2020 YAMAHA PW50 engine

Table of contents
Location of important la bels ........... 1-1
Safety information ............................ 2-1
Description ....................................... 3-1
Left view ......................................... 3-1
Right view ....................................... 3-2
Controls and instruments ............... 3-3
Instrument an d control functions ... 4-1
Handlebar switch............................ 4-1
Speed limiter and power reduction
plate ............................................ 4-1
Front brake lever ............................ 4-2
Rear brake lever ............................. 4-3
Fuel tank cap .................................. 4-3
Fuel ................................................. 4-4
Fuel tank breather hose.................. 4-5
2-stroke engine oil .......................... 4-6
Fuel cock ........................................ 4-6
Starter (choke) lever ...................... 4-7
Kickstarter ...................................... 4-7
Seat ................................................ 4-8
Cable lock (for Europe) ................... 4-9
For your safety – pre-operation
checks ............................................... 5-1
Operation an d important ri din g
points ................................................ 6-1
Starting and warming up a cold engine ......................................... 6-1
Starting a warm engine .................. 6-2
Starting off ...................................... 6-2
Acceleration and deceleration ........ 6-3
Braking ........................................... 6-3
Engine break-in .............................. 6-4
Parking ........................................... 6-4
Perio dic maintenance an d
a d justment ........................................ 7-1
Owner’s tool kit .............................. 7-2
Periodic maintenance chart for the emission control system ............. 7-3
General maintenance and
lubrication chart .......................... 7-4 Checking the spark plug ................. 7-6
Removing the power reduction
plate ............................................. 7-7
Transmission oil .............................. 7-8
Middle and final gear cases .......... 7-10
Cleaning the air filter element ....... 7-10
Cleaning the spark arrester ........... 7-11
Adjusting the carburetor ............... 7-12
Adjusting the engine idling speed ......................................... 7-13
Checking the throttle grip free
play ............................................ 7-14
Tires .............................................. 7-14
Panel wheels ................................. 7-16
Adjusting the front and rear brake lever free play ............................ 7-17
Checking the front and rear brake
shoes ......................................... 7-18
Checking and lubricating the cables ........................................ 7-19
Checking and lubricating the throttle grip and cable ............... 7-19
Adjusting the Autolube pump ....... 7-20
Lubricating the front and rear
brake levers ............................... 7-20
Checking and lubricating the
centerstand ................................ 7-21
Checking the front fork ................. 7-21
Checking the steering ................... 7-22
Checking the wheel bearings ........ 7-22
Front wheel ................................... 7-23
Rear wheel .................................... 7-24
Troubleshooting ............................ 7-27
Troubleshooting chart ................... 7-28
Motorcycle care an d stora ge .......... 8-1
Matte color caution ......................... 8-1
Care................................................. 8-1
Storage............................................ 8-3
Specifications ................................... 9-1
Consumer information ................... 10-1
Identification numbers .................. 10-1
In dex ................................................ 11-1
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Safety information
2-2
2

Many accidents involve inexperi-
enced operators.
• Make sure that you are qualified and that you only lend your mo-
torcycle to other qualified oper-
ators.
• Know your skills and limits. Staying within your limits may
help you to avoid an accident.
• We recommend that you prac- tice riding your motorcycle until
you have become thoroughly
familiar with the motorcycle and
all of its controls.
 Many accidents have been
caused by error of the motorcycle
operator. A typical error made by
the operator is veering wide on a
turn due to excessive speed or un-
dercornering (insufficient lean an-
gle for the speed). Never travel
faster than warranted by condi-
tions.
 Ride cautiously in unfamiliar ar-
eas. You may encounter hidden
obstacles that could cause an ac-
cident.
 The posture of the operator is im-
portant for proper control. The op-
erator should keep both hands on
the handlebar and both feet on the
operator footrests during opera-
tion to maintain control of the mo-
torcycle.
 Never ride under the influence of
alcohol or other drugs. Protective Apparel
The majority of fatalities from motorcy-
cle accidents are the result of head in-
juries. The use of a safety helmet is the
single most critical factor in the pre-
vention or reduction of head injuries.
 Always wear an approved helmet.
 Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision that could delay seeing a
hazard.
 The use of a jacket, heavy boots,
trousers, gloves, etc., is effective
in preventing or reducing abra-
sions or lacerations.
 Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.
 Always wear protective clothing
that covers your legs, ankles, and
feet. The engine or exhaust sys-
tem become very hot during or af-
ter operation and can cause
burns.
Avoi d Car bon Monoxi de Poisonin g
All engine exhaust contains carbon
monoxide, a deadly gas. Breathing
carbon monoxide can cause head-
aches, dizziness, drowsiness, nausea,
confusion, and eventually death.
Carbon Monoxide is a colorless, odor-
less, tasteless gas which may be pres-
ent even if you do not see or smell any
engine exhaust. Deadly levels of car-
bon monoxide can collect rapidly and
you can quickly be overcome and un-
able to save yourself. Also, deadly lev-
els of carbon monoxide can linger for
hours or days in enclosed or poorly
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Safety information
2-3
2ventilated areas. If you experience any
symptoms of carbon monoxide poi-
soning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREAT-
MENT.
 Do not run engine indoors. Even if
you try to ventilate engine exhaust
with fans or open windows and
doors, carbon monoxide can rap-
idly reach dangerous levels.
 Do not run engine in poorly venti-
lated or partially enclosed areas
such as barns, garages, or car-
ports.
 Do not run engine outdoors where
engine exhaust can be drawn into
a building through openings such
as windows and doors.
Loa din g
Adding accessories to your motorcycle
can adversely affect stability and han-
dling if the weight distribution of the
motorcycle is changed. To avoid the
possibility of an accident, use extreme
caution when adding accessories to
your motorcycle. Use extra care when
riding a motorcycle that has added ac-
cessories. Here are some general
guidelines to follow if adding accesso-
ries to your motorcycle:
Operation of an overloa ded vehicle
coul d cause an acci dent.
 The weight of the operator must
not exceed 25 kg (55 lb).
 Accessory weight should be kept
as low and close to the motorcy-
cle as possible. Securely pack
your heaviest items as close to the
center of the vehicle as possible
and make sure to distribute the weight as evenly as possible on
both sides of the motorcycle to
minimize imbalance or instability.
 Shifting weights can create a sud-
den imbalance. Make sure that
accessories are securely attached
to the motorcycle before riding.
Check accessory mounts fre-
quently.
• Properly adjust the suspension for your load (suspension-ad-
justable models only), and
check the condition and pres-
sure of your tires.
• Never attach any large or heavy items to the handlebar, front
fork, or front fender.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail- able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Many companies with no connection
to Yamaha manufacture parts and ac-
cessories or offer other modifications
for Yamaha vehicles. Yamaha is not in
a position to test the products that
these aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer.
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Safety information
2-4
2
Aftermarket Parts, Accessories, an
d
Mo difications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accesso-
ries or modifications are not suitable
because of potential safety hazards to
you or others. Installing aftermarket
products or having other modifications
performed to your vehicle that change
any of the vehicle’s design or operation
characteristics can put you and others
at greater risk of serious injury or
death. You are responsible for injuries
related to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.  Never install accessories that
would impair the performance of
your motorcycle. Carefully inspect
the accessory before using it to
make sure that it does not in any
way reduce ground clearance or
cornering clearance, limit suspen-
sion travel, steering travel or con-
trol operation.
• Accessories fitted to the han- dlebar or the front fork area can
create instability due to improp-
er weight distribution. If acces-
sories are added to the
handlebar or front fork area,
they must be as lightweight as
possible and should be kept to
a minimum.
• Bulky or large accessories may seriously affect the stability of
the motorcycle. Wind may at- tempt to lift the motorcycle, or
the motorcycle may become
unstable in cross winds.
• Certain accessories can dis- place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
 Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires an d Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. Refer to page
7-14 for tire specifications and more in-
formation on replacing your tires.
Transportin g the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle.  Remove all loose items from the
motorcycle.
 Check that the fuel cock is in the
“S” (stop) position and that there
are no fuel leaks.
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Description
3-2
3
EAU63391
Right view
12345
6
1. Spark arrester (page 7-11)
2. Seat (page 4-8)
3. Transmission oil filler cap (page 7-8)
4. Fuel tank cap (page 4-3)
5. 2-stroke engine oil tank cap (page 4-6)
6. Transmission oil drain bolt (page 7-8)
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Description
3-3
3
EAU63401
Controls and instruments
1
234
5
1. Rear brake lever (page 4-3)
2. Starter (choke) lever (page 4-7)
3. Engine stop switch (page 4-1)
4. Front brake lever (page 4-2)
5. Throttle grip (page 7-14)
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Instrument and control functions
4-1
4
EAU40661
Han dle bar switch
EAU40675En gine stop switch
“OFF/RUN/START”
Set this switch to “START” before
starting the engine. Set this switch to
“RUN” after warming up the engine or
before starting off. Set this switch to
“OFF” to stop the engine.
TIP
 The engine cannot be started with
this switch set to the “RUN” posi-
tion.
 The engine speed is limited while
this switch is set to the “START”
position, therefore the motorcycle
cannot be ridden in that switch
position.
EAU41045
Spee d limiter an d power re-
d uction plate
Your motorcycle is equipped with an
adjustable speed limiter and a power
reduction plate. The speed limiter
keeps the throttle from fully opening,
even when the throttle grip is turned to
the maximum. The power reduction
plate is installed in the exhaust mani-
fold to limit the amount of power avail-
able while learning.
Speed limiter
1. Loosen the locknut.
2. To increase the maximum engine power available and the maximum
speed of the motorcycle, turn the
adjusting screw in direction (a). To
decrease the maximum engine
power available and the maximum
speed of the motorcycle, turn the
adjusting screw in direction (b).
3. Tighten the locknut.
1. Engine stop switch “OFF/RUN/START”
1
1. Locknut
2. Adjusting screw
1
(a) (b)2
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Instrument and control functions
4-4
4
EAU13213
Fuel
Make sure there is sufficient gasoline in
the tank.
WARNING
EWA10882
Gasoline an d gasoline vapors are
extremely flammab le. To avoid fires
an d explosions an d to re duce the
risk of injury when refueling , follow
these instructions.
1. Before refueling, turn off the en- gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. Stop filling when the fuel reaches the
bottom of the filler tube. Because
fuel expands when it heats up,
heat from the engine or the sun
can cause fuel to spill out of the
fuel tank.
3. Wipe up any spilled fuel immedi- ately. NOTICE: Immediately
wipe off spille d fuel with a clean, d
ry, soft cloth, since fuel may
d eteriorate painte d surfaces or
plastic parts.
[ECA10072]
4. Be sure to securely close the fuel tank cap.
WARNING
EWA15152
Gasoline is poisonous an d can cau-
se injury or death. Han dle gasoline
with care. Never siphon gasoline by
mouth. If you shoul d swallow some
g asoline or inhale a lot of gasoline
vapor, or get some g asoline in your
eyes, see your doctor imme diately. If
g asoline spills on your skin, wash
with soap an d water. If gasoline
spills on your clothin g, chan ge your
clothes.
EAU41987
NOTICE
ECA15591
Use only unlea ded g asoline. The use
of lead ed g asoline will cause severe
d amag e to internal en gine parts,
such as the piston rin gs as well as to
the exhaust system.
 For Canada: Use gasoline with a
pump octane number [(R+M)/2] of
86 or higher (research octane
number of 91 or higher).
 For Oceania and South Africa: Use
gasoline with a research octane
number of 91 or higher.
1. Fuel tank filler tube
2. Maximum fuel level
2
1
Recommen
ded fuel:
REGULAR UNLEADED GASOLINE
ONLY
Fuel tank capacity: 2.0 L (0.5 US gal, 0.4 Imp.gal)
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