2007 YAMAHA PW50 engine

TABLE OF CONTENTS
SAFETY INFORMATION
...................1-1
Safe riding ........................................1-1
Location of important labels .............1-4
DESCRIPTION
...................................2-1
Left view ...........................................2-1
Right view .........................................2-2
Controls and instruments..................2-3
INSTRUMENT AND CONTROL
FUNCTIONS
........................................3-1
Handlebar switch .............................3-1
Speed limiter and power reduction
plate .............................................3-1
Front brake lever .............................3-2
Rear brake lever ..............................3-3
Fuel tank cap ...................................3-3
Fuel ..................................................3-3
Fuel tank breather hose ...................3-5
2-stroke engine oil ...........................3-5
Fuel cock .........................................3-5
Starter (choke) lever “
1
” .................3-6
Kickstarter ........................................3-6
Seat .................................................3-7
PRE-OPERATION CHECKS
...............4-1
Pre-operation check list ...................4-2
OPERATION AND IMPORTANT
RIDING POINTS
.................................. 5-1
Starting and warming up a cold
engine .......................................... 5-1
Starting a warm engine ................... 5-1
Starting off ....................................... 5-2
Acceleration and deceleration ......... 5-2
Braking ............................................ 5-2
Engine break-in ............................... 5-3
Parking ............................................ 5-4
PERIODIC MAINTENANCE AND
MINOR REPAIR
.................................. 6-1
Owner’s tool kit ................................ 6-1
Periodic maintenance chart for the
emission control system .............. 6-2
General maintenance and lubrication
chart ............................................. 6-3
Checking the spark plug .................. 6-5
Removing the power reduction
plate ............................................. 6-6
Transmission oil .............................. 6-7
Middle and final gear cases ............ 6-8
Cleaning the air filter element ......... 6-8
Cleaning the spark arrester ............. 6-9
Adjusting the carburetor ................ 6-10
Adjusting the engine idling
speed ......................................... 6-10
Checking the throttle cable free
play ............................................ 6-11
Tires .............................................. 6-11Panel wheels ................................. 6-13
Accessories and replacement
parts ........................................... 6-13
Adjusting the front and rear brake
lever free play ............................ 6-14
Checking the front and rear brake
shoes ......................................... 6-15
Checking and lubricating the
cables ........................................ 6-15
Checking and lubricating the throttle
grip and cable ............................ 6-16
Adjusting the Autolube pump ........ 6-16
Lubricating the front and rear brake
levers ......................................... 6-16
Checking and lubricating the
centerstand ................................ 6-17
Checking the front fork .................. 6-17
Checking the steering ................... 6-18
Checking the wheel bearings ........ 6-18
Front wheel ................................... 6-19
Rear wheel .................................... 6-20
Troubleshooting ............................ 6-23
Troubleshooting chart ................... 6-24
MOTORCYCLE CARE AND
STORAGE
........................................... 7-1
Care ................................................ 7-1
Storage ........................................... 7-3
SPECIFICATIONS
............................. 8-1

1-1
1
SAFETY INFORMATION
EAU40931
Safe riding

Always make pre-operation
checks. Careful checks may help
prevent an accident.

This motorcycle is designed for
off-road use only, therefore, it is il-
legal to operate it on public streets,
roads, or highways, even a dirt or
gravel one. Off-road use on public
lands may be illegal. Please check
local regulations before riding.

This motorcycle is designed to car-
ry the operator only. No passen-
gers.

Many accidents involve inexperi-
enced operators.

Make sure that the operator is
qualified and that you only lend
your motorcycle to other quali-
fied operators.

Know your skills and limits.
Staying within your limits may
help you to avoid an accident.

Many accidents have been caused
by error of the motorcycle opera-
tor. A typical error made by the op-
erator 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 operation
to maintain control of the motorcy-
cle.

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 preven-
tion 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 impairmentof vision that could delay seeing a
hazard.

The use of a jacket, heavy boots,
trousers, gloves, etc., is effective in
preventing or reducing abrasions
or lacerations.

Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.

Never touch the engine or exhaust
system during or after operation.
They become very hot and can
cause burns. Always wear protec-
tive clothing that covers your legs,
ankles, and feet.
Modifications
Modifications made to this motorcycle
not approved by Yamaha, or the re-
moval of original equipment, may ren-
der the motorcycle unsafe for use and
may cause severe personal injury.
Modifications may also make your mo-
torcycle illegal to use.
Loading and accessories
Adding accessories to your motorcycle

SAFETY INFORMATION
1-3
1
engine power.
Gasoline and exhaust gas

GASOLINE IS HIGHLY FLAMMA-
BLE:

Always turn the engine off when
refueling.

Take care not to spill any gaso-
line on the engine or exhaust
pipe/muffler when refueling.

Never refuel while smoking or in
the vicinity of an open flame.

Never start the engine or let it run
for any length of time in a closed
area. The exhaust fumes are poi-
sonous and may cause loss of
consciousness and death within a
short time. Always operate your
motorcycle in an area that has ad-
equate ventilation.

Always turn the engine off before
leaving the motorcycle unattend-
ed. When parking the motorcycle,
note the following:

The engine and exhaust pipe/
muffler may be hot, therefore,
park the motorcycle in a place
where pedestrians or childrenare not likely to touch these hot
areas.

Do not park the motorcycle on a
slope or soft ground, otherwise it
may fall over.

Do not park the motorcycle near
a flammable source (e.g., a ker-
osene heater, or near an open
flame), otherwise it could catch
fire.

When transporting the motorcycle
in another vehicle, make sure that
it is kept upright and that the fuel
cock is turned to “S” (stop). If the
motorcycle should lean over, gas-
oline may leak out of the carbure-
tor or fuel tank.

If you should swallow any gaso-
line, inhale a lot of gasoline vapor,
or allow gasoline to get into your
eyes, see your doctor immediate-
ly. If any gasoline spills on your
skin or clothing, immediately wash
the affected area with soap and
water and change your clothes.

DESCRIPTION
2-2
2
3
4
5
6
7
8
9

EAU10420
Right view
3
12
4

1. Spark arrester (page 6-9)
2. Seat (page 3-7)
3. Transmission oil filler cap (page 6-7)
4. 2-stroke engine oil tank (page 3-5)

DESCRIPTION
2-3
1
2
3
4
5
6
7
8
9

EAU10430
Controls and instruments
12
7 345
6

1. Rear brake lever (page 3-3)
2. Starter (choke) lever (page 3-6)
3. 2-stroke engine oil tank cap (page 3-5)
4. Right handlebar switch (page 3-1)
5. Front brake lever (page 3-2)
6. Throttle grip (page 6-11)
7. Fuel tank cap (page 3-3)

3-1
2
34
5
6
7
8
9

INSTRUMENT AND CONTROL FUNCTIONS
EAU40660
Handlebar switch
EAU40673
Engine stop switch “OFF/RUN/
START”
Set this switch to “START” before start-
ing 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.
NOTE:


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 motorcyclecannot be ridden in that switch po-
sition.
EAU41041
Speed limiter and power
reduction plate
Your motorcycle was delivered 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 they learn.
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).
1. Engine stop switch “OFF/RUN/START”
1

INSTRUMENT AND CONTROL FUNCTIONS
3-4
1
2
3
4
5
6
7
8
9
CAUTION:

ECA10070
Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since
fuel may deteriorate painted surfac-
es or plastic parts.
EAU41980
For Canada
CAUTION:

ECA15590
Use only unleaded gasoline. The use
of leaded gasoline will cause severe
damage to internal engine parts,
such as the piston rings as well as to
the exhaust system.
Your Yamaha engine has been de-
signed to use regular unleaded gaso-
line with a pump octane number
[(R+M)/2] of 86 or higher, or a research
octane number of 91 or higher. Ifknocking (or pinging) occurs, use a
gasoline of a different brand or premi-
um unleaded fuel. Use of unleaded fuel
will extend spark plug life and reduce
maintenance cost.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that contain-
ing methanol. Gasohol containing
ethanol can be used if ethanol content
does not exceed 10%. Gasohol con-
taining methanol is not recommended
by Yamaha because it can cause dam-
age to the fuel system or vehicle perfor-
mance problems.
Except for Canada
CAUTION:

ECA15590
Use only unleaded gasoline. The use
of leaded gasoline will cause severedamage to internal engine parts,
such as the piston rings as well as to
the exhaust system.
Your Yamaha engine has been de-
signed to use regular unleaded gaso-
line with a research octane number of
91 or higher. If knocking (or pinging) oc-
curs, use a gasoline of a different brand
or premium unleaded fuel. Use of un-
leaded fuel will extend spark plug life
and reduce maintenance costs.
Recommended fuel:
REGULAR UNLEADED GASOLINE
ONLY
Fuel tank capacity:
2.0 L (0.53 US gal) (0.44 Imp.gal)
Recommended fuel:
For Europe: REGULAR UNLEADED
GASOLINE ONLY
Except for Canada and Europe: UN-
LEADED GASOLINE ONLY
Fuel tank capacity:
2.0 L (0.53 US gal) (0.44 Imp.gal)

INSTRUMENT AND CONTROL FUNCTIONS
3-5
2
34
5
6
7
8
9

EAU13411
Fuel tank breather hose
Before operating the motorcycle:

Check the fuel tank breather hose
connection.

Check the fuel tank breather hose
for cracks or damage, and replace
it if damaged.

Make sure that the end of the fuel
tank breather hose is not blocked,
and clean it if necessary.
EAU13452
2-stroke engine oil
Make sure that there is sufficient
2-stroke engine oil in the oil tank. Add
the recommended 2-stroke engine oil
as necessary.
NOTE:

Make sure that the 2-stroke engine oil
tank cap is properly installed.
EAU40701
Fuel cock
The fuel cock supplies fuel from the
tank to the carburetor while filtering it al-
so.
The fuel cock has two positions:
S (stop)
With the lever in this position, fuel will
not flow. Always return the lever to this
position when the engine is not running.
1. Fuel tank breather hose
1

1. 2-stroke engine oil tank cap
2. Minimum level mark
Recommended oil:
See page 8-1.
Oil quantity:
0.30 L (0.32 US qt) (0.26 Imp.qt)
21

1. Arrow mark pointing to “S” (stop)
1