torque YAMAHA NMAX 155 2021 Owners Manual

Periodic maintenance an d a djustment
9-1
9
EAU17246
Periodic inspection, adjustment, and
lubrication will keep your vehicle in the
safest and most efficient condition
possible. Safety is an obligation of the
vehicle owner/operator. The most im-
portant points of vehicle inspection,
adjustment, and lubrication are ex-
plained on the following pages.
The intervals given in the periodic
maintenance charts should be simply
considered as a general guide under
normal riding conditions. However, de-
pending on the weather, terrain, geo-
graphical location, and individual use,
the maintenance intervals may need to
be shortened.
WARNING
EWA10322
Failure to properly maintain the vehi-
cle or performin g maintenance ac-
tivities incorrectly may increase
your risk of injury or death durin g
service or while usin g the vehicle. If
you are not familiar with vehicle ser-
vice, have a Yamaha d ealer perform
service.
WARNING
EWA15123
Turn off the en gine when performin g
maintenance unless otherwise
specified .
 A runnin g en gine has movin g
parts that can catch on body
parts or clothin g an d electrical
parts that can cause shocks or
fires.
 Runnin g the en gine while ser-
vicin g can lead to eye injury,
b urns, fire, or car bon monoxi de
poisonin g – possi bly lea din g to
d eath. See pag e 1-3 for more in-
formation a bout car bon monox-
i d e.
WARNING
EWA15461
Brake discs, calipers, drums, and
linin gs can b ecome very hot d uring
use. To avoi d possi ble burns, let
b rake components cool before
touchin g them.
EAU85230
Tool kitThe tool kit is in the location shown.
The information included in this manual
and the tools provided in the tool kit are
intended to assist you in the perfor-
mance of preventive maintenance and
minor repairs. However, a torque
wrench and other tools are necessary
to perform certain maintenance work
correctly.TIPIf you do not have the tools or experi-
ence required for a particular job, have
your Yamaha dealer perform it for you.1. Tool kit
1
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Periodic maintenance an d a djustment
9-10
9
2. Check the spark plug for electrode
erosion 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. 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.
TIPIf 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.TIPInstall 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.
Specifie d spark plu g:
NGK/CPR8EA-91. Spark plug gapSpark plu g g ap:
0.8–0.9 mm (0.031–0.035 in)
Ti ghtenin g torque:
Spark plug: 13 N·m (1.3 kgf·m, 9.6 lb·ft)
1. Spark plug cap
2. Spark plug lead
1
2
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Periodic maintenance an d a djustment
9-12
9
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 drain 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
damage and replace it if neces-
sary.
5. Install the engine oil strainer, com- pression spring, new O-ring and
engine oil drain bolt B.TIPMake 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.TIPBe sure to wipe off spilled oil on any
parts after the engine and exhaust sys-
tem have cooled down.NOTICE
ECA24060
Make sure that no forei gn material
enters the crankcase.
1. Engine oil drain bolt A
2. Gasket
3. Oil strainer
4. Compression spring
5. O-ring
6. Engine oil drain bolt B
2 3
4
5
6
1
Ti ghtenin g torque:
Engine oil drain bolt A: 20 N·m (2.0 kgf·m, 15 lb·ft)
Engine oil drain bolt B:
20 N·m (2.0 kgf·m, 15 lb·ft)
Recommen ded en gine oil:
See page 11-1.
Oil quantity: 0.90 L (0.95 US qt, 0.79 Imp.qt)
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Periodic maintenance an d a djustment
9-14
9
5. Remove the final transmission oil
drain bolt and its gasket to drain
the oil from the final transmission
case. 6. Install the final transmission oil
drain bolt and its new gasket, and
then tighten the bolt to the speci-
fied torque.
TIPBefore installing the final transmis-
sion oil drain bolt and gasket, ap-
ply oil to them.
 Wipe off any excess oil after-
wards.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.
1. Final transmission oil filler cap
2. O-ring
1. Final transmission oil drain bolt
2. Gasket
1
2
12
Ti ghtenin g torque:
Final transmission oil drain bolt:
20 N·m (2.0 kgf·m, 15 lb·ft)
Recommen ded final transmission
oil: See page 11-1.
Oil quantity:
0.10 L (0.11 US qt, 0.09 Imp.qt)
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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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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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