Yamaha YFM45FAR User manual

YFM45FAR
YFM450FAR
5ND2-AE1
SERVICE MANUAL

YFM45FAR/YFM450FAR
SERVICE MANUAL
©2002 by Yamaha Motor Co., Ltd.
First edition, March 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
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.
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
damage 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
accompanied 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 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

TABLE OF CONTENTS
GENERAL INFORMATION GEN
INFO 1
SPECIFICATIONS SPEC 2
PERIODIC CHECKS AND
ADJUSTMENTS CHK
ADJ 3
ENGINE ENG 4
COOLING SYSTEM COOL 5
CARBURETION CARB 6
DRIVE TRAIN DRIV 7
CHASSIS CHAS 8
ELECTRICAL ELEC 9
TROUBLESHOOTING TRBL
SHTG
10
–+

GEN
INFO 1

GEN
INFO
CHAPTER 1.
GENERAL INFORMATION
MACHINE IDENTIFICATION ........................................................................ 1-1
VEHICLE IDENTIFICATION NUMBER ................................................. 1-1
MODEL LABEL ..................................................................................... 1-1
FEATURES ................................................................................................... 1-2
LIQUID COOLING ENGINE .................................................................. 1-2
PARK POSITION .................................................................................. 1-2
FRONT DIFFERENTIAL ....................................................................... 1-3
IMPORTANT INFORMATION ...................................................................... 1-8
PREPARATION FOR REMOVAL PROCEDURES ............................... 1-8
REPLACEMENT PARTS ...................................................................... 1-8
GASKETS, OIL SEALS AND O-RINGS ................................................ 1-8
LOCK WASHERS/PLATES AND COTTER PINS ................................. 1-9
BEARINGS AND OIL SEALS ................................................................ 1-9
CIRCLIPS .............................................................................................. 1-9
CHECKING OF CONNECTIONS ............................................................... 1-10
SPECIAL TOOLS ....................................................................................... 1-11

GEN
INFO

1 - 1
GEN
INFO
MACHINE IDENTIFICATION
GENERAL INFORMATION
MACHINE IDENTIFICATION
VEHICLE IDENTIFICATION NUMBER
The vehicle identification number 1is
stamped into the left side of the frame.
MODEL LABEL
The model label 1is affixed to the frame. This
information will be needed to order spare
parts.

1 - 2
GEN
INFO
FEATURES
LIQUID COOLING ENGINE
Compact liquid cooled 45°inclined engine. A
liquid cooling system has been incorporated
for stable power and engine endurance.
1Radiator
2Thermo switch
3Fan motor
PARK POSITION
When the drive select lever is shifted into the
park position, a stopper lever is engaged into
the stopper gear preventing the drive select
lever and transmission from moving.
When the drive select lever is at the “L”, “H”,
“N”, or “R”positions, the stopper lever end 1
is moved away from the stopper gear 2by the
return spring 3.
When the drive select lever is in the “P”
position, the lever cam 4at the side of the
shift cam 5lifts the stopper lever end 6and
the stopper lever end locks the drive axle 7.
When the stopper lever end 1is not
synchronized, a torsion spring 8retains the
rotation force of the shift cam 5until it is
synchronized.
FEATURES

GEN
INFO
1 - 3
FEATURES
FRONT DIFFERENTIAL
1Adapter
2Drive clutch
3Differential side gear (left)
4Differential pinion gear
5Ring gear
6Differential side gear (right)
7Drive pinion gear
8Gear motor
ÈTo front wheel
ÉFrom the middle gear

GEN
INFO
1 - 4
FEATURES
2WD
Power is transmitted as follows: middle gear →front drive shaft →drive pinion gear 7→ring gear
5→differential pinion gear 4. In the 2WD mode, the left differential side gear 3and the drive
clutch 2are not engaged, therefore, the left side gear runs idle and does not transmit power to the
left front constant velocity joint.

GEN
INFO
1 - 5
FEATURES
4WD
When the 4WD mode is selected, the gear motor is operated, and the drive clutch 2moves to the
right and engages with the left differential side gear 3. Accordingly, power is transmitted as follows:
ring gear 5→differential pinion gear 4→left differential side gear 3→drive clutch 2→adapter
1→left front constant velocity joint.
Meanwhile, power from the differential pinion gear 4is transmitted to the right front constant
velocity joint via the right differential side gear 6.
The ring gear 5and the drive clutch 2are not engaged at this time. Therefore, the rotational
difference that occurs between the right and left wheels, while the handlebar is being turned, is
absorbed by the difference in the rotational speeds of the ring gear 5and the left differential side
gear 3.

GEN
INFO
1 - 6
FEATURES
4WD (Diff-Lock)
When the 4WD (Diff-Lock) mode is selected, the gear motor moves the drive clutch 2further to the
right, which causes the ring gear 5and the drive clutch 2to engage. As a result, power is
transmitted directly from the ring gear 5to the drive clutch 2, then to the left front constant velocity
joint via the adapter 1.
Meanwhile, because the ring gear 5and the drive clutch 2are engaged, the ring gear 5, the drive
clutch 2, and the right differential side gear 6become locked coaxially. Thus, power is transmitted
as follows: differential pinion gear 4→right differential pinion gear 6→right front constant
velocity joint.
When the ATV is in the 4WD (Diff-Lock) mode, the right and left wheels rotate constantly at the
same speed, which affects the maneuverability of the ATV (e.g., making it difficult to steer).
Therefore, the maximum traveling speed is limited to 35 km/h (22 mph).

GEN
INFO
1 - 7
FEATURES
In addition, the 4WD (Diff-Lock) mode can be engaged only when the ATV is stopped. Even if an
attempt is made to select this mode when the ATV is traveling, it will only result in a standby
condition (i.e., when the differential lock select switch and the differential gear are not matched).
(1) When the ATV is traveling
Even if the 4WD (Diff-Lock) mode is selected, the gear motor will stand by, instead of operating.
Therefore, the ATV can be driven in the normal 4WD mode. When this occurs, the differential gear
lock indicator light “”in the speedometer unit will flash to alert the driver that the control is on
standby. When the ATV is stopped, the control transfers to the condition described in (2).
(2) When the ATV is stopped
The gear motor operates to connect the drive clutch to the differential case, thus resulting in the
differential lock condition. When this occurs, the differential gear lock indicator light “”in the
speedometer unit changes to a constant illumination.
* Until the drive clutch and the differential case mesh together (i.e., the splines are unmeshed) the
engine misfires to control the engine speed. During this time, the differential gear lock indicator light
in the speedometer unit continues to flash.
DIFF.
LOCK
DIFF.
LOCK

1 - 8
GEN
INFO
EB101000
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL
PROCEDURES
1.Remove all dirt, mud, dust and foreign
material before removal and disassembly.
2.Use proper tools and cleaning equipment.
Refer to the “SPECIAL TOOLS”section.
3.When disassembling the machine, always
keep mated parts together. This includes
gears, cylinder, piston and other parts that
have been “mated”through normal wear.
Mated parts must always be reused or
replaced as an assembly.
4.During machine disassembly, clean all 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.
EB101010
REPLACEMENT PARTS
1.Use only genuine Yamaha parts for all
replacements. Use oil and grease
recommended by Yamaha for all lubrication
jobs. Other brands may be similar in function
and appearance, but inferior in quality.
EB101020
GASKETS, OIL SEALS AND O-RINGS
1.Replace all gaskets, seals and O-rings when
overhauling the engine. All gasket surfaces,
oil seal lips and O-rings must be cleaned.
2.Properly oil all mating parts and bearings
during reassembly. Apply grease to the oil
seal lips.
IMPORTANT INFORMATION

1 - 9
GEN
INFO
EB101030
LOCK WASHERS/PLATES AND COTTER
PINS
1.Replace all lock washers/plates 1and cotter
pins after removal. Bend lock tabs along the
bolt or nut flats after the bolt or nut has been
tightened to specification.
EB101040
BEARINGS AND OIL SEALS
1.Install bearings and oil seals so that the
manufacturer’s marks or numbers are visible.
When installing oil seals, apply a light
coating of lightweight lithium base grease to
the seal lips. Oil bearings liberally when
installing, if appropriate.
1Oil seal
CAUTION:
Do not use compressed air to spin the
bearings dry. This will damage the bearing
surfaces.
1Bearing
EB101050
CIRCLIPS
1.Check all circlips carefully before
reassembly. Always replace piston pin clips
after one use. Replace distorted circlips.
When installing a circlip 1, make sure that
the sharp-edged corner 2is positioned
opposite the thrust 3it receives. See
sectional view.
4Shaft
IMPORTANT INFORMATION