error
code 30, but this is not a malfunc-
tion. Turn the key to “ ” and then
to “ ” to clear the error code.
Failing to do so will prevent the en-
gine from starting even though the
engine will crank when pushing
the start switch.
an engine auto-stop system. The
engine stops automatically if left
idling for 20 minutes. If the engine
stops, simply push the start
switch to restart the engine.
EAUN0680
Starting the engineIn order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.
The transmission is in gear with
the clutch lever pulled and the
sidestand up.
See page 3-20 for more informa-
tion.
1. Turn the key to “ ” and make
sure that the engine stop switch is
set to “ ”.
The engine trouble warning light
should come on for a few sec-
onds, then go off. NOTICE: If the
warning light does not go off,
have a Yamaha dealer check its
electrical circuit.
[ECAT1121]
2. Shift the transmission into the
neutral position. The neutral indi-
cator light should come on. If not,
ask a Yamaha dealer to check the
electrical circuit.
3. Start the engine by pushing the
start switch.
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Operation and important riding points
5-3
5
EAU16811
Tips for reducing fuel con-
sumptionFuel 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).
EAU16842
Engine break-inThere is never a more important period
in the life of your engine than the period
between 0 and 1600 km (1000 mi). For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1600 km (1000 mi). The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that
might result in engine overheating
must be avoided.
EAU17094
0–1000 km (0–600 mi)
Avoid prolonged operation above 7000
r/min. NOTICE: After 1000 km (600
mi) of operation, the engine oil must
be changed and the oil filter car-
tridge or element replaced.
[ECA10303]
1000–1600 km (600–1000 mi)
Avoid prolonged operation above 8400
r/min.1600 km (1000 mi) and beyond
The vehicle can now be operated nor-
mally.
NOTICE
ECA10311
Keep the engine speed out of
the tachometer red zone.
If any engine trouble should oc-
cur during the engine break-in
period, immediately have a
Yamaha dealer check the vehi-
cle.
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Periodic maintenance and adjustment
6-6
6
21*Front fork• Check operation and for oil leak-
age.√√√√
22*Shock absorber as-
sembly• Check operation and shock ab-
sorber for oil leakage.√√√√
23 Engine oil• Change. (See pages 3-4 and 6-9.)√When the oil change indicator flashes
• Check oil level and vehicle for oil
leakage.Every 5000 km (3000 mi)√
24Engine oil filter car-
tridge•Replace.√√√
25*Cooling system• Check coolant level and vehicle
for coolant leakage.√√√√√
• Change coolant. Every 3 years
26*Front and rear
brake switches• Check operation.√√√√√√
27Moving parts and
cables• Lubricate.√√√√√
28*Throttle grip• Check operation.
• Check throttle grip free play, and
adjust if necessary.
• Lubricate cable and grip housing.√√√√√
29*Lights, signals and
switches• Check operation.
• Adjust headlight beam.√√√√√√ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING
ANNUAL
CHECK 1000 km
(600 mi)10000 km
(6000 mi)20000 km
(12000 mi)30000 km
(18000 mi)40000 km
(24000 mi)
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Periodic maintenance and adjustment
6-8
6
EAU19643
Checking the spark plugsThe spark plugs are important engine
components, which should be
checked periodically, preferably by a
Yamaha dealer. Since heat and depos-
its will cause any spark plug to slowly
erode, they should be removed and
checked in accordance with the peri-
odic maintenance and lubrication
chart. In addition, the condition of the
spark plugs can reveal the condition of
the engine.
The porcelain insulator around the
center electrode of each spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally), and all spark plugs installed
in the engine should have the same
color. If any spark plug shows a dis-
tinctly different color, the engine could
be operating improperly. Do not at-
tempt to diagnose such problems
yourself. Instead, have a Yamaha deal-
er check the vehicle.
If a spark plug shows signs of elec-
trode erosion and excessive carbon or
other deposits, it should be replaced.Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the spark
plug threads.
TIPIf a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4…
1/2 turn past finger tight. However, the
spark plug should be tightened to the
specified torque as soon as possible.
Specified spark plug:
NGK/CR9E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Tightening torque:
Spark plug:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
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Periodic maintenance and adjustment
6-9
6
EAUN1150
Engine oil and oil filter car-
tridgeThe engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter car-
tridge replaced at the intervals speci-
fied in the periodic maintenance and
lubrication chart.
To check the engine oil level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion. A slight tilt to the side can
result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, and then check the oil level
through the engine oil level check
window located at the bottom-
right side of the crankcase.TIPThe engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
To change the engine oil (with or
without oil filter cartridge replace-
ment)
1. Place the vehicle on a level sur-
face.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Place an oil pan under the engine
to collect the used oil.4. Remove the cowling by removing
the bolts.
5. Remove the engine oil filler cap,
the engine oil drain bolt and its
gasket to drain the oil from the
crankcase.1. Engine oil filler cap
2. Engine oil level check window
3. Maximum level mark
4. Minimum level mark
3
4
1 2
1. Cowling
2. Bolt
1. Engine oil drain bolt
2. Gasket
1
2
12
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Periodic maintenance and adjustment
6-11
6
10. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the oil filler
cap.
TIPBe sure to wipe off spilled oil on any
parts after the engine and exhaust sys-
tem have cooled down.NOTICE
ECA11621
In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives. Do
not use oils with a diesel speci-
fication of “CD” or oils of a high-
er quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.
Make sure that no foreign mate-
rial enters the crankcase.11. Install the cowling by installing the
bolts.
12. Start the engine, and then let it idle
for several minutes while checking
it for oil leakage. If oil is leaking,
immediately turn the engine off
and check for the cause.
TIPAfter the engine is started, the engine
oil pressure warning light should go off.NOTICE
ECA20860
If the oil pressure warning light flick-
ers or remains on even if the oil level
is correct, immediately turn the en-
gine off and have a Yamaha dealer
check the vehicle.13. Turn the engine off, wait a few
minutes until the oil settles, and
then check the oil level and cor-
rect it if necessary.
1. Engine oil drain bolt
2. GasketTightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended engine oil:
See page 8-1.
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)
2
1
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Periodic maintenance and adjustment
6-12
6
EAU20071
CoolantThe coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU38176
To check the coolant level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.TIPThe coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.2. Check the coolant level in the
coolant reservoir.TIPThe coolant should be between the
minimum and maximum level marks.
3. If the coolant is at or below the
minimum level mark, remove the
coolant reservoir cover by remov-
ing the bolts, remove the coolant
reservoir cap, and then add cool-
ant to the maximum level mark.
WARNING! Remove only the
coolant reservoir cap. Never at-
tempt to remove the radiator
cap when the engine is hot.
[EWA15162]
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 insteadof 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]
1. Maximum level mark
2. Minimum level mark
3. Coolant reservoir
1
2
3
1. Bolt
2. Coolant reservoir cover
2
1
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Periodic maintenance and adjustment
6-13
6
4. Install the reservoir cap, and then
install the coolant reservoir cover
by installing the bolts.
EAU33032
Changing the coolant
The coolant must be changed at the in-
tervals specified in the periodic main-
tenance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove
the radiator cap when the engine is
hot.
[EWA10382]EAUN1172
Replacing the air filter ele-
ment and cleaning the check
hoseThe air filter element should be re-
placed at the intervals specified in the
periodic maintenance and lubrication
chart. Replace the air filter element
more frequently if you are riding in un-
usually wet or dusty areas. In addition,
the air filter check hose must be fre-
quently checked and cleaned if neces-
sary.
To replace the air filter element
1. Remove the rider seat. (See page
3-16.)
2. Remove the left side panel bolts.3. Remove the left side panel by re-
moving the lower projection on the
panel from the slot, and then re-
moving the upper projection as
shown.
1. Coolant reservoir capCoolant reservoir capacity (up to
the maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
1
1. Left side panel
2. Bolt
1. Projection
1
2
1
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Periodic maintenance and adjustment
6-14
6 4. Lift up the rubber covers, and then
remove the air filter case cover by
removing the screws.
5. Pull the air filter element out.6. Insert a new air filter element into
the air filter case. NOTICE: Make
sure that the air filter element is
properly seated in the air filter
case. The engine should never
be operated without the air filter
element installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively worn.
[ECA10482]
7. Install the air filter case cover by
installing the screws, and then
place the rubber covers in their
original positions.
8. Place the left side panel in the
original position, and then install
the bolts.
9. Install the rider seat.
To clean the air filter check hose
1. Check the hose on the front of the
air filter case for accumulated dirt
or water.2. If dirt or water is visible, remove
the hose, clean it, and then install
it.
1. Air filter case cover
2. Screw
3. Rubber cover
1. Air filter element
12
23
1
1. Air filter check hose
1
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