warning YAMAHA NMAX 155 2021 Service Manual

Periodic maintenance an d a djustment
9-23
9
EAU40262
Checkin g the brake flui d levelBefore riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the top
of the reservoir level. Replenish the
brake fluid if necessary.
Front brake Rear
brake
WARNING
EWA16011
Improper maintenance can result in
loss of b raking a bility. O bserve
these precautions:  Insufficient brake flui d may al-
low air to enter the brake sys-
tem, re ducin g brakin g
performance.
 Clean the filler cap before re-
movin g. Use only DOT 4 b rake
flui d from a seale d container. 
Use only the specified b rake flu-
i d ; otherwise, the ru bber seals
may deteriorate, causin g leak-
a g e.
 Refill with the same type of
brake flui d. A ddin g a brake flui d
other than DOT 4 may result in a
harmful chemical reaction.
 Be careful that water or dust
d oes not enter the b rake fluid
reservoir when refillin g. Water
will si gnificantly lower the b oil-
in g point of the flui d an d may re-
sult in vapor lock, an d d ir t may
clo g

the ABS hy draulic unit
valves.
NOTICE
ECA17641
Brake flui d may damag e painted
surfaces or plastic parts. Always
clean up spille d flui d imme diately.As the brake pads wear, it is normal for
the brake fluid level to gradually go
down. A low brake fluid level may indi-
cate worn brake pads and/or brake
system leakage; therefore, be sure to
check the brake pads for wear and the
brake system for leakage. If the brake
1. Minimum level mark
1
1. Minimum level markSpecifie d b rake flui d:
DOT 4
1
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Periodic maintenance an d a djustment
9-25
9
EAU23098
Checkin g an d lu bricatin g the
ca blesThe operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubri-
cated if necessary. If a cable is
damaged or does not move smoothly,
have a Yamaha dealer check or re-
place it. WARNING! Dama ge to the
outer housin g of cab les may result
in internal rustin g an d cause inter-
ference with cab le movement. Re-
place damag ed cab les as soon as
possi ble to prevent unsafe con di-
tions.
[EWA10712] EAU49921
Checkin
g an d lu bricatin g the
throttle grip an d cab leThe operation of the throttle grip
should be checked before each ride. In
addition, the cable should be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
chart.
EAU23173
Lubricatin g the front an d rear
b rake leversFront brake lever
Rear brake lever
The pivoting points of the front and rear
brake levers must be lubricated at the
intervals specified in the periodic main-
tenance and lubrication chart.
Recommen ded lu bricant:
Yamaha cable lubricant or other
suitable cable lubricant
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Periodic maintenance an d a djustment
9-26
9
EAU23215
Checkin g an d lu bricatin g the
centerstan d an d si destan dThe operation of the centerstand and
sidestand should be checked before
each ride, and the pivots and metal-to-
metal contact surfaces should be lubri-
cated if necessary.
WARNING
EWA10742
If the centerstan d or si destan d d oes
not move up an d d own smoothly,
have a Yamaha d ealer check or re-
pair it. Otherwise, the centerstan d or
si destan d coul d contact the groun d
an d d istract the operator, resultin g
in a possib le loss of control.
Recommen ded lu bricant:
Silicone grease
Recommen ded lu bricant:
Lithium-soap-based grease
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Periodic maintenance an d a djustment
9-27
9
EAU23273
Checkin g the front forkThe condition and operation of the
front fork must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
To check the con dition
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation 1. Place the vehicle on a level sur- face and hold it in an upright posi-
tion. WARNING! To avoi d injury,
securely support the vehicle so
there is no dan ger of it fallin g
over.
[EWA10752]
2. While applying the front brake, push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
NOTICE
ECA10591
If any d amage is foun d or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it.
EAU45512
Checkin g the steerin gWorn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Place the vehicle on the center- stand. WARNING! To avoi d inju-
ry, securely support the vehicle
so there is no dan ger of it fallin g
over.
[EWA10752]
2. Hold the lower ends of the front fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steer-
ing.
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Periodic maintenance an d a djustment
9-28
9
EAU23292
Checkin g the wheel bearin gsThe front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
EAU50292
BatteryThe battery is located under the seat.
(See page 6-17.)
This model is equipped with a VRLA
(Valve Regulated Lead Acid) battery.
There is no need to check the electro-
lyte or to add distilled water. However,
the battery lead connections need to
be checked and, if necessary, tight-
ened.
WARNING
EWA10761
 Electrolyte is poisonous an d
d an gerous since it contains sul-
furic aci d, which causes severe b
urns. Avoi d any contact with
skin, eyes or clothin g an d al-
ways shiel d your eyes when
workin g near b atteries. In case
of contact, ad minister the fol-
lowin g FIRST AID.
EXTERNAL: Flush with plenty of water.
INTERNAL: Drink lar ge quan-
tities of water or milk an d im-
me diately call a physician.
EYES: Flush with water for 15 minutes an d seek prompt
me dical attention.
 Batteries pro duce explosive hy-
d ro gen gas. Therefore, keep
sparks, flames, ci garettes, etc.,
away from the battery an d pro-
vi de sufficient ventilation when
char gin g it in an enclose d
space.
 KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
To char ge the b attery
Have a Yamaha dealer charge the bat-
tery as soon as possible if it seems to
have discharged. Keep in mind that the
1. Positive battery lead (red)
2. Battery
3. Negative battery lead (black)
3
2
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
9-33
9 10. Close the seat.
EAU60701
Trou
bleshootin gAlthough Yamaha vehicles 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 vehicle re-
quire any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the vehicle prop-
erly.
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 checkin g the fuel system, d o
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot lig hts from water heaters or furnaces. Gasoline or
g
asoline vapors can i gnite or ex-
plod e, causin g severe injury or prop-
erty damag e.
EAU76551
Smart key system trou bleshootin g
Please check the following items when
the smart key system does not work.  Is the smart key turned on? (See
page 3-4.)
 Is the smart key battery dis-
charged? (See page 3-6.)
 Is the smart key battery installed
correctly? (See page 3-6.)
 Is the smart key being used in a lo-
cation with strong radio waves or
other electromagnetic noise? (See
page 3-1.)
 Are you using the smart key that is
registered to the vehicle?
 Is the vehicle battery discharged?
When the vehicle battery is dis-
charged, the smart key system will
not operate. Please have the vehi-
cle battery charged or replaced.
(See page 9-28.)
Tightenin g torque:
Grab bar bolt:
17 N·m (1.7 kgf·m, 13 lb·ft)
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Periodic maintenance an d a djustment
9-34
9
If the smart key system does not work
after checking the above items, have a
Yamaha dealer check the smart key system.
TIPSee Emergency mode on page 9-38
for information on starting the engine
without the smart key.
EAU76843
Stop an d Start System trou ble-
shootin g
If a problem occurs, check the follow-
ing before taking the vehicle to a
Yamaha dealer.
The Stop an d Start System in dicator
lig ht does not come on.
1. Is the main switch turned on?
2. Is the Stop and Start System switch set to “ ”?
3. Was the engine warmed up suffi- ciently after starting?
4. After the engine was warmed up, was the engine left idling for a cer-
tain period of time?
5. Did the vehicle travel at a speed of 10 km/h or higher? Even if the preceding conditions are
met, the Stop and Start System may
not activate in order to preserve bat-
tery power. In this case, continue to
drive the vehicle.
In addition, the Stop and Start System
indicator light does not come on if the
engine trouble warning light is on.
If the Stop and Start System indicator
light still does not come on after you
checked the preceding conditions,
have a Yamaha dealer check the vehi-
cle as soon as possible.
The Stop an
d Start System in dicator
li g ht comes on, b ut the engine does
not stop automatically. 1. Was the vehicle stopped com- pletely?
The engine may not stop automat-
ically until the vehicle is stopped
for a certain period of time. Try
bringing the vehicle to a complete
stop.
2. Is the throttle grip turned? The engine does not stop auto-
matically if the throttle grip is not in
the fully closed position. Turn the throttle grip to the fully
closed position.
If the engine still does not stop auto-
matically after you checked the pre-
ceding conditions, have a Yamaha
dealer check the vehicle as soon as
possible.
After the eng ine was stopped b y the
Stop an d Start System, the en gine
d oes not restart even if the throttle
g rip is turne d.
1. Is the Stop and Start System switch set to “ ”?
If the Stop and Start System
switch is set to “ ” while the Stop
and Start System is activated, the
Stop and Start System will be
turned off.
2. Was the sidestand operated? When the sidestand is lowered,
the Stop and Start System is de-
activated.
3. Was the engine left stopped by the Stop and Start System for a
long period of time?
A
AA
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Periodic maintenance an d a djustment
9-37
9
EAU86420
En gine overheatin g
WARNING
EWAT1041
Do not remove the ra diator cap when the en gine an d ra diator are hot. Scal din g hot flui d an d steam may be
b lown out un der pressure, which coul d cause serious injury. Be sure to wait until the en gine has cooled .
 Place a thick ra g, like a towel, over the ra diator cap, an d then slowly rotate the cap counterclockwise to the
d etent to allow any resi dual pressure to escape. When the hissin g soun d has stoppe d, press d own on the cap
while turnin g it counterclockwise, an d then remove the cap.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
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Motorcycle care and stora ge
10-2
10 chemicals such as, solvents,
g
asoline, rust removers, b rake
flui d, or antifreeze, etc.
Before washin g
1. Park the vehicle out of direct sun- light and allow it to cool. This will
help avoid water spots.
2. Make sure all caps, covers, elec- trical couplers and connectors are
tightly installed.
3. Cover the muffler end with a plas- tic bag and a strong rubber band.
4. Pre-soak stubborn stains like in- sects or bird droppings with a wet
towel for a few minutes.
5. Remove road grime and oil stains with a quality degreasing agent
and a plastic-bristle brush or
sponge. NOTICE: Do not use
d eg reasin g a gent on areas re-
quirin g lu brication such as
seals, gaskets, an d wheel axles.
Follow prod uct instructions.
[ECA26290]
Washing
1. Rinse off any degreaser and spray down the vehicle with a garden
hose. Use only enough pressure
to do the job. Avoid spraying wa-
ter directly into the muffler, instru-
ment panel, air inlet, or other inner
areas such as underseat storage
compartments.
2. Wash the vehicle with a quality au- tomotive-type detergent mixed
with cool water and a soft, clean
towel or sponge. Use an old tooth-
brush or plastic-bristle brush for
hard-to-reach places. NOTICE:
Use col d water if the vehicle has
b een exposed to salt. Warm wa-
ter will increase salt’s corrosive
properties.
[ECA26301]
3. For windshield-equipped vehicles: Clean the windshield with a soft
towel or sponge dampened with
water and a pH neutral detergent.
If necessary, use a high-quality
windshield cleaner or polish for
motorcycles. NOTICE: Never use
any stron g chemicals to clean
the win dshiel d. A dditionally,
some cleanin g compoun ds for plastic may scratch the win
d-
shiel d, so b e sure to test all
cleanin g prod ucts before gen-
eral application.
[ECA26310]
4. Rinse off thoroughly with clean water. Be sure to remove all deter-
gent residues, as they can be
harmful to plastic parts.
After washin g
1. Dry the vehicle with a chamois or absorbent towel, preferably mi-
crofiber terrycloth.
2. For drive chain-equipped models: Dry and then lubricate the drive
chain to prevent rust.
3. Use a chrome polish to shine chrome, aluminum, and stainless
steel parts. Often the thermally in-
duced discoloring of stainless
steel exhaust systems can be re-
moved through polishing.
4. Apply a corrosion protection spray on all metal parts including
chrome or nickel-plated surfaces.
WARNING! Do not apply sili-
cone or oil spray to seats, han d
g rips, ru bber foot peg s or tire
trea ds. Otherwise these parts
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