Yamaha Raptor YFM350S User manual

YFM350S
3GD-AE7
SUPPLEMENTARY
SERVICE MANUAL

FOREWORD
This Supplementary Service Manual has been prepared to introduce new service and data for the
YFM350S. For complete service information procedures it is necessary to use this Supplementary
Service Manual together with the following manual.
YFM350X(J) ’97 SERVICE MANUAL: 3GD-AE5
YFM350X(P) 2002 SUPPLEMENTARY SERVICE MANUAL: 3GD-AE6
YFM350S
SUPPLEMENTARY
SERVICE MANUAL
©2004 by Yamaha Motor Co., Ltd.
First edition, January 2004
All rights reserved.
Any reproduction or unauthorized use
without the written permission of
Yamaha Motor Co., Ltd.
is expressly prohibited.

EBS00002
NOTICE
This manual was produced by the Yamaha Motor Company primarily for use by Yamaha dealers
and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one
manual, so it is assumed that anyone who uses this book to perform maintenance and repairs on
Yamaha machine has a basic understanding of the mechanical ideas and the procedures of
machine repair. Repairs attempted by anyone without this knowledge are likely to render the
machine unsafe and unfit for use.
Yamaha Motor Company, Ltd. is continually striving to improve all its models. Modifications and sig-
nificant 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:
_
Designs and specifications are subject to change without notice.
EBS00003
IMPORTANT INFORMATION
Particularly important information is distinguished in this manual by the following notations.
The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED!
Failure to follow WARNING instructions could result in severe injury or death
to the machine operator, a bystander or a person checking or repairing the
machine.
A CAUTION indicates special precautions that must be taken to avoid dam-
age to the machine.
A NOTE provides key information to make procedures easier or clearer.
WARNING
CAUTION:
NOTE:

EBS00004
HOW TO USE THIS MANUAL
MANUAL ORGANIZATION
This manual consists of chapters for the main categories of subjects. (See “symbols”)
1st title 1: This is the title of the chapter with its symbol in the upper right corner of each page.
2nd title 2: This title indicates the section of the chapter and only appears on the first page of each
section. It is located in the upper left corner of the page.
3rd title 3: This title indicates a sub-section that is followed by step-by-step procedures accompa-
nied by corresponding illustrations.
EXPLODED DIAGRAMS
To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each
removal and disassembly section.
1. An easy-to-see exploded diagram 4is provided for removal and disassembly jobs.
2. Numbers 5are given in the order of the jobs in the exploded diagram. A number that is enclosed
by a circle indicates a disassembly step.
3. An explanation of jobs and notes is presented in an easy-to-read way by the use of symbol marks
6. The meanings of the symbol marks are given on the next page.
4. A job instruction chart 7accompanies the exploded diagram, providing the order of jobs, names
of parts, notes in jobs, etc.
5. For jobs requiring more information, the step-by-step format supplements 8are given in addition
to the exploded diagram and the job instruction chart.

EB003000
ILLUSTRATED SYMBOLS
Illustrated symbols 1to 8are printed on the
top right of each page and indicate the subject
of each chapter.
1General information
2Specifications
3Periodic checks and adjustments
4Engine
5Carburetion
6Chassis
7Electrical
8Troubleshooting
Illustrated symbols 9to Eare used to identify
the specifications appearing in the text.
9Filling fluid
0Lubricant
ASpecial tool
BTorque
CWear limit, clearance
DEngine speed
EΩ, V, A
Illustrated symbols Fto Lin the exploded
diagrams indicate the types of lubricants and
lubrication points.
FApply engine oil
GApply gear oil
HApply molybdenum disulfide oil
IApply wheel bearing grease
JApply lightweight lithium soap base grease
KApply molybdenum disulfide grease
LApply silicon grease
Illustrated symbols Mto Nin the exploded
diagrams indicate where to apply a locking
agent Mand when to install a new part N.
MApply the locking agent (LOCTITE®)
NReplace
12
34
56
78
90
AB
CD
E
FGH
I
MN
GEN
INFO SPEC
CHK
ADJ ENG
CARB CHAS
–+
ELEC TRBL
SHTG
T
R
.
.
EGM
BLS MS
JKL
LT
New

CONTENTS
GENERAL INFORMATION ................................................................................ 1
MACHINE IDENTIFICATION ....................................................................... 1
MODEL LABEL ...................................................................................... 1
SPECIAL TOOLS ......................................................................................... 2
SPECIFICATIONS.............................................................................................. 3
GENERAL SPECIFICATIONS ..................................................................... 3
MAINTENANCE SPECIFICATIONS ............................................................ 5
ENGINE ................................................................................................. 5
CHASSIS ............................................................................................... 7
ELECTRICAL....................................................................................... 10
CABLE ROUTING ...................................................................................... 11
PERIODIC CHECKS AND ADJUSTMENTS.................................................... 23
INTRODUCTION ........................................................................................ 23
PERIODIC MAINTENANCE/LUBRICATION.............................................. 23
SEAT, FENDERS AND FUEL TANK.......................................................... 25
SEAT, SIDE COVERS, AND FRONT PANEL ..................................... 25
FOOT PROTECTORS, ENGINE SKID PLATE,
AND FRONT BUMPER....................................................................... 26
HEADLIGHTS AND FRONT FENDER ................................................ 27
REAR FENDER ................................................................................... 28
FUEL TANK ......................................................................................... 30
CHASSIS.................................................................................................... 32
CHECKING THE FRONT BRAKE PADS............................................. 32
ADJUSTING THE PARKING BRAKE .................................................. 32
ADJUSTING THE REAR SHOCK ABSORBER................................... 33
ELECTRICAL SYSTEM.............................................................................. 35
CHECKING AND CHARGING THE BATTERY ................................... 35
ADJUSTING THE HEADLIGHT BEAMS ............................................. 40
REPLACING A HEADLIGHT BULB..................................................... 41
ENGINE ............................................................................................................ 42
ENGINE REMOVAL ................................................................................... 42
INSTALLING THE ENGINE ................................................................. 42
CLUTCH ..................................................................................................... 43
INSTALLING THE RIGHT CRANKCASE COVER............................... 43
CARBURETOR................................................................................................. 44
CARBURETOR .......................................................................................... 44

CHASSIS .......................................................................................................... 47
REAR WHEELS AND REAR AXLE HUB ................................................... 47
REMOVING THE REAR AXLE ............................................................ 49
INSTALLING THE REAR AXLE........................................................... 50
FRONT ARMS AND FRONT SHOCK ABSORBER ................................... 51
REAR BRAKE ............................................................................................ 53
ASSEMBLING THE REAR BRAKE CALIPER ..................................... 53
REAR SHOCK ABSORBER AND SWINGARM ......................................... 54
HANDLING THE REAR SHOCK ABSORBER
AND GAS CYLINDER......................................................................... 56
DISPOSING OF THE REAR SHOCK ABSORBER
AND GAS CYLINDER......................................................................... 56
ELECTRICAL ................................................................................................... 57
ELECTRICAL COMPONENTS................................................................... 57
YFM350S WIRING DIAGRAM

–1 –
GEN
INFO
GENERAL INFORMATION
MACHINE IDENTIFICATION
MODEL LABEL
The model label 1is affixed to the frame. This
information will be needed to order spare
parts.
MACHINE IDENTIFICATION

–2 –
GEN
INFO
SPECIAL TOOLS
EB102001
SPECIAL TOOLS
The following special tools are necessary for complete and accurate tune-up and assembly. Use
only the appropriate special tools; this will help prevent damage caused by the use of inappropriate
tools or improvised techniques. Special tools may differ by shape and part number from country to
country. In such a case, two types are provided.
When placing an order, refer to the list provided below to avoid any mistakes.
For US and CDN
P/N. YM-, YU-, YS-, YK-, ACC-
Except for US and CDN
P/N. 90890-
Tool No. Tool name/How to use Illustration
90890-01443
YU-33975
Steering nut wrench
This tool is needed to loosen and tighten
the rear shock absorber locknut.
90890-01498
YM-37134
Axle nut wrench (46 mm)
This tool is needed to loosen or tighten
the rear axle nut.

–3 –
SPEC
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model YFM350S
Model code number 5YT1 (For USA and Oceania)
5YT2 (For CDN)
5YT3 (For Europe)
Dimensions
Overall length 1,770 mm (69.7 in)
Overall width 1,095 mm (43.1 in)
Overall height 1,080 mm (42.5 in)
Seat height 820 mm (32.3 in)
Wheelbase 1,210 mm (47.6 in)
Minimum ground clearance 115 mm (4.53 in)
Basic weight
With oil and full fuel tank 180.0 kg (397 lb)
Minimum turning radius 3,100 mm (122 in)
Engine
Engine type Air-cooled 4-stroke, SOHC
Cylinder arrangement Forward-inclined single cylinder
Displacement 349.0 cm3(21.30 cu.in)
Bore ×stroke 83.0 ×64.5 mm (3.27 ×2.54 in)
Compression ratio 9.20 : 1
Compression pressure 850 kPa (8.5 kg/cm2, 120.9 psi) at 350 r/min
Starting system Electric starter
Oil capacity
Engine oil
Periodic oil change 2.50 L (2.20 Imp qt, 2.64 US qt)
With oil filter replacement 2.60 L (2.29 Imp qt, 2.75 US qt)
Total amount 3.20 L (2.82 Imp qt, 3.38 US qt)
Fuel
Type Regular unleaded gasoline only
(For CDN and Europe)
Unleaded gasoline only (For USA and Oceania)
Tank capacity 9.0 L (1.98 Imp gal, 2.38 US gal)
Reserve amount 2.7 L (0.59 Imp gal, 0.71 US gal)
Carburetor
Type/manufacturer BSR36/MIKUNI
GENERAL SPECIFICATIONS

–4 –
SPEC
GENERAL SPECIFICATIONS
Transmission
Primary reduction system Spur gear
Primary reduction ratio 76/24 (3.167)
Secondary reduction system Chain drive
Secondary reduction ratio 38/13 (2.923)
Transmission type Constant mesh, 6-speed forward, 1-speed
reverse
Operation Left foot operation
Gear ratio 1st 36/16 ×20/27 ×29/18 (2.685)
2nd 33/20 ×20/27 ×29/18 (1.969)
3rd 29/23 ×20/27 ×29/18 (1.504)
4th 27/26 ×20/27 ×29/18 (1.239)
5th 25/28 ×20/27 ×29/18 (1.066)
6th 23/29 ×20/27 ×29/18 (0.946)
Reverse 33/16 ×33/10 (6.806)
Chassis
Frame type Steel tube frame
Caster angle 6°
Trail 26.0 mm (1.02 in)
Toe-in (unloaded) 20 ~ 30 mm (0.79 ~ 1.18 in)
Tires
Type Tubeless
Size front AT21 ×7-10
rear AT20 ×10-9
Manufacturer front DUNLOP
rear DUNLOP
Type front KT851B
rear KT877A
Brakes
Front brake type Dual disc brake
operation Right hand operation
Rear brake type Single disc brake
operation Right foot operation
Electrical
Ignition system DC C.D.I.
Generator system A.C. magneto
Battery voltage/capacity 12 V/8.6 Ah
Battery type YTZ10S
Bulb wattage ×quantity
Headlight 12 V 30 W/30 W ×2
Tail/brake light 12 V 5 W/21 W ×1
Neutral indicator light 12 V 1.7 W ×1
Reverse indicator light 12 V 1.7 W ×1
Model YFM350S

–5 –
SPEC
MAINTENANCE SPECIFICATIONS
MAINTENANCE SPECIFICATIONS
ENGINE
Model YFM350S
Rocker arm/rocker arm shaft
Rocker arm inside diameter 11.980 ~ 11.998 mm (0.4717 ~ 0.4724 in)
Rocker arm shaft outside diameter 11.961 ~ 11.971 mm (0.4709 ~ 0.4713 in)
Rocker-arm-to-rocker-arm-shaft clearance 0.009 ~ 0.037 mm (0.0004 ~ 0.0015 in)
Carburetor
I.D. mark 5YT1 00
Main jet (M.J) #142.5
Main air jet (M.A.J) #35
Jet needle (J.N) 5JFC39-2
Needle jet (N.J) P-0M
Pilot jet (P.J) #22.5
Pilot air jet (P.A.J.1) #65
(P.A.J.2) #165
Pilot outlet (P.O) 1
Bypass 1 (B.P.1) 0.8
Bypass 2 (B.P.2) 0.8
Bypass 3 (B.P.3) 0.8
Pilot screw turns out (P.S) 2-1/4 (For CDN, Europe, and Oceania)
Valve seat (V.S) 2.5
Starter jet (G.S) #70
Throttle valve size (Th.V) #105
Fuel level (F.L) 4 ~ 5 mm (0.16 ~ 0.20 in)
Above the float chamber mating surface
Float height 13.0 mm (0.51 in)
Engine idling speed 1,450 ~ 1,550 r/min
Intake vacuum 33.3 kPa (250 mmHg, 9.83 inHg)

–6 –
SPEC
MAINTENANCE SPECIFICATIONS
Tightening torques
Part to be tightened Part name Thread
size Q’ty Tightening torque Remarks
Nm m ·kg ft ·lb
Carburetor joint Bolt M8 2 20 2.0 14
Carburetor clamp (cylinder head side) Screw M4 1 3 0.3 2.2
Carburetor clamp (air filter case side) Screw M4 1 3 0.3 2.2
Air filter case Screw M4 1 3 0.3 2.2
Muffler and exhaust pipe Bolt M8 1 16 1.6 11
Muffler Bolt M8 2 34 3.4 24
Clutch cable holder Bolt M8 1 16 1.6 11
Right crankcase cover Bolt M6 15 10 1.0 7.2
Left crankcase cover Bolt M6 9 11 1.1 8.0
Crankshaft end cover Bolt M6 4 7 0.7 5.1
Bearing retainer (balancer shaft) Screw M6 2 7 0.7 5.1
Bearing retainer (main axle) Screw M6 2 7 0.7 5.1
Bearing retainer (left crankcase) Screw M5 2 7 0.7 5.1
Drive sprocket Nut M20 1 90 9.0 65 Use a lock
washer.
Stopper lever Bolt M6 1 10 1.0 7.2
Reverse shift cam stopper bolt Bolt M14 1 18 1.8 13
Drive select lever assembly Bolt M8 2 20 2.0 14
Drive select lever shift rod and
reverse shift cam Bolt M6 1 16 1.6 11
Shift rod (shift pedal) locknut Nut M6 2 8 0.8 5.8

–7 –
SPEC
MAINTENANCE SPECIFICATIONS
CHASSIS
Model YFM350S
Steering system
Lock-to-lock angle
Left 42.5°
Right 42.5°
Front suspension
Shock absorber stroke 90.0 mm (3.54 in)
Shock absorber spring free length 232.5 mm (9.15 in)
Spring rate (K1) 32.00 N/mm (3.26 kg/mm, 182.72 lb/in)
(K2) 45.00 N/mm (4.59 kg/mm, 256.95 lb/in)
Spring stroke (K1) 0 ~ 45.0 mm (0 ~ 1.77 in)
(K2) 45.0 ~ 90.0 mm (1.77 ~ 3.54 in)
Optional spring No
Rear suspension
Shock absorber stroke 88.0 mm (3.46 in)
Shock absorber spring free length 238.5 mm (9.39 in)
Spring rate (K1) 57.00 N/mm (5.81 kg/mm, 325.46 lb/in)
Stroke 0 ~ 88.0 mm (0 ~ 3.46 in)
Enclosed gas pressure (standard) 1,500 kPa (15.0 kg/cm2, 213.3 psi)
(Min) 1,450 kPa (14.5 kg/cm2, 206.2 psi)
(Max) 1,550 kPa (15.5 kg/cm2, 220.4 psi)
Wheel
Front wheel type Panel wheel
Rear wheel type Panel wheel
Front rim size/material 10 ×5.5 AT/Aluminum
Rear rim size/material 9 ×8.5 AT/Aluminum
Rim runout limit
Vertical <2.0 mm (0.08 in)>
Lateral <2.0 mm (0.08 in)>
Front disc brake
Type Dual disc brake
Disc outside diameter ×thickness 161.0 ×3.5 mm (6.34 ×0.14 in)
<Limit> <3.0 mm (0.12 in)>
Pad thickness 4.2 mm (0.17 in)
<Limit> <1.0 mm (0.04 in)>
Rear disc brake
Type Single disc brake
Disc outside diameter ×thickness 200.0 ×3.6 mm (7.87 ×0.14 in)
<Limit> <3.1 mm (0.12 in)>
Pad thickness 4.5 mm (0.18 in)
<Limit> <1.0 mm (0.04 in)>

–8 –
SPEC
MAINTENANCE SPECIFICATIONS
Tightening torques
Brake lever and brake pedal
Brake lever free play 0 mm (0 in)
Brake pedal position 50.2 mm (1.98 in)
From the top of the frame to the top of the brake
pedal
Throttle lever free play 2 ~ 4 mm (0.08 ~ 0.16 in)
Drive chain
Type/manufacturer DID520V/DAIDO
Number of links 97 + 1 links
Chain free play 25.0 ~ 35.0 mm (0.98 ~ 1.38 in)
Part to be tightened Thread size Tightening torque Remarks
Nm m ·kg ft ·lb
Engine and frame M10 73 7.3 53
Front shock absorber and frame M10 48 4.8 35
Front shock absorber and lower arm M10 48 4.8 35
Steering knuckle and front wheel hub M14 70 7.0 50
Steering shaft and frame M10 35 3.5 25
Tie-rod locknut M10 15 1.5 11
Disc cover (inner) M6 7 0.7 5.1
Front brake master cylinder M6 7 0.7 5.1
Clutch and parking brake lever assembly M5 4 0.4 2.9
Front brake hose and upper front arm M6 7 0.7 5.1
Front brake pipe and brake pipe joint M10 19 1.9 13
Brake pipe joint and frame M6 10 1.0 7.2
Brake caliper bleed screw M8 6 0.6 4.3
Rear brake hose union bolt M10 28 2.8 20
Parking brake adjusting bolt and locknut M8 16 1.6 11
Rear brake light switch bracket and frame M6 7 0.7 5.1
Rear brake master cylinder and frame M8 23 2.3 17
Rear brake fluid reservoir and frame M6 7 0.7 5.1
Rear brake hose and swingarm M6 7 0.7 5.1
Rear hub and rear brake caliper M8 34 3.4 24
Rear axle ring nut M33 160 16.0 115 LT
Rear axle ring nut set bolt M6 7 0.7 5.1 LT
Rear hub and swingarm (lower) M10 73 7.3 53
Rear shock absorber and frame M12 80 8.0 58
Relay arm and swingarm M12 73 7.3 53
Rear shock absorber and relay arm M12 73 7.3 53
Connecting rod and relay arm M12 73 7.3 53
Connecting rod and frame M12 73 7.3 53
Spring preload adjusting locknut (rear shock
absorber) M44 42 4.2 30
Model YFM350S

–9 –
SPEC
MAINTENANCE SPECIFICATIONS
Swingarm guard and swingarm M8 16 1.6 11
Driven chain sprocket and boss M10 55 5.5 40
Front bumper M8 12 1.2 8.7
Rear bumper M8 34 3.4 24
Drive chain guard M8 12 1.2 8.7
Foot protectors (left and right) and frame M8 16 1.6 11
Foot protectors (left and right), rear fender stay
and frame M8 17 1.7 12
Foot protectors (left and right) and footrest M8 17 1.7 12
Footrest and frame M10 73 7.3 53
Battery holder M6 10 1.0 7.2
Front fender and front fender bracket M6 7 0.7 5.1
Front fender and frame M6 7 0.7 5.1
Front fender bracket (center) and frame M6 10 1.0 7.2
Front fender brackets (left and right) and frame M6 13 1.3 9.4
Headlight bracket and front fender bracket M6 7 0.7 5.1
Rear fender and frame M6 10 1.0 7.2
Rear fender and rear bumper M6 7 0.7 5.1
Rear fender and rear fender stay M6 7 0.7 5.1
Rear fender stay and frame M6 7 0.7 5.1
Rear fender stay and frame M8 16 1.6 11
Engine skid plate and frame M8 12 1.2 8.7
Fuel tank M6 7 0.7 5.1
Fuel cock and fuel tank M6 4 0.4 2.9
Rectifier/regulator M6 7 0.7 5.1
Tail/brake light bracket and rear fender M6 4 0.4 2.9
Part to be tightened Thread size Tightening torque Remarks
Nm m ·kg ft ·lb

–10 –
SPEC
MAINTENANCE SPECIFICATIONS
ELECTRICAL
Model YFM350S
C.D.I.
Magneto model/manufacturer F4T466/MITSUBISHI
Pickup coil resistance 459 ~ 561 Ωat 20 °C (68 °F)
(Color) (White/Red-White/Green)
Rotor rotation direction detection coil resis-
tance
0.083 ~ 0.101 Ωat 20 °C (68 °F)
(Color) (Red-White/Blue)
C.D.I. unit-model/manufacturer F8T40374/MITSUBISHI
Rectifier/regulator
Regulator type Semi conductor-short circuit
Model/manufacturer SH640E-11/SHINDENGEN
No-load regulated voltage 14.1 ~ 14.9 V
Rectifier capacity 14 A
Withstand voltage 200 V
Starter relay
Model/manufacturer 2768095-A/JIDECO
Amperage rating 180 A
Coil winding resistance 4.18 ~ 4.62 Ω
Battery
Specific gravity 1.310 at 20 °C (68 °F)
Starter motor
Model/manufacturer DBQD5/DENSO
Output 0.7 kW
Armature coil resistance 0.0118 ~ 0.0133 Ωat 20 °C (68 °F)
Brush overall length 12 mm (0.47 in)
8.5 mm (0.33 in)
Brush spring pressure 6.38 ~ 9.32 N (651 ~ 950 gf, 22.96 ~ 33.55 oz)
Commutator diameter 28 mm (1.10 in)
27 mm (1.06 in)
Mica undercut 0.6 mm (0.024 in)

–11 –
SPEC
CABLE ROUTING
CABLE ROUTING
1Clutch switch lead
2Starter cable
3Clutch cable
4Parking brake cable
5Front brake hose
6Front brake light switch lead
7Throttle cable
8Neutral indicator light
9Reverse indicator light
0Handlebar switch lead
ÈFasten the front brake light switch lead with two
plastic bands.
ÉFasten the starter cable, clutch switch lead, and
handlebar switch lead with a plastic band.
ÊFasten the clutch switch lead and handlebar
switch lead with a plastic band.
6
5
70
134
8È 9
2
ÉÊ

–12 –
SPEC
CABLE ROUTING
1Parking brake cable
2Clutch cable
3Starter cable
4Clutch switch lead
5Handlebar switch lead
6Neutral/reverse indicator light lead
7Rectifier/regulator
8Front brake light switch lead
9Front brake hose
0Throttle cable
ÈPass the clutch switch lead, handlebar switch
lead, neutral/reverse indicator light lead, front
brake light switch lead, and starter cable through
the guide.
ÉFasten the clutch switch lead, handlebar switch
lead, neutral/reverse indicator light lead, and
front brake light switch lead securely with a plas-
tic locking tie.
1
2
3
4
5
6
0
9
8
È
É
Ë
7
Ê