2021 YAMAHA PW50 check 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 Reporting safety defects (For
CA NADA
c

ustomers) ................. 10-3
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Safety information
2-3
2
ventilated 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 overload ed 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
2Aftermarket 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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Operation and important ri din g points
6-2
6
EAU16661
Startin g a warm en gine
Follow the same procedure as for
starting a cold engine with the excep-
tion that the starter (choke) is not re-
quired when the engine is warm.
Instead, start the engine with the throt-
tle slightly open.
TIP
If the engine does not start after sever-
al kicks, try again with the throttle 1/4
to 1/2 open.
EAU41004
Startin g off
1. While applying the rear brake le-
ver, push the motorcycle off the
centerstand.
2. Completely close the throttle.
3. Set the engine stop switch to “RUN”.
4. Check for oncoming off-road vehi- cles, release the rear brake lever,
and then slowly turn the throttle
grip in order to take off.
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Operation and important ri din g points
6-4
6
EAU42031
En gine break-in
There is never a more important period
in the life of your engine than the first 5
hours of riding. It is also important to
accustom the rider to the motorcycle
during this time. Please read the fol-
lowing information carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
5 hours of operation. The various parts
in the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheating
must be avoided. However, momen-
tary full-throttle operation under load
(i.e., two to three seconds maximum)
does not harm the engine. Each full-
throttle acceleration should be fol-
lowed with a substantial rest period for
the engine. To allow the engine to cool
down from the temporary buildup of
heat, cruise at a lower engine speed.
After the first 5 hours of operation,
thoroughly check the motorcycle for
loose parts, oil leakage and any other
problems. Be sure to inspect and make
adjustments thoroughly, especially ca-
bles. In addition, check all fittings and
fasteners for looseness, and tighten if
necessary.
NOTICE
ECA10271
If any en gine trou ble shoul d occur
d uring the en gine break-in perio d,
imme diately have a Yamaha d ealer
check the vehicle.
EAU40723
Parkin g
When parking, stop the engine, and
then turn the fuel cock lever to “S”
(stop).
WARNING
EWA10312
Since the en gine an d exhaust
system can become very hot,
park in a place where ped estri-
ans or chil dren are not likely to
touch them and b e burne d.
 Do not park on a slope or on soft
groun d, otherwise the vehicle
may overturn, increasin g the
risk of a fuel leak an d fire.
 Do not park near grass or other
flammab le materials which
mi ght catch fire.
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Periodic maintenance an d a djustment
7-3
7
EAU69180
Perio dic maintenance chart for the emission control system
TIP
Items marked with an asterisk should be performed by a Yamaha dealer as they
require special tools, data and technical skills.
4 *Carburetor Check engine idling speed and
starter operation.
Adjust if necessary.
Clean.
5 *Cylinder head and
exhaust system Check for leakage.
√
Tighten if necessary.
Decarbonize if necessary.
6
*Spark arrester Clean.√
NO. ITEM CHECK OR MAINTENANCE JOB
1 month3 months
6 months
6 months12 months
1
*Fuel line Check fuel hoses for cracks or
damage.√√√ √
√√√ √
√√
√
√
√√
√
√
√√
√ Replace if necessary.
2Spark plug Check condition.
Adjust gap and clean.
Replace if necessary.
3Air filter element
Clean with solvent.
Replace if necessary.
THEREAFTER
EVERYINITIAL
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Periodic maintenance an d a djustment
7-6
7
EAU19607
Checkin g the spark plu g
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic main-
tenance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
To remove the spark plu g
1. Remove the spark plug cap.
2. Remove the spark plug as shown, with the spark plug wrench includ-
ed in the owner’s tool kit. To check the spark plu
g
1. Check that the porcelain insulator around the center electrode of the
spark plug is a medium-to-light
tan (the ideal color when the vehi-
cle is ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrodeerosion 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.
1. Spark plug cap
1. Spark plug wrench
1
1
Specified spark plu g:
NGK/BP4HS (South Africa)
NGK/BPR4HS (Canada, Europe,
Oceania)
DENSO/W14FP-L (South Africa)
1. Spark plug gap
Spark plu g g ap:
0.6–0.7 mm (0.024–0.028 in)
1
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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.
Tightening 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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