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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·C.rbond'POltll
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NOTE : ---'- -----''-----_
Ro .. ~. Il1e h •• d ."ver.' lime. 10 ."Dld re -
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____ ____ FR _ ON _ TF_OR_K ICHAS I~0 1
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(J)
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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
ELEC
?
~---.
TRBL
SHTG

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