2018 YAMAHA MT-03 spark plugs

Table of contents
Safety information ............................1-1
Description ........................................2-1
Left view ..........................................2-1
Right view........................................2-2
Controls and instruments ................2-3
Instrument an d 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.......................3-11
Clutch lever ...................................3-12
Shift pedal .....................................3-13
Brake lever ....................................3-13
Brake pedal ...................................3-14
ABS ...............................................3-14
Fuel tank cap.................................3-15
Fuel................................................3-16
Fuel tank overflow hose ................3-17
Catalytic converter ........................3-18
Seats .............................................3-18
Helmet holders ..............................3-20
Storage compartment ...................3-21
Adjusting the shock absorber assembly ....................3-21
Luggage strap holders ..................3-22
Sidestand ......................................3-23
Ignition circuit cut-off system........3-23
For your safety – pre-
operation checks ..............................4-1
Operation an d important
ri din g points ......................................5-1
Starting the engine ..........................5-2
Shifting ............................................5-3
Engine break-in ...............................5-4
Parking ............................................5-4
Perio dic maintenance
an d a djustment .................................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
Checking the spark plugs ............... 6-7
Canister........................................... 6-8
Engine oil and oil filter cartridge ..... 6-8
Coolant ......................................... 6-11
Replacing the air filter element and cleaning the check hose..... 6-13
Checking the throttle grip free play.............................. 6-14
Valve clearance ............................. 6-15
Tires .............................................. 6-15
Cast wheels .................................. 6-17
Adjusting the clutch
lever free play ............................ 6-18
Checking the brake lever free play ............................ 6-19
Brake light switches ...................... 6-19
Checking the front and rear brake pads ......................... 6-20
Checking the brake fluid level....... 6-21
Changing the brake fluid............... 6-22
Drive chain slack ........................... 6-22
Cleaning and lubricating the drive chain ........................... 6-24
Checking and lubricating
the cables .................................. 6-24
Checking and lubricating the throttle grip and cable ......... 6-25
Checking and lubricating the brake and shift pedals ............... 6-25
Checking and lubricating the
brake and clutch levers ............. 6-26
Checking and lubricating the sidestand ............................. 6-26
Lubricating the swingarm pivots ........................ 6-27
Checking the front fork ................. 6-27
Checking the steering ................... 6-28
Checking the wheel bearings ....... 6-28
Battery .......................................... 6-29
Replacing the fuses ...................... 6-30
Replacing the headlight bulb ........ 6-32
Auxiliary light ................................. 6-33
Tail/brake light .............................. 6-33
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Periodic maintenance an d a djustment
6-7
6
EAU19643
Checkin g the spark plu gs
The 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.
TIP
If 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 plu g:
NGK/LMAR8A-9
1. Spark plug gap
Spark plu g g ap:
0.8–0.9 mm (0.031–0.035 in)
Ti ghtenin g torque:
Spark plug: 13 N·m (1.3 kgf·m, 9.6 lb·ft)
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Periodic maintenance an d a djustment
6-37
6
EAU63470
Trou bleshootin g charts
Startin g pro blems or poor en gine performance
1. FuelThere is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine turns over
quickly.
The engine turns over
slowly.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gaps, or
replace the spark
plugs.
Check the battery
lead connections, and
have a Yamaha dealer
charge the battery if
necessary.
2. BatteryThe battery is good.
The engine does not
start.
Check the ignition.
3. IgnitionWetOperate the electric
starter.
Dry
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.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plugs and check
the electrodes.
Operate the electric
starter.
Operate the electric
starter.
Check the fuel level
in the fuel tank.
4. Compression
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Motorcycle care and stora ge
7-4
7 on for a short period of time will
help remove the moisture from the
lens.
EAU26183
Stora
ge
Short-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
z Storin g the motorcycle in a
poorly ventilated room or cover-
in g it with a tarp, while it is still
wet, will allow water an d humi d-
ity to seep in an d cause rust.
z To prevent corrosion, avoi d
d amp cellars, sta bles ( because
of the presence of ammonia)
an d areas where stron g chemi-
cals are store d.
Lon g-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
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Motorcycle care and stora ge
7-5
7
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-
a g e or injury from sparkin g,
make sure to groun d the
spark plu g electro des while
turnin g the en gine 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
6-29.
TIP
Make any necessary repairs before
storing the motorcycle.
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10-1
10
Index
A
ABS ....................................................... 3-14
ABS warning light ................................... 3-3
Air filter element and check hose,
replacing and cleaning ....................... 6-13
Auxiliary light......................................... 6-33
B
Battery .................................................. 6-29
Brake and clutch levers, checking
and lubricating .................................... 6-26
Brake and shift pedals, checking and lubricating .................................... 6-25
Brake fluid, changing ............................ 6-22
Brake fluid level, checking .................... 6-21
Brake lever ............................................ 3-13
Brake lever free play, checking............. 6-19
Brake light switches.............................. 6-19
Brake pedal........................................... 3-14
C
Cables, checking and lubricating ......... 6-24
Canister................................................... 6-8
Care ........................................................ 7-1
Catalytic converter ................................ 3-18
Clutch lever ........................................... 3-12
Clutch lever free play, adjusting ........... 6-18
Coolant ................................................. 6-11
D
Data recording, vehicle ........................... 9-3
Diagnostic connector.............................. 9-2
Dimmer switch ...................................... 3-11
Drive chain, cleaning and lubricating .... 6-24
Drive chain slack................................... 6-22
E
Engine break-in....................................... 5-4
Engine oil and oil filter cartridge ............. 6-8
Engine serial number .............................. 9-1
Engine stop switch ............................... 3-12
Engine trouble warning light ................... 3-3
F
Front and rear brake pads, checking.... 6-20
Front fork, checking .............................. 6-27
Fuel ....................................................... 3-16
Fuel tank cap ........................................ 3-15
Fuel tank overflow hose ........................ 3-17
Fuses, replacing.................................... 6-30
H
Handlebar switches .............................. 3-11
Headlight bulb, replacing ...................... 6-32
Helmet holders...................................... 3-20
High beam indicator light........................ 3-2 Horn switch .......................................... 3-12
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system............... 3-23
Indicator lights and warning lights ......... 3-2
L
License plate light bulb, replacing........ 6-34
Luggage strap holders ......................... 3-22
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
O
Oil pressure warning light ....................... 3-2
P
Parking ................................................... 5-4
Part locations ......................................... 2-1
Pass switch .......................................... 3-11
S
Safety information .................................. 1-1
Seats .................................................... 3-18
Shifting ................................................... 5-3
Shift pedal ............................................ 3-13
Shift timing indicator light....................... 3-4
Shock absorber assembly, adjusting............................................. 3-21
Sidestand ............................................. 3-23
Sidestand, checking and lubricating .... 6-26
Spark plugs, checking ............................ 6-7
Specifications ......................................... 8-1
Starting the engine ................................. 5-2
Start switch .......................................... 3-12
Steering, checking................................ 6-28
Storage ................................................... 7-4
Storage compartment .......................... 3-21
Supporting the motorcycle................... 6-35
Swingarm pivots, lubricating ................ 6-27
T
Tail/brake light ...................................... 6-33
Throttle grip and cable, checking and lubricating .................... 6-25
Throttle grip free play, checking........... 6-14
Tires ...................................................... 6-15
Tool kit.................................................... 6-2
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