engine coolant YAMAHA NMAX 155 2021 Owners Manual

Table of contentsSafety information ............................ 1-1
Further safe-riding points ............... 1-5
Description ....................................... 2-1
Left view ......................................... 2-1
Right view ....................................... 2-2
Controls and instruments ............... 2-3
Smart key system ........................... 3-1
Smart key system ........................... 3-1
Operating range of the smart key system .................................. 3-2
Handling of the smart key and mechanical keys ......................... 3-3
Smart key ....................................... 3-4
Replacing the smart key battery..... 3-6
Main switch .................................... 3-7
Stop an d Start System ..................... 4-1
Stop and Start System ................... 4-1
Stop and Start System operation ... 4-1
Special features .............................. 5-1
CCU (Communication Control Unit) ................................ 5-1
Instrument an d control functions ... 6-1
Indicator lights and warning lights............................................ 6-1
Multi-function meter unit ................ 6-3
Handlebar switches ...................... 6-10 Front brake lever ........................... 6-11
Rear brake lever ............................ 6-11
ABS ............................................... 6-12
Traction control system ................ 6-13
Fuel tank cap ................................ 6-14
Fuel ............................................... 6-15
Fuel tank overflow hose ................ 6-17
Catalytic converter ........................ 6-17
Seat ............................................... 6-17
Helmet holders .............................. 6-18
Storage compartments ................. 6-19
Adjusting the shock absorber
assemblies ................................. 6-20
Power outlet ................................. 6-21
Sidestand ...................................... 6-22
Ignition circuit cut-off system ....... 6-22
For your safety – pre-operation
checks ............................................... 7-1
Operation an d important ri din g
points ................................................. 8-1
Engine break-in ............................... 8-1
Starting the engine .......................... 8-2
Starting off ...................................... 8-2
Acceleration and deceleration ........ 8-3
Braking ............................................ 8-3
Tips for reducing fuel consumption ................................ 8-3
Parking ........................................... 8-4 Perio
dic maintenance an d
a d justment ........................................ 9-1
Tool kit ............................................ 9-1
Periodic maintenance chart for the emission control system ....... 9-2
General maintenance and lubrication chart .......................... 9-3
Removing and installing panels ...... 9-7
Checking the spark plug................. 9-9
Canister ........................................ 9-11
Engine oil and oil strainer ............. 9-11
Why Yamalube.............................. 9-13
Final transmission oil .................... 9-13
Coolant ......................................... 9-15
Air filter and V-belt case
air filter elements ....................... 9-16
Checking the throttle grip
free play..................................... 9-19
Valve clearance............................. 9-19
Tires .............................................. 9-19
Cast wheels .................................. 9-21
Checking the front and rear brake lever free play .................. 9-21
Checking the front and rear brake pads ................................ 9-22
Checking the brake fluid level ...... 9-23
Changing the brake fluid .............. 9-24
Checking the V-belt ...................... 9-24
Checking and lubricating the
cables ........................................ 9-25UBBDE0E0.book Page 1 Wednesday, June 2, 2021 2:57 PM

Description
2-2
2
EAU10421
Right view
1
10 9 8 7 623 4 5
1. Tail/brake light
2. Battery (page 9-28)
3. Storage compartment B (page 6-19)
4. Fuse box (page 9-29)
5. Headlight (page 9-31)
6. Coolant reservoir (page 9-15)
7. Spark plug (page 9-9)
8. Engine oil drain bolt A (page 9-11)
9. Engine oil drain bolt B (page 9-11)
10.Engine oil filler cap (page 9-11)
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Instrument and control functions
6-5
6
EAUN2920
Clock
The clock uses a 12-hour time system.
To set the clock1. Push the “MENU” switch until the
hour digits start flashing.
2. Use the “MENU” switch to set the hours.
3. Push the “MENU” switch until the minute digits start flashing.
4. Use the “MENU” switch to set the minutes.
5. Push the “MENU” switch until the minute digits stop flashing. The
setting is confirmed.
TIPWhen CCU and smartphone is con-
nected after vehicle power on, the
clock is automatically adjusted.
EAU86860
Coolant temperature meter
This meter shows the temperature of
the coolant, and thereby the condition
of the engine. The segments come on
from “C” (cold) to “H” (hot) as the en-
gine temperature increases. If the hot
segment flashes, stop the engine as
soon as possible, and let the engine
cool. (See page 9-37.)
TIPIf a problem is detected in the electrical
circuit, all segments will flash repeat-
edly. Have a Yamaha dealer check the
vehicle.
EAU86870
VVA in dicator
This model is equipped with variable
valve actuation (VVA) for good fuel
economy and acceleration in both the
low-speed and high-speed ranges.
The VVA indicator comes on when the
variable valve actuation system has
switched to the high-speed range.
To turn the VVA indicator on or off1. Turn the vehicle off.
1. Clock
1
1. Coolant temperature meter
1
1. VVA (variable valve actuation) indicator
1
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For your safety – pre-operation checks
7-1
7
EAU1559B
Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always follow the inspection
and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility of an acci dent or equipment d amage.
Do not operate the vehicle if you fin d any pro blem. If a pro blem cannot be corrected b y the proce dures provi ded in
this manual, have the vehicle inspecte d b y a Yamaha dealer.Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel • Check fuel level in fuel tank.
• Refuel if necessary.
• Check fuel line for leakage.
• Check fuel tank overflow hose for obstructions, cracks or damage, and check
hose connection. 6-15, 6-17
En gine oil • Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage. 9-11
Final transmission oil • Check vehicle for oil leakage. 9-13
Coolant • Check coolant level in reservoir.
• If necessary, add recommended coolant to specified level.
• Check cooling system for leakage. 9-15
Front brake • Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage. 9-21, 9-22, 9-23
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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
9-15
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
9-37
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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Specifications
11-1
11
Dimensions:Overall length:1935 mm (76.2 in)
Overall width:
740 mm (29.1 in)
Overall height: 1160 mm (45.7 in)
Seat height: 765 mm (30.1 in)
Wheelbase:
1340 mm (52.8 in)
Ground clearance: 125 mm (4.92 in)
Minimum turning radius: 2.0 m (6.56 ft)Wei ght:Curb weight:
131 kg (289 lb)Engine:Combustion cycle:
4-stroke
Cooling system: Liquid cooled
Valve train: SOHC
Number of cylinders:
Single cylinder
Displacement: 155 cm3
Bore  stroke:
58.0  58.7 mm (2.28  2.31 in)
Starting system:
Electric starter
Engine oil:Recommended brand:
SAE viscosity grades:
10W-40
Recommended engine oil grade: API service SG type or higher, JASO
standard MA or MB
Engine oil quantity: Oil change:0.90 L (0.95 US qt, 0.79 Imp.qt)Final transmission oil:Type:
Motor oil SAE 10W-40 type SG or higher
Quantity: 0.10 L (0.11 US qt, 0.09 Imp.qt)Coolant quantity:Coolant reservoir (up to the maximum level
mark):0.13 L (0.14 US qt, 0.11 Imp.qt)
Radiator (including all routes):
0.46 L (0.49 US qt, 0.40 Imp.qt)Fuel:Recommended fuel:Unleaded gasoline (E10 acceptable)
Octane number (RON):
90
Fuel tank capacity: 7.1 L (1.9 US gal, 1.6 Imp.gal)
Fuel reserve amount: 1.7 L (0.45 US gal, 0.37 Imp.gal)
Fuel injection:Throttle body:ID mark:B2T1Front tire:Type:
Tubeless
Size: 110/70-13M/C 48P
Manufacturer/model: DUNLOP/SCOOT SMART LRear tire:Type: Tubeless
Size: 130/70-13M/C 63P
Manufacturer/model:
DUNLOP/SCOOT SMART LLoa din g:Maximum load:
167 kg (368 lb)
(Total weight of rider, passenger, cargo and
accessories)Front brake:Type:
Hydraulic single disc brakeRear brake:Type:
Hydraulic single disc brakeFront suspension:Type:
Telescopic fork
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13-1
13
IndexAABS ....................................................... 6-12
ABS warning light ................................... 6-2
Acceleration and deceleration ................ 8-3
Activating the Stop and Start System .... 4-1
Air filter and V-belt case air filter
elements ............................................. 9-16
App Connect icon ................................... 6-4BBattery .................................................. 9-28
Brake fluid, changing ............................ 9-24
Brake fluid level, checking .................... 9-23
Brake lever, front .................................. 6-11
Brake lever, rear.................................... 6-11
Brake levers, lubricating ....................... 9-25
Braking.................................................... 8-3CCables, checking and lubricating ......... 9-25
Canister................................................. 9-11
Care ...................................................... 10-1
Catalytic converter ................................ 6-17
CCU (Communication Control Unit) ....... 5-1
Centerstand and sidestand, checking and lubricating .................... 9-26
Clock....................................................... 6-5
Coolant ................................................. 9-15
Coolant temperature meter .................... 6-5DData recording, vehicle ......................... 12-2
Diagnostic connector............................ 12-2
Dimmer switch ...................................... 6-10
Display units, switching .......................... 6-4EEmergency mode.................................. 9-38 Engine break-in ...................................... 8-1
Engine oil and oil strainer ..................... 9-11
Engine overheating ............................... 9-37
Engine serial number ............................ 12-1
FFinal transmission oil ............................ 9-13
Front and rear brake lever free play,
checking............................................. 9-21
Front and rear brake pads, checking ... 9-22
Front fork, checking ............................. 9-27
Fuel ....................................................... 6-15
Fuel consumption, tips for reducing ...... 8-3
Fuel meter .............................................. 6-4
Fuel tank cap ........................................ 6-14
Fuel tank overflow hose ....................... 6-17
Fuses, replacing ................................... 9-29HHandlebar switches .............................. 6-10
Hazard switch....................................... 6-10
Helmet holders ..................................... 6-18
High beam indicator light ....................... 6-1
Horn switch .......................................... 6-10IIdentification numbers .......................... 12-1
Ignition circuit cut-off system ............... 6-22
Incoming call indicator light ................... 6-3
Incoming notification indicator light ....... 6-3
Indicator lights and warning lights ......... 6-1KKey, handling of smart and mechanical keys................................... 3-3MMain switch ............................................ 3-7
Maintenance and lubrication, periodic ... 9-3 Maintenance,
emission control system .......................9-2
Malfunction indicator light (MIL)..............6-1
Matte color, caution ..............................10-1
Menu switch..........................................6-11
Model label ...........................................12-1
Multi-function display .............................6-6
Multi-function meter unit .........................6-3
OOperating range of the smart key system ..................................................3-2PPanels, removing and installing ..............9-7
Parking ....................................................8-4
Part locations ..........................................2-1
Power outlet ..........................................6-21
Precautions when using the Stop and Start System .........................4-3SSafe-riding points....................................1-5
Safety information ...................................1-1
Seat .......................................................6-17
Shock absorber assemblies,
adjusting .............................................6-20
Sidestand ..............................................6-22
Smart key ................................................3-4
Smart key battery, replacing ...................3-6
Smart key system ...................................3-1
Smart key system indicator light.............6-2
Smart key system, troubleshooting ......9-33
Smartphone battery level meter..............6-4
Spark plug, checking ..............................9-9
Special features ......................................5-1
Specifications .......................................11-1
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