light YAMAHA NMAX 155 2021 Owner's Manual

Instrument and control functions
6-15
6
To install the fuel tank cap, turn it
clockwise until the “ ” mark is facing
forward. Close the fuel tank cap lid.
WARNING
EWA10132
Make sure that the fuel tank cap is
properly installed
before ri din g.
Leakin g fuel is a fire hazar d.
EAU13213
FuelMake sure there is sufficient gasoline in
the tank.
WARNING
EWA10882
Gasoline an d gasoline vapors are
extremely flammab le. To avoid fires
an d explosions an d to re duce the
risk of injury when refueling , follow
these instructions.1. Before refueling, turn off the en- gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. Stop filling when the fuel reaches the
bottom of the filler tube. Because
fuel expands when it heats up,
heat from the engine or the sun
can cause fuel to spill out of the
fuel tank. 3. Wipe up any spilled fuel immedi-
ately. NOTICE: Immediately
wipe off spille d fuel with a clean,
d ry, soft cloth, since fuel may
d eteriorate painte d surfaces or
plastic parts.
[ECA10072]
4. Be sure to securely close the fuel tank cap.
WARNING
EWA15152
Gasoline is poisonous an d can
cause injury or death. Han dle gaso-
line with care. Never siphon gasoline
b y mouth. If you shoul d swallow
some gasoline or inhale a lot of g as-
oline vapor, or get some gasoline in
your eyes, see your doctor imme di-
1. “ ” mark
2. Fuel tank cap
1 2
1. Fuel tank filler tube
2. Maximum fuel level
1
2
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Operation and important ri din g points
8-2
8
EAU86741
Startin g the en gineThe ignition circuit cut-off system will
enable starting only when the side-
stand is up.
To start the engine1. Turn the main switch on.
2. Confirm the indicator and warning light(s) come on for a few sec-
onds, and then go off. (See page
6-1.)TIPDo not start the engine if the en-
gine trouble warning light remains
on.
 The ABS warning light should
come on and stay on until the ve-
hicle reaches a speed of 10 km/h
(6 mi/h).NOTICE
ECA24110
If a warnin g or in dicator li ght does
not work as d escribed a bove, have a
Yamaha dealer check the vehicle.3. Close the throttle completely.
4. While applying the front or rear
brake, push the start switch. 5. Release the start switch when the
engine starts, or after 5 seconds.
Wait 10 seconds before pressing
the switch again to allow battery
voltage to restore.
NOTICE
ECA11043
For maximum en gine life, never ac-
celerate har d when the en gine is
col d!
EAU45093
Startin g off1. While pulling the rear brake lever
with your left hand and holding the
grab bar with your right hand,
push the scooter off the center-
stand.
2. Sit astride the seat, and then ad- just the rear view mirrors.
3. Switch the turn signals on.
4. Check for oncoming traffic, and then slowly turn the throttle grip
(on the right) in order to take off.
5. Switch the turn signals off.1. Grab bar
1
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Operation and important rid ing points
8-3
8
EAU16782
Acceleration an d d ecelerationThe speed can be adjusted by opening
and closing the throttle. To increase
the speed, turn the throttle grip in di-
rection (a). To reduce the speed, turn
the throttle grip in direction (b).
EAU60650
Brakin g
WARNING
EWA17790
Avoi d b rakin g har d or su ddenly
(especially when leanin g over to
one si de), otherwise the vehicle
may skid or overturn.
 Railroa d crossin gs, streetcar
rails, iron plates on road con-
struction sites, an d manhole
covers become extremely slip-
pery when wet. Therefore, slow
d own when approachin g such
areas an d cross them with cau-
tion.
 Keep in min d that b raking on a
wet road is much more difficult.
 Ride slowly d own a hill, as brak-
in g d ownhill can be very d iffi-
cult.1. Close the throttle completely.
2. Apply both front and rear brakes simultaneously while gradually in-
creasing the pressure.
EAU16821
Tips for re ducin g fuel con-
sumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
 Avoid high engine speeds during
acceleration.
 Avoid high engine speeds with no
load on the engine.
 Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at traf-
fic lights or at railroad crossings).
(b)
(a)
ZAUM0199
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Periodic maintenance an d a djustment
9-5
9
20 En gine oil • Change (warm engine before
draining).
• Check oil level and vehicle for oil leakage. At the initial interval and when the oil change indicator flashes or
comes on. 
21 *Engine oil strainer • Clean. 
22 *Final transmission
oil • Check vehicle for oil leakage.

• Change. 
23 *Coolin g system • Check coolant level and vehicle
for coolant leakage. 
• Change. Every 3 years
24 *V-belt • Replace. When the V-belt replacement indicator flashes or comes on
25 *Front an
d rear
b rake switches • Check operation.

26 *Movin
g parts an d
cab les • Lubricate.

27 *Throttle
grip hous-
in g an d cab le • Check operation and free play.
• Adjust the throttle cable free play
if necessary.
• Lubricate the throttle grip housing and cable. 
28 *Li
ghts, si gnals an d
switches • Check operation.
• Adjust headlight beam.

NO. ITEM CHECK OR MAINTENANCE JOB
ODOMETER READING
ANNUAL
CHECK
1000 km
(600 mi) 6000 km
(3500 mi) 12000 km
(7000 mi) 1
8000 km

(10500 mi) 24000 km
(14000 mi)
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Periodic maintenance an d a djustment
9-9
9 2. Install the windshield by installing
the screws.
EAU67161
Checkin g the spark plu gThe 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 9-7.)
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).
TIPIf 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.
1. Spark plug cap
1
1. Spark plug wrench
1
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Periodic maintenance an d a djustment
9-11
9
EAU36113
CanisterThis model is equipped with a canister
to prevent the discharging of fuel vapor
into the atmosphere. Before operating
this vehicle, make sure to check the
following:
 Check each hose connection.
 Check each hose and canister for
cracks or damage. Replace if
damaged.
 Make sure that the canister
breather is not blocked, and if
necessary, clean it.
EAU66995
Engine oil an d oil strainerThe 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 fill-
er 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 before re-
movin g the oil filler cap.
[EWA17810]
TIPThe engine oil should be between the
tip of the dipstick and the maximum
level mark.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.
1. Canister
2. Canister breather
2
1
1. Oil filler hole
2. O-ring
3. Engine oil dipstick
4. Maximum level mark
5. Tip of the engine oil dipstick
3245
1
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Periodic maintenance an d a djustment
9-15
9
EAU20071
CoolantThe 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.
EAUN2930
To check the coolant level
1. 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 in the
coolant reservoir.TIPThe coolant should be between the
minimum and maximum level marks.
3. If the coolant is at or below theminimum 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 been
1. Maximum level mark
2. Minimum level mark
1. Floorboard mat
1
2
1
1. Coolant reservoir cover
1
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Periodic maintenance an d a djustment
9-30
9
If a fuse is blown, replace it as follows. 1. Turn off the electrical circuit in question, and then turn off the
main switch.
2. Remove the panel C. (See page 9-7.) 3. Remove the blown fuse, and then
install a new fuse of the specified
amperage. WARNING! Do not
use a fuse of a hi gher ampera ge
ratin g than recommen ded to
avoi d causin g extensive dam-
a g e to the electrical system an d
possi bly a fire.
[EWA15132]
4. Turn the main switch on, and then
turn on the electrical circuit in
question to check if the device op-
erates.TIPIf the fuse immediately blows again,
have a Yamaha dealer check the elec-
trical system.5. Install the panel C. (See page 9-7.)
1. Signaling system fuse
2. Terminal fuse 1
3. Smart key system fuse
4. ABS motor fuse
5. ABS solenoid fuse
6. Spare fuse
7. Fuel injection system fuse
8. Backup fuse
9. Main fuse
10.Ignition fuse
11.Headlight fuse
12.ABS control unit fuse1
6
2
3
4
5
7
8
9
11
12
610
Specified
fuses:
Main fuse: 30.0 A
Terminal fuse 1:
5.0 A
Headlight fuse: 7.5 A
Signaling system fuse: 7.5 A
Ignition fuse:
7.5 A
Smart key system fuse: 2.0 A
ABS motor fuse: 30.0 A
Fuel injection system fuse:
7.5 A
ABS solenoid fuse: 15.0 A
ABS control unit fuse: 2.0 A
Backup fuse:
7.5 A
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Periodic maintenance an d a djustment
9-31
9
EAUN2261
Vehicle li ghtsThis model is equipped with LED lights
for headlights, auxiliary lights and
brake/tail light. If a light does not come
on, check the fuse and then have a
Yamaha dealer check the vehicle.NOTICE
ECA16581
Do not affix any type of tinted film or
stickers to the head light lens.
EAU43054
Replacin g a front turn si gnal
li g ht bul b1. Place the vehicle on the center-
stand.
2. Remove the turn signal light bulb socket (together with the bulb) by
turning it counterclockwise.
3. Remove the burnt-out bulb by pulling it out. 4. Insert a new bulb into the socket.
5. Install the socket (together with
the bulb) by turning it clockwise.
1. Headlight (high beam)
2. Headlight (low beam)
3. Auxiliary light
2
3
1
1. Turn signal light bulb socket
1
1. Turn signal light bulb
1
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Periodic maintenance an d a djustment
9-32
9
EAU67320
Replacin g a rear turn si gnal
lig ht bul b1. Open the seat. (See page 6-17.)
2. Remove the grab bar by removing
the bolts.
3. Remove the taillight cover by re- moving the screws. 4. Remove the turn signal light bulb
socket (together with the bulb) by
turning it counterclockwise.
5. Remove the burnt-out bulb by pulling it out. 6. Insert a new bulb into the socket.
7. Install the socket (together with
the bulb) by turning it clockwise.
8. Install the taillight cover by install- ing the screws.
9. Install the grab bar by installing the bolts, and then tightening them to
the specified torque.1. Grab bar
2. Bolt1
2
1. Taillight cover
2. Screw
1. Turn signal light bulb socket1 2
1
1. Turn signal light bulb
1
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