2018 YAMAHA MT-125 air filter

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
6-4
6
EAU71361
General maintenance and lubrication chart
NO. ITEM
1*Diagnostic system
check• Perform dynamic inspection us-
ing Yamaha diagnostic tool.
• Check the error codes.√√√√√√
2*Air filter element• Clean.√√
• Replace.√√
3Air filter case
check hose• Clean.√√√√√
4*Battery• Check electrolyte level and spe-
cific gravity.
• Make sure that the breather
hose is properly routed.√√√√√
5Clutch• Check operation.
•Adjust.√√√√√
6*Front brake• Check operation, fluid level, and
for fluid leakage.
• Replace brake pads if neces-
sary.√√√√√√
7*Rear brake• Check operation, fluid level, and
for fluid leakage.
• Replace brake pads if neces-
sary.√√√√√√
8*Brake hoses• Check for cracks or damage.√√√√√
• Replace. Every 4 years
9*Brake fluid• Change. Every 2 years
10*Wheels• Check runout and for damage.
• Replace if necessary.√√√√
11*Tires• Check tread depth and for dam-
age.
• Replace if necessary.
• Check air pressure.
• Correct if necessary.√√√√√
12*Wheel bearings• Check bearing for looseness or
damage.√√√√X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READINGANNUAL CHECK
1 6 12 18 24
0.6 3.5 7 10.5 14
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Periodic maintenance and adjustment
6-6
6
EAU72740
TIP
The air filter needs more frequent service if you are riding in unusually wet or
dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
25 Engine oil• Change (warm engine before
draining).At the initial interval and when
the oil change indicator flashes
or comes on
• Check oil level and vehicle for oil
leakage.Every 3000 km (1800 mi)
26Engine oil filter el-
ement• Replace.√√√
27*Cooling system• Check coolant level and vehicle
for coolant leakage.√√√√√
• Change. Every 3 years
28*Front and rear
brake switches• Check operation.√√√√√√
29*Moving parts and
cables• Lubricate.√√√√√
30*Throttle grip hous-
ing and cable• Check operation and free play.
• Adjust the throttle cable free
play if necessary.
• Lubricate the throttle grip hous-
ing and cable.√√√√√
31*Lights, signals and
switches• Check operation.
• Adjust headlight beam.√√√√√√ NO. ITEM
X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READING
ANNUAL CHECK
16121824
0.6 3.5 7 10.5 14
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Periodic maintenance and adjustment
6-14
6
EAUM2391
Replacing the air filter ele-
ment and cleaning the check
hose
The air filter element should be re-
placed at the intervals specified in the
periodic maintenance and lubrication
chart. Have a Yamaha dealer replace
the air filter element more frequently if
you are riding in unusually wet or dusty
areas. In addition, the air filter check
hose must be frequently checked and
cleaned if necessary.
To clean the air filter check hose
1. Check the hose on the side 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.
EAU44735
Checking the engine idling
speed
Check the engine idling speed and, if
necessary, have it corrected by a
Yamaha dealer.
1. Air filter check hose
Engine idling speed:
1350–1550 r/min
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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:
2.5 m (8.20 ft)
Weight:
Curb weight:
141 kg (311 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-40
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:
BR61 00
Spark plug(s):
Manufacturer/model:
NGK/CR9E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Clutch:
Clutch type:
Wet, multiple-disc
Drivetrain:
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)
2nd:
30/16 (1.875)
3rd:
30/22 (1.364)
4th:
24/21 (1.143)
5th:
22/23 (0.957)
6th:
21/25 (0.840)
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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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