Yamaha YFM660FR Manual

YFM660FR
5KM2-AE2
SUPPLEMENTARY
SERVICE MANUAL

FOREWORD
This Supplementary Service Manual has been prepared to introduce new service and data for the
YFM660FR. For complete service information procedures it is necessary to use this Supplementary
Service Manual together with the following manual.
YFM660F(P) 2002 SERVICE MANUAL: 5KM2-AE1
YFM660FR
SUPPLEMENTARY
SERVICE MANUAL
©2002 by Yamaha Motor Co., Ltd.
First edition, June 2002
All rights reserved.
Any reproduction or unauthorized use
without the written permission of
Yamaha Motor Co., Ltd.
is expressly prohibited.

EB001000
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.
N
OTE:
Designs and specifications are subject to change without notice.
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 inspecting 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:

EB002000
HOW TO USE THIS MANUAL
MANUAL ORGANIZATION
This manual consists of chapters for the main categories of subjects. (See “Illustrated 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 0are printed on the
top right of each page and indicate the subject
of each chapter.
1General information
2Specifications
3Periodic checks and adjustments
4Engine
5Cooling system
6Carburetion
7Drive train
8Chassis
9Electrical
0Troubleshooting
Illustrated symbols Ato Hare used to identify
the specifications appearing in the text.
ACan be serviced with engine mounted
BFilling fluid
CLubricant
DSpecial tool
ETorque
FWear limit, clearance
GEngine speed
HΩ, V, A
Illustrated symbols Ito Nin the exploded
diagrams indicate the types of lubricants and
lubrication points.
IApply engine oil
JApply gear oil
KApply molybdenum disulfide oil
LApply wheel bearing grease
MApply lightweight lithium-soap-based grease
NApply molybdenum disulfide grease
Illustrated symbols Oto Pin the exploded
diagrams indicate where to apply a locking
agent Oand when to install a new part P.
OApply the locking agent (LOCTITE)
PReplace
12
34
56
78
90
AB
CD
EF
GH
IJK
LMN
OP
GEN
INFO SPEC
CHK
ADJ ENG
COOL CARB
DRIV
CHAS
–+
ELEC TRBL
SHTG
T
R
.
.
EGM
BLS M
LT New

CONTENTS
GENERAL INFORMATION ..............................................................................1
SPECIAL TOOLS ......................................................................................1
SPECIFICATIONS ............................................................................................2
GENERAL SPECIFICATIONS ..................................................................2
MAINTENANCE SPECIFICATIONS .........................................................3
ENGINE ................................................................................................3
ELECTRICAL ........................................................................................3
TIGHTENING TORQUES .........................................................................4
CABLE ROUTING .....................................................................................5
PERIODIC CHECKS AND ADJUSTMENTS ..................................................12
INTRODUCTION .....................................................................................12
PERIODIC MAINTENANCE/LUBRICATION ...........................................12
SEAT, CARRIERS, FENDERS AND FUEL TANK ..................................14
FRONT CARRIER, FRONT BUMPER AND FRONT GRILL ..............14
FUEL TANK ........................................................................................15
FOOTREST BOARDS .............................................................................17
ENGINE ...................................................................................................18
CHECKING THE STARTER CABLE ..................................................18
ENGINE ..........................................................................................................19
CAMSHAFT AND CYLINDER HEAD ......................................................19
RECOIL STARTER AND AC MAGNETO ...............................................21
CHECKING THE STARTER CLUTCH ................................................23
MIDDLE GEAR ........................................................................................24
MIDDLE DRIVEN SHAFT ...................................................................24
REMOVING THE MIDDLE DRIVEN SHAFT ......................................26
INSTALLING THE MIDDLE DRIVEN SHAFT .....................................28
DRIVE TRAIN .................................................................................................30
FRONT CONSTANT VELOCITY JOINTS
AND DIFFERENTIAL GEAR ...............................................................30
DISASSEMBLING THE DIFFERENTIAL GEAR .................................34
CHECKING THE DIFFERENTIAL GEAR ...........................................34
ASSEMBLING THE DIFFERENTIAL GEAR .......................................35

CHASSIS ........................................................................................................37
FRONT WHEELS AND BRAKE DISCS ..................................................37
FRONT WHEELS ................................................................................37
REAR WHEELS AND BRAKE DISC .......................................................39
REAR WHEELS ..................................................................................39
STEERING SYSTEM ..............................................................................40
TIE ROD AND STEERING KNUCKLE ................................................40
CHECKING THE STEERING KNUCKLE ............................................42
REAR KNUCKLE AND STABILIZER ......................................................43
CHECKING THE REAR KNUCKLE ....................................................44
REAR ARMS AND REAR SHOCK ABSORBER .....................................45

GEN
INFO
–1 –
SPECIAL TOOLS
GENERAL INFORMATION
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
90890-01486
YM-01486
Coupling gear holding tool
This tool is needed when removing or
installing the coupling gear nut.

–2 –
SPEC
SPECIFICATIONS
GENERAL SPECIFICATIONS
Item Standard
Model code: 5KM9: (for CDN)
5KMB: (for Europe)
5KMC: (for Oceania)
Bulb wattage ×quantity:
Headlight 12 V 30 W/30 W ×2
Tail/brake light 12 V 5 W/21 W ×1
Indicator lights
Neutral LED ×1
Fuel LCD ×1
Reverse LED ×1
Coolant temperature warning LED ×1
Park position LED ×1
High gear LED ×1
Low gear LED ×1
Diff-lock LED ×1
GENERAL SPECIFICATIONS

–3 –
SPEC
MAINTENANCE SPECIFICATIONS
ENGINE
ELECTRICAL
Item Standard Limit
Oil pump:
Oil filter type Foam ----
Oil pump type Trochoid ----
Tip clearance “A”or “B”0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)
0.15 mm
(0.006 in)
Side clearance 0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)
0.17 mm
(0.007 in)
Bypass valve setting pressure 441 ~ 637 kPa (4.41 ~
6.37 kg/cm2, 62.7 ~ 90.6 psi)
----
Oil pressure (hot) 65 kPa (0.65 kg/cm2, 9.2 psi) at
1,500 r/min
----
Pressure check location Cylinder head ----
Item Standard Limit
C.D.I.:
Magneto model/manufacturer F4T46972/MITSUBISHI ----
Pickup coil resistance/color 459 ~ 561 Ωat 20 °C (68 °F)/
White/Red –White/Green
----
Rotor rotation direction sensing coil resis-
tance/color
0.063 ~ 0.077 Ωat 20 °C (68 °F)/
Red –White/Blue
----
C.D.I. unit model/manufacturer F8T38671/MITSUBISHI ----
Charging system:
Type A.C. magneto generator ----
Model/manufacturer F4T469/MITSUBISHI ----
Nominal output 14 V 21 A at 5,000 r/min ----
Charging coil resistance/color 0.32 ~ 0.43 Ωat 20 °C (68 °F)/
White –White
----
MAINTENANCE SPECIFICATIONS

–4 –
SPEC
TIGHTENING TORQUES
Engine tightening torques
Chassis tightening torques
Part to be tightened Part
name
Thread
size Q’ty Tightening torque Remarks
Nm m·kg ft·lb
Exhaust pipe protector Bolt M6 5 11 1.1 8
Oil seal retainer Screw M5 2 7 0.7 5.1
Part to be tightened Thread size Tightening torque Remarks
Nm m·kg ft·lb
Front wheel hub and constant velocity joint M20 260 26.0 190 Stake
Rear wheel hub and constant velocity joint M20 260 26.0 190 Stake
Front brake master cylinder and handlebar M8 7 0.7 5.1 LT
TIGHTENING TORQUES

–5 –
SPEC
CABLE ROUTING
1Fuel sender lead
2Differential gear case and final
drive gear case breather hose
3Vacuum chamber breather hose
4Starter motor lead
5Wire harness
6Gear position switch lead
7Final drive gear case breather
hose
8Ground lead
9Speed sensor lead
0AC magneto lead
ACarburetor breather hose
BStarter cable
CFuel hose
DThermo switch 1 lead
EReverse switch lead
FAC magneto coupler
GGear position switch coupler
HSpeed sensor coupler
IRadiator fan breather hose
JRectifier/regulator lead
KWater pump breather hose
B - B
A
C D
AB
B
4
3
2
1
98
Ë
Ê
É
È
5
C
6
7
0
A
7
J
2
I
F
HG
D
E8
C
B
D
Í
E
E
D
K
E - E
Ï
3Î
Ì
7
I5
CABLE ROUTING

–6 –
SPEC
ÈFasten the final drive gear case breather hose, speed sensor lead, ground lead, gear position switch lead,
AC magneto lead, wire harness, and reverse indicator light lead with a plastic locking tie. Be careful not to
pinch the breather hose.
ÉFasten the leads in the following order: ground lead, reverse switch lead, speed sensor lead, gear position
switch lead, and AC magneto lead.
ÊPass the final drive gear case breather hose through the hole in air duct assembly 3.
ËTo the rear fender
Ì70 ~ 90 mm (2.8 ~ 3.5 in)
ÍClamp the thermostat assembly breather hose and carburetor breather hose with the cable guide.
B - B
A
C D
AB
B
4
3
2
1
98
Ë
Ê
É
È
5
C
6
7
0
A
7
J
2
I
F
HG
D
E8
C
B
D
Í
E
E
D
K
E - E
Ï
3Î
Ì
7
I5
CABLE ROUTING

–7 –
SPEC
ÎPass the vacuum chamber breather hose through the plastic cover hole.
ÏInsert a hook into the third hole from the bottom of the rectifier/regulator bracket, and then fasten the final
drive gear case breather hose onto the hook.
B - B
A
C D
AB
B
4
3
2
1
98
Ë
Ê
É
È
5
C
6
7
0
A
7
J
2
I
F
HG
D
E8
C
B
D
Í
E
E
D
K
E - E
Ï
3Î
Ì
7
I5
CABLE ROUTING

–8 –
SPEC
1Gear position switch
2Reverse switch
3Crankcase breather hose
4Select lever control cable
5Rear brake cable
6Front brake hose
7Rear brake light switch lead
8Spark plug lead
9Fan motor breather hose
0Fan motor lead
ABrake fluid reservoir hose
BRear brake hose
ÈPass the rear brake cable and throttle cable
through the cable guide.
ÉPass the rear brake light switch lead, main switch
lead and auxiliary DC jack lead over the front
fender.
BA
0
9
8
7
6
5
4
3
21 È
É
ÊË
Í
Ì
CABLE ROUTING

–9 –
SPEC
ÊClamp the spark plug lead and radiator inlet hose with a plastic clip.
ËWhen installing the ignition coil, face the spark plug lead to the right side of the frame.
ÌTo the rear fender hole
ÍPass the brake light switch lead on the inside of the rear brake cable and select lever control cable, and
through the cable guide of the brake master cylinder cover.
BA
0
9
8
7
6
5
4
3
21 È
É
ÊË
Í
Ì
CABLE ROUTING

–10 –
SPEC
1Front brake hose
2Throttle cable
3Thermo switch 1 lead
4Crankcase breather hose
5Fuel sender lead
6Differential gear case breather hose
7Starter cable
8Select lever control cable
9Wire harness
0Fan motor breather hose
ÈPass the thermo sensor 1 lead through the lead
guide.
ÉPass the crankcase breather hose through the
hose guide.
ÊPass the fuel sender lead through the lead
guide.
ËPass the select lever control cable through the
hole of the select lever unit bracket.
ÌClamp the starter cable with a cable holder.
ÍPass the throttle cable through the cable guide.
CC
B
A - A
B
C - C
0
6
9
4
3
2
1
8
7
6
5
Ê
É
È
Î
Ì
Ë
A
A
8
Í
CABLE ROUTING

–11 –
SPEC
ÎFasten the wire harness speed sensor coupler, thermo switch 1 lead, reverse switch lead, and ground lead
with a plastic locking tie.
CC
B
A - A
B
C - C
0
6
9
4
3
2
1
8
7
6
5
Ê
É
È
Î
Ì
Ë
A
A
8
Í
CABLE ROUTING

–12 –
CHK
ADJ
INTRODUCTION/PERIODIC MAINTENANCE/
LUBRICATION
EB300000
PERIODIC CHECKS AND ADJUSTMENTS
INTRODUCTION
This chapter includes all information necessary to perform recommended inspections and adjust-
ments. These preventive maintenance procedures, if followed, will ensure more reliable vehicle
operation and a longer service life. The need for costly overhaul work will be greatly reduced. This
information applies to vehicles already in service as well as to new vehicles that are being prepared
for sale. All service technicians should be familiar with this entire chapter.
EBU00261
PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINE
INITIAL EVERY
Whichever
comes first
km
(mile)
320
(200)
1,200
(750)
2,400
(1,500)
2,400
(1,500)
4,800
(3,000)
hours 20 75 150 150 300
Valves* •Check valve clearance.
•Adjust if necessary.
Cooling system
•Check coolant leakage.
•Repair if necessary.
•Replace coolant every 24 months.
Spark plug
•Check condition.
•Adjust gap and clean.
•Replace if necessary.
Air filter •Clean.
•Replace if necessary.
Every 20 ~ 40 hours
(More often in wet or dusty areas.)
Carburetor* •Check and adjust idle speed/starter operation.
•Adjust if necessary.
Crankcase breather
system*
•Check breather hose for cracks or damage.
•Replace if necessary.
Exhaust system*
•Check for leakage.
•Retighten if necessary.
•Replace gasket(s) if necessary.
Fuel line* •Check fuel hose for cracks or damage.
•Replace if necessary.
Engine oil •Replace (Warm engine before draining).
Engine oil filter car-
tridge •Replace.
Final gear oil •Check oil level/oil leakage.
•Replace.
Differential gear oil
Front brake* •Check operation/fluid leakage/see NOTE page 13.
•Correct if necessary.
Rear brake* •Check operation/fluid leakage/see NOTE page 13.
•Correct if necessary.
V-belt* •Check operation.
•Check for cracks or damage.
Wheels* •Check balance/damage/runout.
•Repair if necessary.