YAMAHA NMAX 155 2021 Manual Online

Periodic maintenance an d a djustment
9-18
9
TIPIf dirt or water was found in the check
hose, be sure to check the V-belt case
air filter element for excessive dirt or
damage and clean or replace it if nec-
essary.Cleanin g the V- belt case air filter el-
ement 1. Place the vehicle on the center- stand.
2. Remove the screws, and then pull the V-belt case air filter element
cover outward and away from the
V-belt case. 3. Pull the V-belt case air filter ele-
ment out, and then clean it with
solvent. After cleaning, remove
the remaining solvent by squeez-
ing the element. WARNING! Use
only a ded icated parts cleanin g
solvent. To avoi d the risk of fire
or explosion, do not use gaso-
line or solvents with a low flash
point.
[EWA10432]
NOTICE: To avoi d
d amag ing the air filter element,
han dle it g ently an d carefully,
an d d o not twist it.
[ECA10522]
4. Apply oil of the recommended
type to the entire surface of the
sponge material, and then
squeeze the excess oil out.TIPThe air filter element should be
wet but not dripping.
 Check the air filter element for ex-
cessive dirt or damage and re-
place it if necessary.5. Insert the element into the V-belt
case.
6. Install the air filter element cover by installing the screws.
1. V-belt case air filter element cover
2. Screw
2
1
2
1. V-belt case air filter element
1
Recommen ded oil:
Yamaha foam air filter oil or other
quality foam air filter oil
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Periodic maintenance an d a djustment
9-19
9
EAU21386
Checkin g the throttle grip free
playMeasure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, have a Yamaha
dealer adjust it.
EAU21403
Valve clearanceThe valves are an important engine
component, and since valve clearance
changes with use, they must be
checked and adjusted at the intervals
specified in the periodic maintenance
chart. Unadjusted valves can result in
improper air-fuel mixture, engine
noise, and eventually engine damage.
To prevent this from occurring, have
your Yamaha dealer check and adjust
the valve clearance at regular intervals.TIPThis service must be performed when
the engine is cold.
EAU69761
TiresTires 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 death 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
1. Throttle grip free playThrottle g rip free play:
3.0–5.0 mm (0.12–0.20 in)
1
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Periodic maintenance an d a djustment
9-20
9
wei
ght of ri der, passen ger, car-
g o, an d accessories approve d
for this mo del.
WARNING
EWA10512
Never overload your vehicle. Opera-
tion of an overloa ded vehicle coul d
cause an acci dent.
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail
or glass fragments in it, or if the side-
wall is cracked, have a Yamaha dealer
replace the tire immediately.TIPThe tire tread depth limits may differ
from country to country. Always com-
ply with the local regulations.
WARNING
EWA10472
 Have a Yamaha dealer replace
excessively worn tires. Besi des
b ein g ille gal, operatin g the vehi-
cle with excessively worn tires
d ecreases ri din g sta bility an d
can lead to loss of control.
 The replacement of all wheel
and b rake-relate d parts, inclu d-
in g the tires, shoul d b e left to a
Yamaha dealer, who has the
necessary professional knowl-
e dg e an d experience to d o so.
 Ride at mo derate spee ds after
chan gin g a tire since the tire
surface must first b e “broken
in” for it to d evelop its optimal
characteristics.Tire information
This model is equipped with tubeless
tires and rubber tire air valves.
Tires age, even if they have not been
used or have only been used occasion-
ally. Cracking of the tread and sidewall
rubber, sometimes accompanied by
carcass deformation, is an evidence of
Col d tire air pressure:
1 person: Front: 150 kPa (1.50 kgf/cm2, 22 psi)
Rear: 250 kPa (2.50 kgf/cm2, 36 psi)
2 persons:
Front: 150 kPa (1.50 kgf/cm2, 22 psi)
Rear:
250 kPa (2.50 kgf/cm2, 36 psi)
Maximum loa d:
Veh ic le:
167 kg (368 lb)
The vehicle’s maximum load is the
combined weight of the rider, pas-
senger, cargo, and any accessories.
1. Tire sidewall
2. Tire wear indicator
3. Tire tread depth
Minimum tire trea d d epth (front an d
rear):
1.6 mm (0.06 in)
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Periodic maintenance an d a djustment
9-21
9 ageing. Old and aged tires shall be
checked by tire specialists to ascertain
their suitability for further use.
WARNING
EWA10462
The front an
d rear tires shoul d b e of
the same make an d d esi gn, other-
wise the han dlin g characteristics of
the vehicle may b e different, which
coul d lea d to an acci dent.After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha.
EAU21963
Cast wheelsTo maximize the performance, durabil-
ity, and safe operation of your vehicle,
note the following points regarding the
specified wheels.
 The wheel rims should be
checked for cracks, bends, warp-
age or other damage before each
ride. If any damage is found, have
a Yamaha dealer replace the
wheel. Do not attempt even the
smallest repair to the wheel. A de-
formed or cracked wheel must be
replaced.
 The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.
EAU50861
Checkin g the front an d rear
b rake lever free playFront
Rear
Front tire:
Size:110/70-13M/C 48P
Manufacturer/model: DUNLOP/SCOOT SMART L
Rear tire:
Size:130/70-13M/C 63P
Manufacturer/model:
DUNLOP/SCOOT SMART L
1. No brake lever free play
1. No brake lever free play
1
1
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Periodic maintenance an d a djustment
9-22
9
There should be no free play at the
brake lever ends. If there is free play,
have a Yamaha dealer inspect the
brake system.
WARNING
EWA14212
A soft or spon
gy feelin g in the brake
lever can in dicate the presence of
air in the hy draulic system. If there is
air in the hy draulic system, have a
Yamaha dealer blee d the system be-
fore operatin g the vehicle. Air in the
hy draulic system will diminish the
b rakin g performance, which may re-
sult in loss of control an d an acci-
d ent.
EAU22393
Checkin g the front an d rear
b rake pa dsThe front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22434
Front brake pad s
Each front brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear indicator grooves have almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU22461
Rear
brake pa ds
Each rear brake pad is provided with a
wear indicator, which allows you to
check the brake pad wear without hav-
ing to disassemble the brake. To check
the brake pad wear, check the position
of the wear indicator while applying the
brake. If a brake pad has worn to the
point that the wear indicator almost
touches the brake disc, have a
Yamaha dealer replace the brake pads
as a set.
1. Brake pad wear indicator groove
1 1
1. Brake pad wear indicator
1
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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
9-24
9
fluid level goes down suddenly, have a
Yamaha dealer check the cause before further riding.
EAU22734
Chan gin g the brake flui dHave a Yamaha dealer change the
brake fluid every 2 years. In addition,
have the seals of the master cylinders
and brake calipers, as well as the brake
hoses replaced at the intervals listed
below or sooner if they are damaged or
leaking.
 Brake seals: every 2 years
 Brake hoses: every 4 years
EAUU0311
Checkin g the V- beltThe V-belt must be checked and re-
placed by a Yamaha dealer at the inter-
vals specified in the periodic
maintenance and lubrication chart.
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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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