2021 YAMAHA NMAX 155 fuel pressure

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
9-19
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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Motorcycle care and stora ge
10-4
10 1. Make all necessary repairs and
perform any outstanding mainte-
nance.
2. Follow all instructions in the Care section of this chapter.
3. Fill up the fuel tank, adding fuel stabilizer according to product in-
structions. Run the engine for 5
minutes to distribute treated fuel
through the fuel system.
4. For vehicles equipped with a fuel cock: Turn the fuel cock lever to
the off position.
5. For vehicles with a carburetor: To prevent fuel deposits from build-
ing up, drain the fuel in the carbu-
retor float chamber into a clean
container. Retighten the drain bolt
and pour the fuel back into the fuel
tank.
6. Use a quality engine fogging oil according to product instructions
to protect internal engine compo-
nents from corrosion. If engine
fogging oil is not available, per-
form the following steps for each
cylinder:a. Remove the spark plug cap and spark plug. b. Pour a teaspoonful of engine
oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several times with the starter. (This will
coat the cylinder wall with oil.)
WARNING! To prevent d am-
a g e or injury from sparkin g,
make sure to groun d the
spark plu g electro des while
turnin g the en gine over.
[EWA10952]
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
7. Lubricate all control cables, piv- ots, levers and pedals, as well as
the sidestand and centerstand (if
equipped).
8. Check and correct the tire air pressure, and then lift the vehicle
so that all wheels are off the
ground. Otherwise, turn the wheels a little once a month in or-
der to prevent the tires from be-
coming degraded in one spot.
9. Cover the muffler outlet with a plastic bag to prevent moisture
from entering it.
10. Remove the battery and fully charge it, or attach a maintenance
charger to keep the battery opti-
mally charged. NOTICE: Confirm
that the battery an d its char ger
are compati ble. Do not char ge a
VRLA battery with a convention-
al char ger.
[ECA26330]
TIP If the battery will be removed,
charge it once a month and store
it in a temperate location between
0-30 °C (32-90 °F).
 See page 9-28 for more informa-
tion on charging and storing the
battery.
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