2015 YAMAHA MT-125 ignition

PERIODIC MAINTENANCE AND ADJUSTMENT
6-40
6
EAU25872
TroubleshootingAlthough Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from waterheaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or prop-
erty damage.U5D7E4E0.book Page 40 Thursday, July 10, 2014 3:01 PM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-41
6
EAUM2443
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 compression.
Supply fuel.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wet
Dry
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.The engine does not start.
Check the battery.
Operate the electric starter.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.The battery is good.
Check the electrolyte and battery
lead connections, and charge the
battery if necessary.The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the compression.
U5D7E4E0.book Page 41 Thursday, July 10, 2014 3:01 PM

SPECIFICATIONS
8-2
8
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)
Chassis:Frame type:
Semi double cradle
Caster angle:
25.00 °
Trail:
89 mm (3.5 in)Front tire:Type:
Tubeless
Size:
100/80-17 M/C 52H(PIRELLI)-
52S(MICHELIN)
Manufacturer/model:
PIRELLI/SPORT DEMON
Manufacturer/model:
MICHELIN/PILOT STREETRear tire:Type:
Tubeless
Size:
130/70-17 M/C 62H(PIRELLI)-
62S(MICHELIN)Manufacturer/model:
PIRELLI/SPORT DEMON
Manufacturer/model:
MICHELIN/PILOT STREET
Loading:Maximum load:
MT125 180 kg (397 lb)
MT125A 178 kg (392 lb)
(Total weight of rider, passenger, cargo
and accessories)Tire air pressure (measured on cold
tires):Loading condition:
0–90 kg (0–198 lb)
Front:
180 kPa (1.80 kgf/cm², 26 psi)
Rear:
200 kPa (2.00 kgf/cm², 29 psi)
Loading condition:
MT125 90–180 kg (198–397 lb)
MT125A 90–178 kg (198–392 lb)
Front:
180 kPa (1.80 kgf/cm², 26 psi)
Rear:
225 kPa (2.25 kgf/cm², 33 psi)Front wheel:Wheel type:
Cast wheel
Rim size:
17xMT2.75Rear wheel:Wheel type:
Cast wheelRim size:
17 x MT3.75
Front brake:Type:
Single disc brake
Operation:
Right hand operation
Specified brake fluid:
DOT 4Rear brake:Type:
Single disc brake
Operation:
Right foot operation
Specified brake fluid:
DOT 4Front suspension:Type:
Telescopic fork
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
130 mm (5.1 in)Rear suspension:Type:
Swingarm (link suspension)
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
114 mm (4.5 in)Electrical system:Ignition system:
TCI
U5D7E4E0.book Page 2 Thursday, July 10, 2014 3:01 PM

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
U5D7E4E0.book Page 3 Thursday, July 10, 2014 3:01 PM

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
U5D7E4E0.book Page 1 Thursday, July 10, 2014 3:01 PM