engine YAMAHA NMAX 125 2016 Owner's Manual

Periodic maintenance an d a djustment
6-6
6
EAU72790
TIP
 Engine air filter and V-belt air filter
• This model’s engine air filter is equipped with a disposable oil-coated pa- per element, which must not be cleaned with compressed air to avoid
damaging it.
• The engine air filter element needs to be replaced and the V-belt air filter element needs to be serviced more frequently when riding in unusually wet
or dusty areas.
 Hydraulic brake service
• After disassembling the brake master cylinders and calipers, always change the fluid. Regularly check the brake fluid levels and fill the reser-
voirs as required.
• Every two years replace the internal components of the brake master cyl- inders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
27 *Li
ghts, si gnals an d
switches • Check operation.
• Adjust headlight beam.
√√√√√√
NO. ITEM
X 1000 km
CHECK OR
MAINTENANCE JOB
X 1000 mi ODOMETER
READING
ANNUAL CHECK
16121824
0.6 3.5 7 10.5 14
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Periodic maintenance an d a djustment
6-9
6
EAU67161
Checkin g the spark plu g
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic main-
tenance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
To remove the spark plu g
1. Place the vehicle on the center- stand.
2. Remove panels A and B. (See page 6-7.)
3. Remove the spark plug cap.
4. Remove the spark plug as shown, with the spark plug wrench includ-
ed in the owner’s tool kit. To check the spark plu
g
1. Check that the porcelain insulator around the center electrode of the
spark plug is a medium-to-light
tan (the ideal color when the vehi-
cle is ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrodeerosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a wire thickness gauge and, if nec-
essary, adjust the gap to specifi-
cation.
1. Spark plug cap
1. Spark plug wrench
1
1
Specified spark plu g:
NGK/CPR8EA-9
1. Spark plug gap
Spark plu g g ap:
0.8–0.9 mm (0.031–0.035 in)
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Periodic maintenance an d a djustment
6-10
6 To install the spark plu
g
1. Clean the surface of the spark plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tight-
en it to the specified torque.
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.
3. Install the spark plug cap.
TIP
Install the spark plug cap so that it is
positioned as shown in the illustration
and the spark plug lead does not con-
tact any surrounding parts.
4. Install the panels.
EAU66991
Engine oil an d oil strainer
The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil strainer
cleaned at the intervals specified in the
periodic maintenance and lubrication
chart.
To check the en gine oil level
1. Place the vehicle on the center- stand. 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, remove the engine oil filler
cap, wipe the engine oil dipstick
clean, insert it back into the oil filler
hole (without screwing it in), and
then remove it again to check the
oil level. WARNING! The muffler
an d muffler protector become
very hot d uring use. To avoi d
possi ble burns, let the muffler
an d protector cool b efore re-
moving the oil filler cap.
[EWA17810]
TIP
The engine oil should be between the
tip of the dipstick and the maximum
level mark.
Tightenin g torque:
Spark plug: 13 N·m (1.3 kgf·m, 9.4 lb·ft)
1. Spark plug cap
2. Spark plug lead
1
2
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Periodic maintenance an d a djustment
6-11
6
4. If the engine oil is not between the
tip of the dipstick and the maxi-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
5. Insert the dipstick into the oil filler hole, and then tighten the oil filler
cap.
To chan ge the en gine oil an d clean
the oil strainer 1. Start the engine, warm it up for several minutes, and then turn it
off.
2. Place an oil pan under the engine to collect the used oil.
3. Remove the engine oil filler cap and engine oil drain bolts A and B
to drain the oil from the crankcase.
NOTICE: When removin g the
en gine oil d rain bolt B, the O-
rin g, compression sprin g, an d
oil strainer will fall out. Take
care not to lose these parts.
[ECAT1022]
4. Clean the engine oil strainer with solvent, and then check it for dam-
age and replace it if necessary.
5. Install the engine oil strainer, com- pression spring, new O-ring and
engine oil drain bolt B.
TIP
Make sure that the O-ring is properly
seated.
6. Install engine oil drain bolt A andits new gasket, and then tighten
both drain bolts to their specified
torques.
7. Refill with the specified amount of the recommended engine oil, and
then install and tighten the oil filler
cap.
1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Tip of the engine oil dipstick
1
2
3
4
1. Engine oil drain bolt A
2. Gasket
3. Oil strainer
4. Compression spring
5. O-ring
6. Engine oil drain bolt B
Tightenin g torque:
Engine oil drain bolt A: 20 N·m (2.0 kgf·m, 14 lb·ft)
Engine oil drain bolt B:
32 N·m (3.2 kgf·m, 23 lb·ft)
1
3
4
5
6
2
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Periodic maintenance an d a djustment
6-12
6
TIP
Be sure to wipe off spilled oil on any
parts after the engine and exhaust sys-
tem have cooled down.
NOTICE
ECA11621
 In or der to prevent clutch slip-
pa ge (since the en gine oil also
lu bricates the clutch), do not
mix any chemical additives. Do
not use oils with a diesel speci-
fication of “CD” or oils of a hi gh-
er quality than specifie d. In
a ddition, do not use oils la bele d
“ENERGY CONSERVING II” or
hi gher.
 Make sure that no forei gn mate-
rial enters the crankcase.
8. 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.
9. Turn the engine off, and then check the oil level and correct it if
necessary.
10. Reset the oil change tripmeter and oil change indicator “OIL”. (See
page 3-6 for reset procedures.)
EAU20067
Final transmission oil
The final transmission case must be
checked for oil leakage before each
ride. If any leakage is found, have a
Yamaha dealer check and repair the scooter. In addition, the final transmis-
sion oil must be changed as follows at
the intervals specified in the periodic
maintenance and lubrication chart. 1. Start the engine, warm up the final transmission oil by riding the
scooter for several minutes, and
then stop the engine.
2. Place the scooter on the center- stand.
3. Place an oil pan under the final transmission case to collect the
used oil.
4. Remove the final transmission oil filler cap and its O-ring from the fi-
nal transmission case.
5. Remove the final transmission oil drain bolt and its gasket to drain
the oil from the final transmission
case.
Recommen ded en gine oil:
See page 8-1.
Oil quantity: 0.90 L (0.95 US qt, 0.79 Imp.qt)
1. Final transmission oil filler cap
2. O-ring
1
2
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Periodic maintenance an d a djustment
6-13
6
6. Install the final transmission oil
drain bolt and its new gasket, and
then tighten the bolt to the speci-
fied torque.
7. Refill with the specified amount of the recommended final transmis-
sion oil. WARNING! Make sure
that no forei gn material enters
the final transmission case.
Make sure that no oil gets on
the tire or wheel.
[EWA11312]
8. Install the final transmission oil fill- er cap and its new O-ring, and
then tighten the oil filler cap.
9. Check the final transmission case for oil leakage. If oil is leaking,
check for the cause.
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.
EAUN1090To check the coolant level1. Place the vehicle on the center- stand.
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 through
the check window.
TIP
The coolant should be between the
minimum and maximum level marks.
1. Final transmission oil drain bolt
2. Gasket
Tightening torque:
Final transmission oil drain bolt: 20 N·m (2.0 kgf·m, 14 lb·ft)
Recommen ded final transmission
oil: See page 8-1.
Oil quantity: 0.15 L (0.16 US qt, 0.13 Imp.qt)
12
1. Coolant level check window
2. Maximum level mark
3. Minimum level mark
1
2
3
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Periodic maintenance an d a djustment
6-14
6 3. If the coolant is at or below the
minimum level mark, remove the
right floorboard mat by pulling it
up.
4. Remove the coolant reservoir cov- er.
5. Remove the coolant reservoir cap, add coolant to the maximum level
mark, and then install the reservoir
cap. WARNING! Remove only
the coolant reservoir cap. Never
attempt to remove the ra diator
cap when the en gine is hot.
[EWA15162] NOTICE: If coolant is not
availa ble, use d istilled water or
soft tap water instea d. Do not
use har d water or salt water
since it is harmful to the en gine.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possi ble, other- wise the coolin
g system will not
b e protecte d a gainst frost an d
corrosion. If water has b een
a dde d to the coolant, have a
Yamaha dealer check the anti-
freeze content of the coolant as
soon as possi ble, otherwise the
effectiveness of the coolant will
b e red uced.
[ECA10473]
6. Install the coolant reservoir cover.
7. Place the right floorboard mat in
the original position and push it
downward to secure it.
EAU67280To chan ge the coolant
1. Place the vehicle on a level sur- face and let the engine cool if nec-
essary.
2. Remove panels A and B. (See page 6-7.)
3. Remove the radiator cover by re- moving the bolts.
1. Floorboard mat
1. Coolant reservoir cover
1
1
1. Coolant reservoir cap
Coolant reservoir capacity (up to
the maximum level mark):0.25 L (0.26 US qt, 0.22 Imp.qt)
1
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Periodic maintenance an d a djustment
6-16
6 9. Remove the coolant reservoir cap,
and then turn the coolant reservoir
upside down to empty it.
10. After the coolant is completely drained, thoroughly flush the cool-
ing system with clean tap water.
11. Install the coolant reservoir by in- stalling the bolt.
12. Install the coolant drain bolt and its new gasket, and then tighten
the bolt to the specified torque.
13. Install the coolant drain screw and its new O-ring.
14. Pour the recommended coolant into the reservoir to the maximum
level mark, and then install the
coolant reservoir cap.
15. Pour the recommended coolant into the radiator until it is full.
16. Install the radiator cap, start the engine, let it idle for several min-
utes, and then turn it off.
17. Remove the radiator cap to check the coolant level in the radiator. If
necessary, add sufficient coolant until it reaches the top of the radi-
ator, and then install the radiator
cap.
18. Start the engine, and then check the vehicle for coolant leakage. If
coolant is leaking, have a Yamaha
dealer check the cooling system.
19. Install the radiator cover by install- ing the bolts.
20. Install the panels.
Ti ghtenin g torque:
Coolant drain bolt: 10 N·m (1.0 kgf·m, 7.2 lb·ft)
Antifreeze/water mixture ratio: 1:1
Recommen ded antifreeze:
High-quality ethylene glycol anti-
freeze containing corrosion inhibi-
tors for aluminum engines
Coolant quantity: Radiator (including all routes):0.46 L (0.49 US qt, 0.40 Imp.qt)
Coolant reservoir (up to the maxi-
mum level mark): 0.25 L (0.26 US qt, 0.22 Imp.qt)
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Periodic maintenance an d a djustment
6-20
6
EAU21402
Valve clearance
The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU69760
Tires
Tires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
WARNING
EWA10504
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or d eath from loss of
control.  The tire air pressure must be
checked and a djuste d on col d
tires (i.e., when the temperature
of the tires equals the am bient
temperature).
 The tire air pressure must be
a d juste d in accor dance with the
ri din g speed and with the total
wei ght of ri der, passen ger, car-
g o, an d accessories approve d
for this mo del.
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Periodic maintenance an d a djustment
6-40
6
EAU68020
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.
Operate the electric
starter.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug.
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. IgnitionWet
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
plug 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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