2020 YAMAHA PW50 engine

Periodic maintenance an d a djustment
7-7
7
To install the spark plu
g
1. Clean the surface of the spark plug gasket and its mating surfa-
ce, 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.
TIP
If 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.
EAU41104
Removin g the power re duc-
tion plate
To obtain full engine performance ca-
pability, removing the power reduction
plate is required.
1. Remove the exhaust manifold by removing the bolts. WARNING!
Always let the exhaust system
cool prior to touching exhaust
components.
[EWA14582]
2. Remove the gasket.
3. Remove the power reduction plate.
Tightening torque:
Spark plug: 20 N·m (2.0 kgf·m, 15 lb·ft)
1. Exhaust manifold bolt
1. Exhaust manifold
2. Gasket
3. Power reduction plate
1
1
2
3
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Periodic maintenance an d a djustment
7-8
7
TIP
Store the power reduction plate with
the Owner’s Manual so that it is readily
available whenever you want to reduce
the engine power.
4. Install the exhaust manifold and its
new gasket by installing the bolts,
and then tighten the bolts to the
specified torque.
EAU40896
Transmission oil
The transmission must be checked for
oil leakage before each ride. If any
leakage is found, have a Yamaha deal-
er check and repair the motorcycle. In
addition, the transmission oil must be
changed at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
To chan ge the transmission oil
1. Place the motorcycle on the cen- terstand.
2. Place an oil pan under the trans- mission to collect the used oil.
3. Remove the transmission oil filler cap, the transmission oil drain bolt
and its gasket to drain the oil from
the transmission.
Tightenin g torque:
Exhaust manifold bolt: 9 N·m (0.9 kgf·m, 6.6 lb·ft)
1. Transmission oil filler cap
1. Transmission oil drain bolt
2. Gasket
1
12
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Periodic maintenance an d a djustment
7-9
7
4. Install the transmission oil drain
bolt and its new gasket, and then
tighten the bolt to the specified
torque.
5. Refill with the specified amount of the recommended transmission
oil.
NOTICE
ECA10453
In or der to prevent clutch slip-
pa ge (since the transmission oil
also lu bricates the clutch), do
not mix any chemical additives.
Do not use oils with a diesel
specification of “CD” or oils of a
hi gher quality than specifie d. In
a ddition, do not use oils la bele d
“ENERGY CONSERVING II” or
hi gher.
 Make sure that no forei gn mate-
rial enters the transmission.
6. Check the O-ring for damage, and replace it if necessary. 7. Install and tighten the transmis-
sion oil filler cap.
8. Start the engine, and then let it idle for several minutes while checking
the transmission for oil leakage. If
oil is leaking, immediately turn the
engine off and check for the cau-
se.
Tightening torque:
Transmission oil drain bolt: 14 N·m (1.4 kgf·m, 10 lb·ft)
Recommen ded transmission oil:
See page 9-1.
Oil chan ge quantity:
0.30 L (0.32 US qt, 0.26 Imp.qt)
1. O-ring
1
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Periodic maintenance an d a djustment
7-12
7 3. Insert the tailpipe into the muffler,
and then install and tighten the
screw.
TIP
Make sure to align the screw hole
when inserting the tailpipe.
EAU39931
Adjustin g the car buretor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the nec-
essary professional knowledge and ex-
perience. The adjustment described in
the following section, however, may be
serviced by the owner as part of rou-
tine maintenance.
NOTICE
ECA10551
The car buretor has been set an d ex-
tensively teste d at the Yamaha fac-
tory. Chan gin g these settin gs
without sufficient technical knowl-
e dge may result in poor perfor-
mance of or d amage to the en gine.
1. Spark arrester
1
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Periodic maintenance an d a djustment
7-13
7
EAU21363
A djustin g the eng ine idlin g
spee d
The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
TIP
A diagnostic tachometer is needed to
make this adjustment.
1. Attach the tachometer to the
spark plug lead.
2. Start the engine and warm it up for several minutes at 1000–2000
r/min while occasionally revving it
to 4000–5000 r/min.
TIP
The engine is warm when it quickly re-
sponds to the throttle.
3. Check the engine idling speedand, if necessary, adjust it to
specification by turning the throt-
tle stop screw. To increase the en-
gine idling speed, turn the screw in
direction (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
TIP
If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
1. Throttle stop screw
1 (a)
(b)
En
gine i dlin g spee d:
1650–1750 r/min
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Periodic maintenance an d a djustment
7-20
7
EAU23121
A djustin g the Autolu be pump
The Autolube pump is a vital and so-
phisticated component of the engine,
which must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
EAU43634
Lub ricatin g the front an d rear
b rake levers
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:
Lithium-soap-based grease
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Periodic maintenance an d a djustment
7-28
7
EAU68120
Trou bleshootin g chart
1. FuelThere is enough fuel.
There is no fuel.
Check the ignition.
Supply fuel.The engine does not
start.
Check the ignition.
Open the throttle
halfway and operate
the kickstarter.Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug.
2. IgnitionWet
Dry
There is compression.
There is no
compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
Operate the
kickstarter.
Check the fuel level
in the fuel tank.
3. Compression
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Motorcycle care and stora ge
8-1
8
EAU37834
Matte color caution
NOTICE
ECA15193
Some mo dels are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
a d vice on what pro ducts to use be-
fore cleanin g the vehicle. Usin g a
b rush, harsh chemical prod ucts or
cleanin g compoun ds when cleanin g
these parts will scratch or damag e
their surface. Wax also shoul d not
b e applie d to any matte colored fin-
ishe d parts.
EAU40636
Care
While the open design of a motorcycle
reveals the attractiveness of the tech-
nology, it also makes it more vulnera-
ble. Rust and corrosion can develop
even if high-quality components are
used. A rusty exhaust pipe may go un-
noticed on a car, however, it detracts
from the overall appearance of a mo-
torcycle. Frequent and proper care
does not only comply with the terms of
the warranty, but it will also keep your
motorcycle looking good, extend its
life and optimize its performance.
Before cleanin g
1. Cover the muffler outlet with a plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov- ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt, like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such prod-
ucts onto seals, gaskets and
wheel axles. Always rinse the dirt
and degreaser off with water.
Cleanin g
NOTICE
ECA17111
Avoi d using strong aci dic wheel
cleaners, especially on spoked
wheels. If such pro ducts are
use d on har d-to-remove dirt, do
not leave the cleaner on the af-
fected area any lon ger than in-
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