Yamaha XT 600 AC User manual

XT600 AIAC
SERVICE MANUAL
© 1990 by Yamaha Motor Corporation, U.S.A.
1st Edition, January 1990
All rights reserved. Any reprinting or
unauthorized use without the written
permission of Yamaha Motor Corporation,
U.S.A. is expressly prohibited.
Printed in U.S.A.
PIN: L1T-11616-07-43

NOTICE
This manual was written by the Yamaha Motor Company primarily for use by Yamaha dealers and
their qualified mechanics. It is not possible to put an entire mechanic's education into one manual,
so it is assumed that persons using this book to perform maintenance and repairs on Yamaha motor -
cycles have a basic understanding
of the mechanical concepts and procedures inherent in motorcycle
repair technology. Without such knowledge, attempted repairs or service to this model may render
it unfit to use and/or unsafe.
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
motorcycle will operate as designed. If there is any question about a service procedure, it is im-
perative
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 motor-
cycle and to conform with federal environmental quali ty objectives.
Yamaha
Motor Company, Ltd. is continually striving to improve all models manufactured by Yamaha.
Modifications and significant changes in specifications or procedures will be forwarded to all Authorized
Yamaha dealers and will, where applicable, appear in
future editions of this manual.
NOTE: ____________________________________________________________ _
This Service Manual contains information regarding periodic maintenance to the emission control
system for the XT600EA /EAC. Please read this material carefully.
TECHNICAL PUBLICATIONS
SERVICE DIVISION
MOTORCYCLE GROUP
YAMAHA MOTOR CO., LTD.
PARTICULARLY IMPORTANT ANT INFORMATION
This material is distinguished by the following notation .
AWARNING
NOTE:
The Safety Alert Symbol means ATIENTION! BECOME ALERT! YOUR
SAFETY IS
INVOLVED!
Failure to follow WARNING instr u ctions could result in severe injury or
death to the motorcycle operator, a by s tander,or a person inspecting or
repairing the motorcycle.
A CAUTION indicates special precautions that must be taken to avoid
damage to the motorcycle .
A NOTE provides key
information to make procedures easier or clearer.

HOW TO USE THIS MANUAL
CONSTRACTION OF THIS MANUAL
This manual consists of chapters for the main categories of subjects. (See "Illustrated symbols")
This is a chapter with its symbol on the upper right of each page.
1
st title CD :
2nd title @ :
This title appears on the upper of each page on th'8 left of the chapter
symbol. (For the chapter " Periodic inspection and adjustment"" the 3rd
title appears.)
3rd title ® :
This is a final title.
MANUAL FORMAT
All of the procedures in this manual are organized in a sequential, step-by-step format. The infor-
mation has been compiled to provide the mechanic with an easy to read, handy reference that
contains comprehensive explanations of all disassembly, repair, assembly, and inspections.
A set of particularly important procedure @ is placed between a line of asterisks" *" with each
procedure preceded by " • ".
IMPORT ANT FEATURES
• Data and a special tool are framed in a box preceded by a relevant symbol ® .
• An encircled numeral ® indicates a part name, and an encircled alphabetical letter data or an
alignment mark (J) , the others being indicated by an alphabetical letter in a box @ .
• A condition of a faulty component will precede an arrow symbol and the course of action re-
quired the symbol ®.
EXPLODED DIAGRAM
Each chapter provides exploded diagrams before each disassembly section for ease in identif-
ying correct disassembly and assembly procedures .
:=r ~''' I '- I
3
INSPECTION AND RE PAIR
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ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols CD to @ are designed as
thumb tabs to indicate the chapter's number and
content.
CD General information
(2) Specifications
® Periodic inspection and adjustment
@ Engine
@ Carburetion
@ Chassis
(J) Electrical
® Troubleshooting
Illustrated symbols ® to @ are used to identify
the specifications appearing in the text.
® Filling fluid
® Lubricant
@ Special tool
© Tightening
(j) Wear limit, clearance
(j]) Engine speed
@n,V,A
Illustrated symbols @ to @ in the exploded dia-
gram indicate grade of lubricant and location of
lubrication point.
® Apply engine oil
@ Apply gear oil
@ Apply molybdenum disulfide oil
@ Apply wheel bearing grease
@ Apply lightweight lithium-soap base grease
@ Apply molybdenum disulfide grease
@ Apply locking agent (LOCTITE®I

INDEX
GENERAL INFORMATION
~
GEN
INFO
SPECIFICATIONS
jD
SPEC
PERIODIC INSPECTION
AND ADJUSTMENT
ENGINE OVERHAUL
~.
ENG
CARBURETION
CARB
c#::T0
too---
CHAS
CHASSIS
ELECTRICAL
TROUBLESHOOTING

CONTENTS
CHAPTER 1.
GENERAL INFORMATION
MOTORCYCLE IDENTIFICATION . ... . .. ... ..... ... ..... . . ... ... .. . ... . . 1-1
VEHICLE IDENTIFICATION NUMBER ..... . ... .............. . ....... . . 1-1
ENGINE SERIAL NUMBER .. ... . . ... .. . ..... . .. . ... . ... . . . . . . .. . .. .. 1-1
IMPORTANT INFORMATION .. .. . .. .. ..... ... . ... . ..... . ....... .... . . 1-2
PREPARATION FOR REMOVAL AND DiSASSEMBLy ... .. .. .. .... . . .. .. . 1-2
ALL REPLACEMENT PARTS ·. ........... ... ....... .. ... ............. 1-3
GASKETS, OIL SEALS, AND O-RINGS . .. .... ... . . .. ...... .. .. . ...... 1-3
LOCK WASHERS/PLATES AND COTTER PINS . . . . .......... . .. .. . . ... 1-3
BEARINGS AND OIL SEALS. . ...... .. . . . . . . .. .... . .. . . . .... · ·· ····· .1-3
CIRCLIPS . . ... . . . . . . .. . .... . .. .. .. . . .. ... .. .. ....... . .. ... .. . ... ·1-4
SPECIAL TOOLS· ... . .. . . .. . ..... . .. ..... ... .. ... .. . . . . . .. . ..... . ... 1-4
FOR TUNE UP . .. . ... .. . .. . . ...... . ... . . .... . ... .. .. ..... . .. . . .... 1-4
FOR ENGINE SERVICE ...... .. .. .............. .. .......... . ... . .... 1-5
FOR CHASSIS SERVICE. ... .. .. ..... . ..... .. .. . .. . . . ..... . ...... . .. 1-8
FOR ELECTRICAL COMPONENTS. . .... . . ........ .. .. . ............... 1-9
CHAPTER 2.
SPECIFICATIONS
GENERAL SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
MAINTENANCE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-4
ENGINE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-4
CHASSIS .. .. .. .... . .... . ..... ... ... . ....... . . . .... .... . 2-11
ELECTRICAL . .. . ..... . . .. .. .... . .. .... .... . .. . ...... . . . . 2-15
GENERAL TORQUE
SPECIFICATIONS .. . ....... .. . ..... ... .... . 2-17
DEFINITION OF UNITS .... .... ........ . ....... . .. . . .... ..... 2-17
LUBRICATION POINTS AND LUBRICANT TYPE ... ... ..... ....... 2-18
ENGINE ... ....... . .... . ... ... .... . .. ... ..... . . . ... .. . .. 2- 18
CHASSIS . .. . . ........ . ... . . .. .. . ........ . .. . . .. . .. . . ... 2-19
LUBRICATION DIAGRAM .. . . ... . .. . .... .. . . .. .. ... . .. ... . .. . 2-20
CABLE ROUTING .. . ... . ............. . .. . ... .. .. .. . . . . ..... . 2-24
EMISSION HOSE ROUTING (XT600EAC ONLYI .... . .. ........ ... . .. . . . 2-28

CHAPTER 3.
PERIODIC INSPECTION AND ADJUSTMENT
INTRODUCTION . .... .......... . .. .... .. ...... .. ... . ....... . . 3-1
~
GENERAL MAINTENANCE/LUBRICATION . .... .... .................. ... 3-1
t-----
GEN
INFO
SEAT. FUEL TANK AND COVER . ................. . . .. .... .... .. 3-2
REMOVAL ... . ........................................... 3-2
INSTALLATION ....... ..... . ... .. ........ .... . ...... . ..... 3-5
SPEC
ENGINE .. .. .... .. . ......... . ...... . .. ... .... .. .. .. .... .... 3-6
VALVE CLEARANCE ADJURTMENT ............... . . ........ 3-6
CAM CHAIN ADJUSTMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3-9
fi
IDLE SPEED ADJUSTMENT ..... .. ....... ...... . .. .. ... . ... 3-9
t-----
INSP
THROTTLE CABLE FREE PLAY ADJUSTMENT ... . ....... .. .... 3-10
ADJ
SPARK PLUG INSPECTION ... ......... . . ...... ............ 3-11
IGNITION TIMING CHECK ........... .. ...... .. ... ... .. .. . . 3-13
COMPRESSION MEASUREMENT ............................ 3-14
~ ..
1----.....;
ENGINE OIL LEVEL INSPECTION. ...... ............. ..... . .. 3-16
ENGINE OIL REPLACEMENT ... .. ........ ..... ... . . ....... . 3-18
ENG
OIL PRESSURE INSPECTION ....... .. .... .... .. .. .... ..... . 3-22
CLUTCH
ADJUSTMENT .... . ...... . ........ ... . ... .. ...... 3-23
ENGINE OIL TANK STRAINER CLEANING ..................... 3-25 •
1-----
AIR FILTER CLEANING .................................... 3-27
CARBURETOR
JOINT INSPECTION .... ... ....... ............ 3-28
CARB
FUEL LINE INSPECTION ......... . ......... . . .............. 3-29
CRANKCASE
VENTILATION HOSE INSPECTION ........... . ... 3-29
EXHAUST SYSTEM INSPECTION ......................... .. . 3-29
CANISTER INSPECTION (XT600 EAC ONLY) ........................ 3-30
CHAS
CHASSIS . .......... . ..................................... 3-32
FRONT BRAKE ADJUSTMENT . .. ......... . ....... . ......... 3-32
REAR BRAKE ADJUSTMENT ............... . .. ............. 3-32
iii
BRAKE FLUID INSPECTION ................................ 3-33
BRAKE PAD INSPECTION.
..... . . .... . .... .. ........ .. ..... 3- 34
BRAKE LIGHT SWITCH ADJUSTMENT ..... .... . . .... . .. ... .. 3-35
BRAKE HOSE INSPECTION
................................ 3-35
AIR BLEEDING .. ... .. .. ...... .......... .. . .. . .. ... ... ... 3-35
DRIVE CHAIN SLACK ADJUSTMENT .................... . ... 3-36
DRIVE CHAIN LUBRICATION ............................... 3-38

FRONT FORK INSPECTION . ... .... . ... . . .. ..... . ...... . . . . 3-38
STEERING HEAD ADJUSTMENT .... ..... .. ......... ........ 3-39
REAR SHOCK ABSORBER ADJUSTMENT ..... ... .. . .. . . .... . . 3-40
TIRE INSPECTION
... . .. . .. .. ... . .. . . .. . . ..... . .... . . . .... 3-41
WHEEL INSPECTION .. . .... .. . . .. . . ..... . ... .... ..... . ... 3-44
CABLE INSPECTION
AND LUBRICATION . . .... . ...... . . . . . ... 3-44
LEVER AND PEDAL LUBRICATION .. . . .. .. ....... ..... . . . .. . 3-45
SIDESTAND LUBRICATION . ...... ... ...... ... . . . .. . . . .... . 3-45
SWINGARM AND RELAY ARM LUBRICATION . .. .. . . .... . .. .... 3-45
ELECTRICAL. . . . . .. .... .. . .... . .. . . . . ... ... .. . . .... .... . . . .3-46
BATTERY INSPECTION
... . ..... .. .. . . .. . . . . .. ... . ....... . ·3-46
FUSE INSPECTION .... .. .. . .. . ....... .. . .. . . ... ... .. ... .. 3-53
HEADLIGHT BEAM ADJUSTMENT . . . .. .. ..... .... . . ... ..... 3-55
HEADLIGHT BULB REPLACEMENT
.. .. .. .... .. . . .. .. . . . . .... 3-55
CHAPTER 4.
ENGINE OVERHAUL
ENGINE REMOVAL ...... .. ............ .. .... ...... .................... 4-1
ENGINE OIL .. . ........................... . ............ . .. .. .. ...... 4-1
SEAT AND FUEL TANK ................................ .. .......... 4-1
BATTERY LEAD ............ . ... . ......... . . . ....................... 4-1
CARBURETOR . .. ...... . ... . ....... . ... . .. . ........ . .... .. . ......... 4-2
CLUTCH CABLE . ......... . . . .... . ..... . .. . ... . ....... . .. . . ... .... .. 4-2
EXHAUST PI PE ......... .. . . ... ... . . .. ......... .... . .. . .. .. .. .. .... 4-2
STARTER MOTOR .............. .. ........ .. ........................ 4-3
HOSE AND LEAD ..... . . ......... . .... . ......... . .. .. .............. 4-3
DRIVE CHAIN ........ . .. . ... . . ....... .. . . .. ....... . .. .. .. . ......... 4-4
ENGINE PROTECTOR .... ...... ........ .. .. .... .................... 4-4
ENGINE REMOVAL ............ .... .. ........ .. .......... ............ 4-5
ENGINE DiSASSEMBLy .................. .. .. .. ...... ...... .......... 4-6
CYLINDER HEAD, CYLINDER, CAMSHAFT AND PISTON .. .. . . .. . . 4-6
STARTER IDLE GEAR AND CRANKCASE COVER (LEFT) ... .. ...... .4-9
CLUTCH, PRIMARY DRIVE GEAR AND BALANCER GEAR ........ 4-10
OIL PUMP AND SHIFT LEVER .... ...... .......................... 4-12
A.C . MAGNETO AND CAM CHAIN .. .... .. ........ .. .. .... .. .. .... 4-13
CRANKCASE (RIGHT) ...................... ...... ........ .. .. .... 4-15
SHIFTER AND TRANSMiSSiON .... .... ........ .. ...... .... ........ 4-16
BALANCER AND CRANKSHAFT .. .............. .. ........ .. ...... 4-17
OIL STRAINER .... ............ .. .... ......... ... .. .. .......... .... 4-17
ROCKER ARM .. ........ .. .. .......... .... .. .. .... .... ...... .... .. 4-18
VALVE ........... . .. . .. ...... . . . ....... .. . .. ..... . .. .. .. .. .. ...... 4- 19

INSPECTION AND REPAIR ...... .. ............ .. .................. ..4-21
CYLINDER HEAD . . ...... . ........ . ..... . ........ .. ................ 4-21
VALVE AND VALVE GUIDE .. .. .... ........ .... .................... 4-22
VALVE SEAT .................... ... .. . ...... . .............. . .. .... 4-23
VALVE SPRING .... .. ................ .. .. .... ...... .. .............. 4-27
CAMSHAFT .. . ... . .... . .. . ...... ......... . . .. ...................... 4-28
ROCKER ARM AND ROCKER ARM SHAFT ........................ 4-28
CAM CHAIN AND CAM SPROCKET .. .. .......................... 4-29
CAM CHIN GUIDE ...... .. .. .... ................................. .4-30
CYLINDER AND PiSTON .......... .... ............................ 4-30
PISTON RING .................. .. ...... .... ...................... 4-32
PISTON PIN .... .. .... .. .. .. ...... .... ............................ 4-33
CLUTCH .. .......... . .... . ...... . .. .. ... . ..... . .. . ... . ............ 4-33
OIL PUMP ........... . .. .. .. . ... . ......... .. ....... .. .. . .......... 4-35
PRIMARY DRiVE .......................... .. ...... .. .............. 4-35
TRANSMISSION AND SHIFTER .... ........ .... .................... 4-36
SHIFT SHAFT STOPPER LEVER .............. .. .................... 4-37
STARTER DRIVE .... .. .. .......... .. .. .. .......................... 4-38
CRANKSHAFT ...... .. ........ .... ................................ 4-39
BALANCER DRIVE GEAR AN D BALANCER GEAR .. . .... . .... ...... 4-39
CRANKCASE ...................... .... ............................ 4-40
BEARING AND OIL SEAL .. .. ...... .. .. .. .. .... .................... 4-40
ENGINE ASSEMBLY AND ADJUSTMENT ........................ .. 4-41
VALVE ................ .. .. .. ................ . .. .. ................. 4-42
ROCKER ARM .. .... .. .. .. .... .. ........ .......................... 4-43
CRANKSHAFT AND BALANCER ...... .. ........ .... .............. 4-45
TRANSMISSION AND SHIFTER .. .... ...... .. .... .. ................ 4-48
OIL STRAINER .............. .... ...... .. .. .. .............. .. ..... .4-51
CRANKCASE ..... ... .. .......... . .... . .... ........ . .... . .......... 4-51
I----~
GEN
INFO
SPEC
R
1-----
INSP
ADJ
~-
1----....;;
ENG
CARB
SHIFT LEVER AND OIL PUMP .. ........ .. ...... .. ................ 4-52 CHAS
CAM CHAIN ......... . . ..... ...... ....... .... ........... . ..... . ... 4-54
:1.~~O~~g~~~~D~~ :. ~.~~I.~~~~ .. ~~~~. ~~ . ~ . ~~~~~~.F.~::::::::: ::~~~ Iii
BALANCER GEAR, PRIMARY DRIVE GEAR,
CLUTCH AND OIL FILTER ............ .... ........ .. .............. 4-70
STARTER IDLE GEAR AND CRANKCASE COVER (LEFT) .......... 4-74
REMOUNTING ENGINE .. .. .... .. ...... .... .. .. .. .................. 4-75
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TRBL
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CHAPTER 5.
CARBURETION
CARBURETOR .. . .... ... . ... .. . . ............ . .... . ........... . . .. ... 5-1
SECTIONAL VIEW ......... . .............. . .... .. ... . .. . . . ......... 5-2
REMOVAL ... ... ...... . ...... . ................ . ... . ....... . . ... . . 5-3
DISASSEMBLY ... . ..... . .......... .... .. ...... .. . .. ... . ....... .. . 5-4
INSPECTION . . .. ... . ............ . .. . .... .. ......... ... .. .... ... 5-7
ASSEMBLY ... . . . ............. . ............. .. . ... ... . . .. . ...... · 5-9
INSTALLATION ...... .......... . .. . .... . ......... , . . . ... .. . ... . .5- 14
FUEL LEVEL ADJUSTMENT. ... . ... . ......... . . .. ....... .. . . ...... ·5-15
CHAPTER 6.
CHASSIS
FRONT WHEEL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6-1
REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
STATIC WHEEL BALANC E ADJUSTMENT. . . . . . . . . . . . . . . . . . . .. 6-5
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
REAR WHEEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6-8
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6-9
INSPECTION ............... .. ........ .. ................. 6-10
INSTALLATION . . .... . ... .. . . ....... . ... ... ..... . .... ... . 6- 11
FRONT AND REAR BRAKE .. ... ............. . ........ . .... . . 6- 13
BRAKE PAD REPLACEMENT .... . .. ... ..... . .... . ... . .... . . . 6- 15
CALIPER DISASSEMBLY .......... .. . . ....... ... .. .... . . . . 6- 20
MASTER CYLINDER DISASSEMB LY ....... . ................. 6-23
INSPECTION AND REPAIR ........ . ..... . ........ . ... . ..... 6- 25
CALIPER ASSEMBL Y . .. . ........... . . . .. . ................ 6-29
MASTER CYLINDER ASSE MB LY ................. . ....... . .. 6- 34
FRONT FORK .. . . . .......... ... ....... .. .. . .... ... . . .. ... . . 6-39
REMOVAL ......................... . ... ... .......... . ... 6- 40
DISASSEMBL Y ... . ... . .. .. ..... .. ... . .. . ....... ... ... . .. 6- 41
INSPECTION . ..... .. ................................ . ... 6-43
ASSEMBLY .. . . . . .. ... . ...... .. ................ . ........ 6-44
INSTALLATION .. . ............ . ......... . ... . ... . ...... .. 6- 47
STEERING HEAD AND HAND LEBAR . ... . ...... ... ...... . ...... 6- 48
REMOVAL ........ . ... . ...................... . .... ... . . . 6- 49
INSPECTION ................... . . . ...... . .. . ...... . ..... 6-52
INST ALLATION . . .... . ........... . ... . ... . . ..... ... . ..... 6- 53

REAR SHOCK ABSORBER AND SWINGARM .................... 6-58
HANDLING NOTES ...................... ........ . ........ 6-60
NOTES ON DISPOSAL ........ . ......... ................. . 6-60
REMOVAL . ... .. .. ....... . .......... ..... .. ...... . ...... 6-61
INSPECTION ................ . ... . ...... . . .. ... . .. . ...... 6-64
SIDE CLEARANCE ADJUSTMENT ... ........ ........ ..... ... 6-65
INSTALLATION . .......... ...... ... .. ........ ... ... ...... 6-67
DRIVE CHAIN AND SPROCKET ............................... 6-71
REMOVAL ........................................ ...... 6-72
INSPECTION .......... .. . ..... ........ . .. .. . ....... . .... 6-73
INSTALLATION ............ .. ... .... ..................... 6-76
CHAPTER 7.
ELECTRICAL
XT600EA/EAC WIRING DIAGRAM ............ ......................... 7-1
COLOR CODE .... .............. ............... ......... .. . ......... 7-2
ELECTRICAL COMPONENTS ...... ..... . . ............................. 7-3
CHECKING OF SWITCHES .... " ...................................... 7-5
SWITCH CONNECTION AS SHOWN IN MANUAL .................. 7-5
CHECKING SWITCH FOR TERMINAL CONNECTION ................ 7-5
CHECKING OF BULBS (FOR HEADLIGHT, TAIL/BRAKE LIGHT,
FLASHER LIGHT, METER LIGHT, ETC.) .................................. 7-8
KINDS OF BULBS ......... . . .. .. ........ ..... .......... ............ 7-8
CHECKING BULB CONDITION ...................................... 7-8
IGNITION SYSTEM .......... ....................... ................. 7-11
CIRCUIT DIAGRAM ........ ............ ............................ 7-11
TROUBLESHOOTING .............................................. 7-13
ELECTRICAL STARTING SYSTEM .................................. 7-21
CIRCUIT DIAGRAM ................................. , .. " .......... 7-21
STARTING CIRCUIT OPERATION ............. ..................... 7-23
TROUBLESHOOTING .............................................. 7-24
STARTER MOTOR .. . ................................... ... ....... 7-30
CHARGING SYSTEM ..... ...... .. ................................... 7-35
CIRCUIT DIAGRAM ................................................ 7-35
TROUBLESHOOTING .................... . ............. . ........... 7-37
LIGHTING SYSTEM .................................................. 7-41
CIRCUIT DIAGRAM ................................................ 7-41
TROUBLESHOOTING .............................................. 7-43
LIGHTI NG SYSTEM CHECK ........................................ 7-46
~
t----~
GEN
INFO
SPEC
fi
INSP
ADJ
ENG
•
t-----
CARS
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t-----
CHAS
ELEC

SIGNAL SYSTEM......... .. ............ .. ..................................... .. ................7-51
CIRCUIT DIAGRAM .. .......... .. ....................... .. ........... .. ....................7-51
TROUBLESHOOTING ..... .. ...................... .. ... .. ............................ .. . .. . 7-53
SIGNAL SYSTEM CHECK ...................... .. ........ .. ............................. 7-55
CHAPTER 8.
TROUBLESHOOTING
STARTING FAILURE/HARD STARTING ............................................·8-1
FUEL SYSTEM ........·.... ·· .... ....·..............· .. .... ·· ......·........· .. ....·........· .. 8-1
ELECTRICAL SYSTEM .......... .. ...........................................·············· 8-2
COMPRESSION SYSTEM .... .. ............... .. ................................··· .. ······8-2
POOR IDLE SPEED
PERFORMANCE ............................ .. ............ .. ...... ·8-3
POOR IDLE SPEED PERFORMANCE .... .. .............. .. .... .. .... .. .............. 8-3
POOR MEDIUM AND HIGH SPEED PERFORMANCE ........................ 8-3
POOR MEDIUM AND HIGH SPEED PERFORMANCE .. .. .................... 8-3
FAULTY GEAR SHIFTING ·................ .. ·· .. .. ··· .. ·........·.... ·· ......·..........·.... ·8-4
HARD SHIFTING .........................................................··············· ·· ····8-4
CHANGE PEDAL DOES NOT MOVE .. ·........ .. ..........................·.......... ·8-4
JUMP-OUT GEAR ......... .. .. .. ... .. ...................................·············· .. ····8-4
CLUTCH SLIPPING/DRAGGING .... .. .... .. ·............ .. ....................·........ ·8-5
CLUTCH SLIPPING .......................................................····················8-5
CLUTCH DRAGGING ..... .... .. .. .............. .. ..........................········· .. ······8-5
FAULTY BRAKE ........· .. ·......· .... ·......·........·....·........·....· .. ·............ .. ......· :8-6
POOR BRAKING EFFECT ........ .. ..............·................· .. .. ....···....·........ 8-6
FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION .. ·8-6
OIL LEAKAGE·· ·· ··················· ·· ···· ·· ······· ·· ···· ········································8-6
MALFUNCTION .........................
.. . .. .. .. ................ .. .. ·········· ·· ·· ············ ·8-6
INSTABLE HANDLING ....·....·....· .. ·· .. .. ........·..........· .. ·.......................... 8-7
INSTABLE HANDLING ............................................. .. .......···············8-7
FAULTY SIGNAL AND LIGHTING SYSTEM .. .. .. ............ .. .......... .. ......·8-8
HEADLIGHT DARK ........... .. ........ .. ...... .. ... .. ... ...............·············· ·· ······8-8
BULB BURNT OUT ·· ....·...... ·· .. ·............ ·· .. · ·· ....·...... .. ........................· 8-8
FLASHER DOES NOT LIGHT .. .. ........ .. .... .. ............ .. ........ .. ................ 8-8
FLASHER KEEPS ON ··· .. ···· .. .. ··· .. ·......· .. .. · .. ·.......... .. ·....·..........· .. · .. · .. ·8-8
FLASHER WINKS SLOWER····............................................. .. ......... .. · 8-9
FLASHER WINKS QUICKER .................................................. .. ........ 8-9
HORN IS INOPERATIVE .. · .. .. .. · .. .. ..........·.... ·· .................... ·· .. ........ .. ·8-9

OVERHEATING ...................................................... ······························8-9
OVERHEATING ...................................................... ···························8-9
XT600EA/EAC CIRCUIT DIAGRAM
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GEN
INFO
SPEC
ENG
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CARS
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CHAS

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GINEFNOI~I
MOTORCYCLE IDENTIFICATION. . ~.
-----------------------------------------------
GENERAL INFORMATION
1-1
MOTORCYCLE IDENTIFICATION
VEHICLE IDENTIFICATION NUMBER
The vehicle identification number CD is
stamped into the right side of the steering
head.
XT600EA (Except for California)
JYA3UYEO * LA000101
XT600EAC (For California)
JYA3UYCO * LA005101
NOTE: __________________________ __
The vehicle identification number is used to
identify your motorcycle and may be used to
register your motorcycle with the licensing au-
thority in your state.
ENGINE SERIAL NUMBER
The engine serial number CD is stamped into
the elevated part of the right rear section of the
engine.
Starting serial number:
XT600EA (Except for California)
3UY-000101
XT600EAC (For California)
3UY-005101
NOTE: ______________________ __
-The first three digits of these numbers are for
model identifications; the remaining digits are
the
unit production number.
-Designs and specifications are subject to change
without notice.

I,
GNEFN
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IMPORTANT INFORMATION ~-e>
------------------------------------------------------
1- 2
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL AND
DISASSEMBLY
1. Remove all dirt, mud, dust, and foreign
material before removing and disassembling.
2. Use proper tools and cleaning equipment .
Refer
to "SPECIAL TOOL."
3. When disassembling the motorcycle, keep
mated parts together. This includes gears,
cylinders, pistons, and other mated parts
that
have been "mated" through normal wear.
Mated parts must be reused as an assembly
or replaced.
4. During the
motorcycle disassembly, clean all
parts and place
them in trays in the order of
disassembly. This will speed up assembly time
and help assure that
all parts are correctly rein-
stalled.
5. Keep away
from fire.

IMPORTANT INFORMATION I ~~"blil'l"l
300·000
300·003
300·002
1-3
ALL REPLACEMENT PARTS
1. Use only genuine Yamaha parts for all replace-
ments. Use oil
and/or grease recommended
by Yamaha
for assembly and adjustment.
Other brands may be similar in function and
appearance,
but inferior in quality.
GASKETS, OIL SEALS, AND O-RINGS
1. All gaskets, seals and O-rings should be
replaced when an engine is overhauled.
All
gasket surfaces, oil seal lips and O-rings must
be cleaned.
2. Properly oil all mating parts and bearings dur-
ing reassembly.
Apply grease to the oil seal
lips.
LOCK WASHERS/PLATES AND COTTER
PINS
1. All lock washers /plates CD and cotter pins
must be replaced when they are removed.
Lock tab(s) should be bent along the
bolt or
nut flat(s) after the bolt or nut has been
properly tightened.
BEARINGS AND OIL SEALS
1. Install the bearing(s) and oil seal(s) with their
manufacturer's marks
or numbers facing out-
ward . (In other words, the stamped letters
must be on the side exposed to view.) When
installing oil seal(s), apply a light coating of
light-weight lithium base grease to the seal
lip(s). Oil the bearings liberally when installing.
G) Oil seal
Do not use compressed air to spin the bear-
ings dry. This causes damage to the bearing
surfaces.
G) Bearing

2
2
p
1-4
SPECIAL TOOLS I~~~I"I
CIRCLIPS
1. All circlips should be inspected carefully be-
fore reassembly.
Always replace piston pin
clips after one use. Replace distorted circlips.
When installing a circlip G) , make sure that
the sharp-edged corner ~ is positioned op-
posite
to the thrust ® it receives. See the
sectional view.
@ Shaft
SPECIAL TOOLS
The proper special tools are necessary for com -
plete and accurate
tune-up and assembly. Using
the
correct special tool will help prevent damage
caused by the use of improper tools or improvised
techniques.
FOR TUNE UP
1. Inductive timing light
PI N. YM-33277-A- G)
PI
N. 90890-031 09-®
This tool is necessary for adjusting ignition timing.
2. Fuel levle
gauge
PI N. YM-01312-A
PI N. 90890-01312
This gauge is used to measure the fuel level in
the
float chamber.
3.
Inductive tachometer
PI N. YU - 08036-A- G)
PI N. 90890-03113- ®
This tool is needed for detecting engine rpm.

1-5
4. Compression gauge
PI N. YU-33223-Q)
P/ N.90890-03081-®
Adapter (M 12)
PI N. YU-33223-3-@
Extension
PI N. 90890-04082-@
These gauges are used to measure the engine
compression.
5. Valve adjusting
tool
PI N. YM-08035-Q)
P/ N.90890-01311-®
This tool is necessary for adjusting the valve
clearance.
FOR ENGINE SERVICE
1. Universal clutch holder
PI N. YM-91 042-Q)
PI N. 90890-04086-®
This tool is used to hold the clutch when remov-
ing or installing the clutch boss locknut.
2. Crankcase separator
PIN. YU-01135-A
PIN. 90890-01135
This tool is necessary to separate the crankcase.
3. Valve spring compressor
PIN. YM-04019
PIN. 90890-04019
This tool is needed to remove and install the valve
assemblies.

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1-6
SPECIAL TOOLS I~EF~IHI
4. Valve guide remover 7 mm (0. 28in)
PIN. YM-01225-A
PIN. 90890-01225
This tool is used to remove the valve guides.
5. Valve guide reamer 7 mm (0.
28in)
PI N. YM-01227
PI N. 90890-01227
This tool is used to rebore the new valve guide.
6. Valve guide installer 7 mm (0.28in)
PI N. YM-04017
PI N. 90890-0401 7
This tool
is needed to install the valve guides
properly.
7. Valve seat cutter set
PI N. YM-91043
This tool
is needed to resurface the valve seat.
8. Piston pin puller
PI N.
YU-01304
PI N. 90890-01304
This tool is used to remove the piston pin.

1-7
SPECIAL TOOLS I~~~IHI
9. Slide hammer set
PI N. YU-01083-A-Q)
Slide hammer bolt
PI N. 90890-01083- ®
Weight
PI N. 90890-01084-@
10. Crankshaft installer set
PI N. YU-90050-Q)
Crankshaft installer pot
P/ N. 90890-01274-®
Crankshaft installer bolt
PIN . 90890-01275- @
11. Adapter # 10 (M 14)
PI N. YM-90069
PI N. 90890-04059
This tool is used to install the crankshaft.
12. Crank pot spacer
PI N. YM-91044
P/ N.90890-04081-Q)
Spacer
P/ N. 90890-01016-®
This tool is used to install the crankshaft.
13. Rotor holder
PI N.
YS-01880
PI N. 90890-01701
This tool is used to hold the rotor when remov-
ing or installing the rotor securing nut.