2018 YAMAHA MT-125 checking oil

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 .....................................3-14
Brake lever ....................................3-14
Brake pedal ...................................3-15
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-17
Catalytic converter ........................3-18
Rider seat ......................................3-19
Sidestand ......................................3-20
Ignition circuit cut-off system........3-20
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Starting the engine ..........................5-2
Shifting ............................................5-3
Tips for reducing fuel
consumption ................................5-4
Engine break-in ...............................5-4
Parking ............................................5-5
Periodic maintenance and
adjustment........................................6-1
Owner’s tool kit ...............................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4
Removing and installing cowlings ...6-7
Checking the spark plug .................6-8Engine oil and oil filter element ....... 6-9
Coolant ......................................... 6-12
Replacing the air filter element
and cleaning the check hose..... 6-14
Checking the engine idling
speed......................................... 6-14
Adjusting the throttle grip free
play ............................................ 6-15
Valve clearance ............................. 6-16
Tires .............................................. 6-16
Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the front brake lever
free play ..................................... 6-20
Adjusting the brake pedal free
play ............................................ 6-21
Brake light switches ...................... 6-21
Checking the front and rear brake
pads........................................... 6-22
Checking the brake fluid level....... 6-23
Changing the brake fluid............... 6-24
Drive chain slack ........................... 6-24
Cleaning and lubricating the drive
chain .......................................... 6-26
Checking and lubricating the
cables ........................................ 6-26
Checking and lubricating the
throttle grip and cable ............... 6-27
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
brake pedal................................ 6-28
Checking and lubricating the
sidestand ................................... 6-28
Lubricating the swingarm
pivots ......................................... 6-29
Checking the front fork ................. 6-29
Checking the steering ................... 6-30
Checking the wheel bearings ....... 6-30
Battery .......................................... 6-31
Replacing the fuses ...................... 6-32
Replacing the headlight bulb ........ 6-33
Auxiliary lights ............................... 6-35
Tail/brake light .............................. 6-35
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Periodic maintenance and adjustment
6-11
6 8. Remove and replace the oil filter
element and O-ring.
9. Install the oil filter element cover
by installing the bolts, then tight-
ening them to the specified
torque.
TIP
Make sure that the O-ring is properly
seated.
10. Install the engine oil strainer, com-
pression spring, O-ring and the
engine oil drain bolt, and then
tighten it to the specified torque.NOTICE: Before installing the
engine oil drain bolt, do not for-
get to install the O-ring, com-
pression spring, and oil strainer
in position.
[ECA10422]
11. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the oil filler
cap.
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.
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.
1. Bolt
2. Oil filter element cover
1. Oil filter element
2. O-ring
Tightening torques:
Oil filter element cover bolt:
10 N·m (1.0 kgf·m, 7.2 lb·ft)
Tightening torques:
Engine oil drain bolt:
32 N·m (3.2 kgf·m, 23 lb·ft)
Recommended engine oil:
See page 8-1.
Oil quantity:
Without oil filter element replace-
ment:
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)
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Periodic maintenance and adjustment
6-12
613. Turn the engine off, and then
check the oil level and correct it if
necessary.
14. Reset the oil change indicator.
(See page 3-10.)
EAU20071
Coolant
The 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.
EAUM1726To 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.
TIP
The coolant should be between the
minimum and maximum level marks.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
ZAUM1207
FULL
LOW2
3
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Periodic maintenance and adjustment
6-23
6
EAU40262
Checking the brake fluid level
Before riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the top
of the reservoir level. Replenish the
brake fluid if necessary.
Front brake
Rear brake
WARNING
EWA16011
Improper maintenance can result in
loss of braking ability. Observe
these precautions:
Insufficient brake fluid may al-
low air to enter the brake sys-
tem, reducing braking
performance.Clean the filler cap before re-
moving. Use only DOT 4 brake
fluid from a sealed container.
Use only the specified brake flu-
id; otherwise, the rubber seals
may deteriorate, causing leak-
age.
Refill with the same type of
brake fluid. Adding a brake fluid
other than DOT 4 may result in a
harmful chemical reaction.
Be careful that water or dust
does not enter the brake fluid
reservoir when refilling. Water
will significantly lower the boil-
ing point of the fluid and may re-
sult in vapor lock, an
d dirt may
clog the ABS hydraulic unit
valves.
NOTICE
ECA17641
Brake fluid may damage painted
surfaces or plastic parts. Always
clean up spilled fluid immediately.
As the brake pads wear, it is normal for
the brake fluid level to gradually go
down. A low brake fluid level may indi-
cate worn brake pads and/or brake
system leakage; therefore, be sure to
check the brake pads for wear and the
brake system for leakage. If the brake
fluid level goes down suddenly, have a
Yamaha dealer check the cause before
further riding.
1. Minimum level mark
1. Minimum level mark
Specified brake fluid:
DOT 4
ZAUM1209
I
NFOI
NFO
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Periodic maintenance and adjustment
6-24
6
EAU22733
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the oil seals
of the master cylinders and calipers as
well as the brake hoses replaced at the
intervals listed below or whenever they
are damaged or leaking.
Oil seals: Replace every two
years.
Brake hoses: Replace every four
years.
EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAUM3551To check the drive chain slack
1. Place the motorcycle on the side-
stand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
2. Shift the transmission into the
neutral position.
3. Measure the drive chain slack at
the arrow mark on the swingarm
as shown in the illustration.
4. If the drive chain slack is incorrect,
adjust it as follows.
EAU3431ATo adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.
1. Loosen the axle nut and the lock-
nut on each side of the swingarm.
Drive chain slack:
35.0–45.0 mm (1.38–1.77 in)
1. Drive chain slack
ZAUM1233
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Periodic maintenance and adjustment
6-26
6
EAU23026
Cleaning and lubricating the
drive chain
The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.
NOTICE
ECA10584
The drive chain must be lubricated
after washing the motorcycle, riding
in the rain or riding in wet areas.
1. Clean the drive chain with kero-
sene and a small soft brush.
NOTICE: To prevent damaging
the O-rings, do not clean the
drive chain with steam cleaners,
high-pressure washers or inap-
propriate solvents.
[ECA11122]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant. NOTICE: Do not use
engine oil or any other lubri-
cants for the drive chain, as they
may contain substances that
could damage the O-rings.
[ECA11112]EAU23098
Checking and lubricating the
cables
The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubri-
cated if necessary. If a cable is
damaged or does not move smoothly,
have a Yamaha dealer check or re-
place it. WARNING! Damage to the
outer housing of cables may result
in internal rusting and cause inter-
ference with cable movement. Re-
place damaged cables as soon as
possible to prevent unsafe condi-
tions.
[EWA10712]
Recommended lubricant:
Yamaha cable lubricant or other
suitable cable lubricant
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Periodic maintenance and adjustment
6-29
6
EAUM1653
Lubricating the swingarm piv-
ots
The swingarm pivots must be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU23273
Checking the front fork
The condition and operation of the
front fork must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
To check the condition
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion. WARNING! To avoid injury,
securely support the vehicle so
there is no danger of it falling
over.
[EWA10752]
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
NOTICE
ECA10591
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it.
Recommended lubricant:
Lithium-soap-based grease
ZAUM1212
YA M A H A
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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 ....................... 6-14
Auxiliary lights ....................................... 6-35
B
Battery .................................................. 6-31
Brake and clutch levers, checking and
lubricating ........................................... 6-27
Brake fluid, changing ............................ 6-24
Brake fluid level, checking .................... 6-23
Brake lever ............................................ 3-14
Brake light switches.............................. 6-21
Brake pedal........................................... 3-15
Brake pedal, checking and
lubricating ........................................... 6-28
Brake pedal free play, adjusting ........... 6-21
C
Cables, checking and lubricating ......... 6-26
Care ........................................................ 7-1
Catalytic converter ................................ 3-18
Clutch lever ........................................... 3-13
Clutch lever free play, adjusting ........... 6-19
Coolant ................................................. 6-12
Cowlings, removing and installing .......... 6-7
D
Data recording, vehicle ........................... 9-2
Diagnostic connectors ............................ 9-2
Dimmer switch ...................................... 3-12
Drive chain, cleaning and lubricating .... 6-26
Drive chain slack................................... 6-24
E
Engine break-in....................................... 5-4
Engine idling speed, checking .............. 6-14
Engine oil and oil filter element ............... 6-9
Engine stop switch ............................... 3-12
Engine trouble warning light ................... 3-3
F
Front and rear brake pads, checking.... 6-22
Front brake lever free play, checking ... 6-20
Front fork, checking .............................. 6-29
Fuel ....................................................... 3-17
Fuel consumption, tips for reducing ....... 5-4
Fuel level warning light ........................... 3-2
Fuel tank cap ........................................ 3-16
Fuses, replacing.................................... 6-32
H
Handlebar switches .............................. 3-12
Headlight bulb, replacing ...................... 6-33High beam indicator light ....................... 3-2
Horn switch .......................................... 3-12
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system............... 3-20
Indicator lights and warning lights ......... 3-2
Info switch ............................................ 3-12
L
License plate light bulb, replacing........ 6-36
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 ................................................... 5-5
Part locations ......................................... 2-1
Pass switch .......................................... 3-12
R
Rider seat ............................................. 3-19
S
Safety information .................................. 1-1
Shifting ................................................... 5-3
Shift pedal ............................................ 3-14
Sidestand ............................................. 3-20
Sidestand, checking and lubricating .... 6-28
Spark plug, checking ............................. 6-8
Specifications ......................................... 8-1
Starting the engine ................................. 5-2
Start switch .......................................... 3-12
Steering, checking................................ 6-30
Storage ................................................... 7-4
Supporting the motorcycle................... 6-37
Swingarm pivots, lubricating ................ 6-29
T
Tail/brake light ...................................... 6-35
Throttle grip and cable, checking and
lubricating .......................................... 6-27
Throttle grip free play, adjusting........... 6-15
Tires ...................................................... 6-16
Tool kit.................................................... 6-2
Troubleshooting ................................... 6-37
Troubleshooting charts ........................ 6-38
Turn signal indicator light ....................... 3-2
Turn signal light bulb, replacing ........... 6-36
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