2021 YAMAHA PW50 check engine

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), d o
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
cause.
Tightenin g 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
U2SA87E0.book Page 9 Monday, April 6, 2020 3:00 PM

Periodic maintenance an d a djustment
7-13
7
EAU21363
A djustin g the en gine i dlin 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
U2SA87E0.book Page 13 Monday, April 6, 2020 3:00 PM

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
U2SA87E0.book Page 28 Monday, April 6, 2020 3:00 PM

Motorcycle care and stora ge
8-4
8
5. Perform the following steps to
protect the cylinder, piston rings,
etc. from corrosion.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.)
e. Remove the spark plug cap from the spark plug, and then
install the spark plug and the
spark plug cap. WARNING! To
prevent damag e or injury
from sparkin g, make sure to
g roun d the spark plu g elec-
tro des while turning the en-
g ine over. [EWA10952]
6. Lubricate all control cables and
the pivoting points of all levers as
well as of the centerstand.
7. Check and, if necessary, correct the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
8. Cover the muffler outlet with a plastic bag to prevent moisture
from entering it.
TIP
Make any necessary repairs before
storing the motorcycle.
U2SA87E0.book Page 4 Monday, April 6, 2020 3:00 PM

11-1
11
Index
A
Acceleration and deceleration ................ 6-3
Air filter element, cleaning .................... 7-10
Autolube pump, adjusting..................... 7-20
B
Brake lever, front .................................... 4-2
Brake lever, rear...................................... 4-3
Brake levers, lubricating ....................... 7-20
Brake shoes, checking ......................... 7-18
Braking.................................................... 6-3
C
Cable lock (for Europe) ........................... 4-9
Cables, checking and lubricating ......... 7-19
Carburetor, adjusting ............................ 7-12
Care ........................................................ 8-1
Centerstand, checking and
lubricating ........................................... 7-21
E
Engine break-in....................................... 6-4
Engine idling speed .............................. 7-13
Engine oil ................................................ 4-6
Engine serial number ............................ 10-1
Engine, starting a warm .......................... 6-2
Engine stop switch ................................. 4-1
F
Front and rear brake lever free play, adjusting ............................................. 7-17
Front fork, checking .............................. 7-21
Fuel ......................................................... 4-4
Fuel cock ................................................ 4-6
Fuel tank breather hose .......................... 4-5
Fuel tank cap .......................................... 4-3
H
Handlebar switch .................................... 4-1
I
Identification numbers .......................... 10-1
K
Kickstarter............................................... 4-7
L
Labels, location....................................... 1-1
M
Maintenance and lubrication, periodic ... 7-4
Maintenance, emission control system .................................................. 7-3
Matte color, caution ................................ 8-1
Middle and final gear cases .................. 7-10
P
Parking .................................................... 6-4
Part locations .......................................... 3-1
Power reduction plate, removing............ 7-7
S
Safety defects, reporting (For CANADA customers) ......................................... 10-3
Safety information .................................. 2-1
Seat ........................................................ 4-8
Spark arrester, cleaning ....................... 7-11
Spark plug, checking ............................. 7-6
Specifications ......................................... 9-1
Speed limiter and power reduction plate ..................................................... 4-1
Starter (choke) lever ............................... 4-7
Starting and warming up a cold engine .................................................. 6-1
Starting off.............................................. 6-2
Steering, checking................................ 7-22
Storage ................................................... 8-3
T
Throttle grip and cable, checking and lubricating .......................................... 7-19
Throttle grip free play, checking........... 7-14
Tires ...................................................... 7-14
Tool kit.................................................... 7-2
Transmission oil ..................................... 7-8
Troubleshooting ................................... 7-27
Troubleshooting chart .......................... 7-28
V
Vehicle Emission Control Information label (For Canada) .............................. 10-1
Vehicle identification number ............... 10-1
W
Wheel bearings, checking .................... 7-22
Wheel (front) ......................................... 7-23
Wheel (rear) .......................................... 7-24
Wheels .................................................. 7-16
U2SA87E0.book Page 1 Monday, April 6, 2020 3:00 PM