Yamaha PW50W 2007 User manual

SERVICE MANUAL
5PG-28197-10
LIT-11616-20-15
PW50W
S5PG10_cover 2006.4.22 1:17 PM Page 1

PW50W
SERVICE MANUAL
©2006 by Yamaha Motor Corporation
U.S.A.
First edition May 2006
All rights reserved.
Any reproduction or unauthorized use
without the written permission of
Yamaha Motor Corporation U.S.A.
is expressly prohibited.
Printed in U.S.A.
P/N LIT-11616-20-15
EAS00000
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NOTICE
This manual was produced by the Yamaha Motor Company, Ltd. primarily for use by Yamaha dealers
and their ualified mechanics. It is not possible to include all the knowledge of a mechanic in one
manual. Therefore, anyone who uses this book to perform maintenance and repairs on Yamaha vehi-
cles should have a basic understanding of mechanics and the techni ues to repair these types of
vehicles. Repair and maintenance work attempted by anyone without this knowledge is likely to ren-
der the vehicle unsafe and unfit for use.
This model has been designed and manufactured to perform within certain specifications in regard
to performance and emissions. Proper service with the correct tools is necessary to ensure that the
vehicle will operate as designed. If there is any uestion about a service procedure, it is imperative
that you contact a Yamaha dealer for any service information changes that apply to this model. This
policy is intended to provide the customer with the most satisfaction from his vehicle and to conform
to federal environmental uality objectives.
Yamaha Motor Company, Ltd. is continually striving to improve all of its models. Modifications and
significant changes in specifications or procedures will be forwarded to all authorized Yamaha dealers
and will appear in future editions of this manual where applicable.
NOTE:
8This Service Manual contains information regarding periodic maintenance to the emission control
system. Please read this material carefully.
8Designs and specifications are subject to change without notice.
IMPORTANT MANUAL INFORMATION
Particularly important information is distinguished in this manual by the following.
QThe Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR SAFETY
IS INVOLVED!
wFailure to follow WARNING instructions could result in severe injury or death to the
vehicle operator, a bystander or a person checking or repairing the vehicle.
cCA CAUTION indicates special precautions that must be taken to avoid damage to
the vehicle.
NOTE: A NOTE provides key information to make procedures easier or clearer.
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HOW TO USE THIS MANUAL
This manual is intended as a handy, easy-to-read reference book for the mechanic.
Comprehensive explanations of all installation, removal, disassembly, assembly, repair and check
procedures are laid out with the individual steps in sequential order.
1The manual is divided into chapters. An abbreviation and symbol in the upper right corner of
each page indicate the current chapter.
efer to "SYMBOLS".
2Each chapter is divided into sections. The current section title is shown at the top of each page,
except in Chapter 3 ("PE IODIC CHECKS AND ADJUSTMENTS"), where the sub-section title(s)
appears.
3Sub-section titles appear in smaller print than the section title.
4To help identify parts and clarify procedure steps, there are exploded diagrams at the start of
each removal and disassembly section.
5Numbers are given in the order of the jobs in the exploded diagram. A circled number indicates
a disassembly step.
6Symbols indicate parts to be lubricated or replaced.
efer to "SYMBOLS".
7A job instruction chart accompanies the exploded diagram, providing the order of jobs, names
of parts, notes in jobs, etc.
8Jobs requiring more information (such as special tools and technical data) are described
sequentially.
1
2
6
3
5
4
7
8
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SYMBOLS
The following symbols are not relevant to
every vehicle.
Symbols 1to 8indicate the subject of each
chapter.
1General information
2Specifications
3Periodic checks and adjustments
4Chassis
5Engine
6Carburetor
7Electrical system
8Troubleshooting
Symbols 9to yindicate the following.
9Serviceable with engine mounted
0Filling fluid
qLubricant
wSpecial tool
eTightening torque
rWear limit, clearance
tEngine speed
yElectrical data
Symbols uto sin the exploded diagrams
indicate the types of lubricants and lubrication
points.
uEngine oil
iGear oil
oMolybdenum-disulfide oil
pWheel-bearing grease
aLithium-soap-based grease
sMolybdenum-disulfide grease
Symbols dto fin the exploded diagrams
indicate the following.
dApply locking agent (LOCTITE®)
feplace the part
12
34
56
78
90
qw
er
ty
ui o
pas
df
GEN
INFO SPEC
CHK
ADJ
ENG CARB
CHAS
ELEC TRBL
SHTG
LT
New
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SPECIFICATIONS
TROUBLESHOOTING
ELECTRICAL SYSTEM
CARBURETOR
CHASSIS
PERIODIC CHECKS AND
ADJUSTMENTS
GENERAL INFORMATION GEN
INFO
TRBL
SHTG
ELEC
CARB
CHAS
CHK
ADJ
SPEC
TABLE OF CONTENTS
4
6
7
8
3
2
1
ENGINE ENG
5
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GEN
INFO
CHAPTER 1
GENERAL INFORMATION
VEHICLE IDENTIFICATION .............................................................................1-1
VEHICLE IDENTIFICATION NUMBE .......................................................1-1
ENGINE SE IAL NUMBE .........................................................................1-1
IMPORTANT INFORMATION............................................................................1-2
P EPA ATION FO EMOVAL AND DISASSEMBLY ..............................1-2
EPLACEMENT PA TS .............................................................................1-2
GASKETS, OIL SEALS AND O- INGS ......................................................1-2
LOCK WASHE S/PLATES AND COTTE PINS .......................................1-3
BEA INGS AND OIL SEALS ......................................................................1-3
CI CLIPS ....................................................................................................1-3
CHECKING THE CONNECTIONS ...................................................................1-4
SPECIAL TOOLS .............................................................................................1-5
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1-1
GEN
INFO
VEHICLE IDENTIFICATION
GENERAL INFORMATION
VEHICLE IDENTIFICATION
VEHICLE IDENTIFICATION NUMBER
The number 1is stamped into the frame
head pipe.
ENGINE SERIAL NUMBER
The engine serial number 1is stamped into
the crankcase.
NOTE:
Designs and specifications are subject to
change without notice.
1
1
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GEN
INFO
IMPORTANT INFORMATION
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL AND DIS-
ASSEMBLY
1. Before removal and disassembly, remove
all dirt, mud, dust and foreign material.
2. Use only the proper tools and cleaning
equipment.
efer to the “SPECIAL TOOLS”.
3. When disassembling, always keep mated
parts together. This includes gears, cylin-
ders, pistons and other parts that have
been “mated” through normal wear.
Mated parts must always be reused or
replaced as an assembly.
4. During disassembly, clean all of the parts
and place them in trays in the order of
disassembly. This will speed up assembly
and allow for the correct installation of all
parts.
5. Keep all parts away from any source of
fire.
1-2
EAS00021
REPLACEMENT PARTS
Use only genuine Yamaha parts for all
replacements. Use oil and grease recom-
mended by Yamaha for all lubrication jobs.
Other brands may be similar in function and
appearance, but inferior in quality.
EAS00022
GASKETS OIL SEALS AND O-RINGS
1. When overhauling the engine, replace all
gaskets, seals and O-rings. All gasket
surfaces, oil seal lips and O-rings must be
cleaned.
2. During reassembly, properly oil all mating
parts and bearings and lubricate the oil
seal lips with grease.
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BEARINGS AND OIL SEALS
Install bearings and oil seals so that the man-
ufacturer’s marks or numbers are visible.
When installing oil seals, lubricate the oil seal
lips with a light coat of lithium-soap-based
grease. Oil bearings liberally when installing,
if appropriate.
1Oil seal
cC
Do not spin the bearing with compressed
air because this will damage the bearing
surfaces.
1Bearing
CIRCLIPS
Before reassembly, check all circlips carefully
and replace damaged or distorted circlips.
Always replace piston pin clips after one use.
When installing a circlip 1, make sure the
sharp-edged corner 2is positioned opposite
the thrust 3that the circlip receives.
4Shaft
GEN
INFO
IMPORTANT INFORMATION
1
300-000
300-003
1
300-002
1
300-001
3
4
1
2
LOCK WASHERS/PLATES AND COTTER
PINS
After removal, replace all lock washers/plates
1and cotter pins. After the bolt or nut has
been tightened to specification, bend the lock
tabs along a flat of the bolt or nut.
1-3
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GEN
INFO
CHECKING THE CONNECTIONS
1
CHECKING THE CONNECTIONS
Check the leads, couplers, and connecters for
stains, rust, moisture, etc.
1. Disconnect:
9lead
9coupler
9connector
2. Check:
9lead
9coupler
9connector
Moisture →Dry with compressed air.
ust/stains →Connect and disconnect
several times.
3. Check:
9all connections
Loose connection →Connect properly.
NOTE:
If the pin 1on the terminal is flattened, bend
it up.
4. Connect:
9lead
9coupler
9connector
NOTE:
Make sure all connections are tight.
5. Check:
9continuity
(with the pocket tester)
NOTE:
8If there is no continuity, clean the terminals.
8When checking the wire harness, perform
steps (1) to (3).
8As a quick remedy, use a contact revitalizer
available at most part stores.
1-4
Pocket tester
90890-03112 YM-03112
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GEN
INFO
SPECIAL TOOLS
1-5
SPECIAL TOOLS
The following special tools are necessary for complete and accurate tune-up and assembly. Use
only the appropriate special tools as this will help prevent damage caused by the use of inappro-
priate tools or improvised techniques. Special tools, part numbers or both may differ depending on
the country.
When placing an order, refer to the list provided below to avoid any mistakes.
90890-01235
YU-01235
otor holding tool
This tool is necessary for removing and
installing the rotor.
90890-01252
Dial gauge and stand set
These tools are for measuring the
crankshaft runout.
Crankshaft instoller pot
This tool is necessary for installing the
crankshaft.
90890-01274
YU-90058
Tool No. Tool name/Usage Illustration
90890-01275
YU-90060
Crankshaft installer bolt
This tool is necessary for installing the
crankshaft.
90890-01278
YU-90063
Adapter (M12)
This tool is necessary for installing the
crankshaft.
90890-01189
YM-01189
Flywheel puller
This tool is used for removing the rotor.
90890-01306
YM-01306
Hex. wrench (25 mm)
This tool is needed for removing the mid-
dle gear screw.
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GEN
INFO
SPECIAL TOOLS
1-6
90890-03112
YU-03112-U
Pocket tester
This instrument is necessary for
checking the electrical system.
Tool No. Tool name/Usage Illustration
Flywheel puller
This tool is used for separating the
crankcase.
90890-01362
YU-33270
90890-06754
YM-34487
Ignition checker
This instrument is necessary for check-
ing the ignition system components.
90890-01307
YM-01307
Hex. wrench (22 mm)
This tool is needed for removing the
shaft drive screw.
90890-06760
YU-06760
Digital tachometer
This tool is needed for observing engine
r/min.
90890-85505
Yamaha bond No.1215
(Three bond No.1215
)
This bond is used on crankcase
mating surfaces,etc.
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SPEC
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS ......................................................................... 2-1
MAINTENANCE SPECIFICATIONS ................................................................ 2-2
ENGINE ...................................................................................................... 2-2
CHASSIS ..................................................................................................... 2-6
ELECT ICAL .............................................................................................. 2-10
GENERAL TIGHTENING TORQUE SPECIFICATIONS .................................. 2-11
DEFINITION OF UNITS .................................................................................... 2-11
LUBRICATION POINTS AND LUBRICANT TYPES ....................................... 2-12
ENGINE ...................................................................................................... 2-12
CHASSIS ..................................................................................................... 2-12
CABLE ROUTING ............................................................................................ 2-13
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Model name: PW50W (Except for EU OPE)
PW50 (For EU OPE)
Model code number: 5PGD (Except for EU OPE)
5PGE (For EU OPE)
Dimensions:
Overall length 1245 mm (49.0 in)
Overall width 575 mm (22.6 in)
Overall height 715 mm (28.1 in)
Seat height 485 mm (19.1 in)
Wheelbase 855 mm (33.7 in)
Ground clearance 105 mm (4.13 in)
Minimum turning radius 1300 mm (51.2 in)
Weight:
With oil and fuel 39.0 kg (86 lb)
SPEC
GENERAL SPECIFICATIONS
2-1
SPECIFICATIONS
GENERAL SPECIFICATIONS
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Item PW50
Engine type: Air cooled 2-stroke
Induction system eed valve
Displacement 49.0 cm3(2.99 cu.in)
Cylinder arrangement Forward-inclined single cylinder
Bore x stroke 40.0 x 39.2 mm (1.57 x 1.54 in)
Compression ratio 6.00 :1
Starting system Kickstarter
Fuel:
ecommended fuel egular unleaded gasoline only
(For CANADA, EU OPE)
Unleaded gasoline only (Except for CANADA,EU OPE)
Fuel tank capacity 2.0 L (0.53 US gal) (0.44 Imp.gal)
Engine oil:
Lubrication system Separate lubrication (Yamaha autolube)
Type YAMALUBE 2 or 2-stroke engine oil
Engine oil quantity
Quantity 0.30 L (0.32 US qt) (0.26 Imp.qt)
Transmission oil:
Type YAMALUBE 4 (10W30) or SAE 10W30
(Except for EU OPE)
SAE 10W30 (For EU OPE)
API service SG type or higher
JASO standard MA
Total amount 0.35 L (0.37 US qt) (0.31 Imp.qt)
Oil change quantity 0.30 L (0.32 US qt) (0.26 Imp.qt)
Autolube pump:
Plunger diameter 3.50 mm (0.14 in)
Color code YELLOW
Minimum stroke 0.25-0.30 mm (0.010-0.012 in)
Maximum stroke 1.00-1.15 mm (0.04-0.05 in)
Minimum output/200 strokes 0.48-0.57 cm3(0.03-0.04 cu.in)
Pulley adjusting mark At idle
Spark plug (s):
Manufacturer/model NGK/BP4HS (Except for CANADA,EU OPE)
NGK/BP 4HS (For CANADA, EU OPE)
DENSO/W14FPL (Except for CANADA,EU OPE)
Spark plug gap 0.6-0.7 mm (0.024-0.028 in)
SPEC
MAINTENANCE SPECIFICATIONS
2-2
MAINTENANCE SPECIFICATIONS
ENGINE
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SPEC
MAINTENANCE SPECIFICATIONS
2-3
Item PW50
Cylinder head:
Volume 6.80 cm3(0.41 cu.in)
Warpage limit 0.03 mm (0.0012 in)
Cylinder:
Bore 39.993-40.012 mm (1.5745-1.5753 in)
Wear limit 40.100 mm (1.5787 in)
Taper limit 0.050 mm (0.0020 in)
Out of round limit 0.010 mm (0.0004 in)
Piston:
Piston-to-cylinder clearance 0.034-0.047 mm (0.0013-0.0019 in)
Limit 0.10 mm (0.0039 in)
Diameter D 39.952-39.972 mm (1.5729-1.5737 in)
Height H 5.0 mm (0.20 in)
Offset 0.20 mm (0.0079 in)
Offset direction Exhaust side
Piston pin bore inside diameter 10.004-10.015 mm (0.3939-0.3943 in)
Limit 10.035 mm (0.3951 in)
Piston pin outside diameter 9.994-10.000 mm (0.3935-0.3937 in)
Limit 9.974 mm (0.3927 in)
Piston ring:
Top ring
ing type Keystone
Dimensions (B x T) 1.50 x 1.80 mm (0.06 x 0.07 in)
End gap (installed) 0.15-0.35 mm (0.0059-0.0138 in)
Limit 0.50 mm (0.0197 in)
ing side clearance 0.020-0.060 mm (0.0008-0.0024 in)
Limit 0.080 mm (0.0032 in)
2nd ring
ing type Keystone
Dimensions (B x T) 1.50 x 1.80 mm (0.06 x 0.07 in)
End gap (installed) 0.15-0.35 mm (0.0059-0.0138 in)
Limit 0.50 mm (0.0197 in)
ing side clearance 0.020-0.060 mm (0.0008-0.0024 in)
Limit 0.080 mm (0.0032 in)
Crankshaft:
Width A 37.90-37.95 mm (1.492-1.494 in)
unout limit C 0.050 mm (0.0020 in)
Big end side clearance D 0.350-0.550 mm (0.0138-0.0217 in)
Big end radial clearance 0.350-0.550 mm (0.0138-0.0217 in)
Small end free play F 0.40-0.80 mm (0.02-0.03 in)
H
D
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SPEC
MAINTENANCE SPECIFICATIONS
2-4
Item PW50
Automatic centrifugal clutch:
Clutch type Wet, centrifugal automatic
Clutch housing inside diameter 105 mm (4.13 in)
Wear limit 106 mm (4.17 in)
Clutch shoe thickness 1.0 mm (0.04 in)
Wear limit 0.7 mm (0.03 in)
Clutch shoe spring free length 34.5 mm (1.36 in)
Llimit 35.5 mm (1.40 in)
Clutch-in revolution 2700 r/min
Clutch-stall revolution 3500 r/min
Transmission:
Primary reduction system Spur gear
Primary reduction ratio 63/33 (1.909)
Secondary reduction system Shaft drive
Secondary reduction ratio 19/15 x 54/11 (6.218)
Kickstarter:
Kickstarter type atchet
Kick clip friction force P 1-5 N (0.34-1.33 lbf) (0.15-0.60 kgf)
Air filter:
Air filter oil grade Foam air-filter oil or SAE10W30SE
Carburetor:
Type x quantity VM12SC x 1
Manufacturer MIKUNI
ID mark 5PG1 10
Main jet #70
Air jet 2.5
Jet needle 3X24-1
Needle jet E-2
Pilot outlet 0.9
Pilot jet #40
Valve seat size 1.2
Starter jet 1 #30
Float height 15.5-17.5 mm (0.61-0.69 in)
Fuel level (using fuel level gauge) 2.0-4.0 mm (0.08-0.16 in)
Idling condition:
Engine idling speed 1650-1750 r/min
Throttle cable free play: 1.5-3.5 mm (0.06-0.14 in)
eed valve:
Thickness T 0.200 mm (0.0079 in)
Valve stopper height 4.6-5.0 mm (0.18-0.20 in)
Llimit 7.4-7.8 mm (0.291-0.307 in)
Valve bending limit 0.2 mm (0.01 in)
T
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