Yamaha XV1600A1999 User manual

EB000000
XV1600A (L)
SERVICE MANUAL
1998 by Yamaha Motor Co., Ltd.
First Edition, December 1998
All rights reserved. Any reproduction or
unauthorized use without the written
permission of Yamaha Motor Co., Ltd.
is expressly prohibited.

NOTE:
CAUTION:
EAS00002 NOTICE
This manual was produced by the Yamaha Motor Company, Ltd. primarily for use by Yamaha dealers
andtheirqualifiedmechanics.Itisnotpossibletoincludealltheknowledgeofamechanicinonemanu-
al. Therefore, anyone who uses this book to perform maintenance and repairs on Yamaha vehicles
shouldhaveabasicunderstandingofmechanicsandthetechniquestorepairthesetypesofvehicles.
Repair and maintenance work attempted by anyone without this knowledge is likely to render the ve-
hicle unsafe and unfit for use.
Yamaha Motor Company,Ltd.iscontinuallystrivingtoimproveallofitsmodels.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.
Designs and specifications are subject to change without notice.
EAS00004
IMPORTANT MANUAL INFORMATION
Particularly important information is distinguished in this manual by the following.
The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED!
FailuretofollowWARNINGinstructionscouldresultinsevere injuryordeathto
themotorcycleoperator,abystanderorapersonchecking or repairing the mo-
torcycle.
ACAUTIONindicatesspecialprecautionsthatmustbetaken to avoid damage
to the motorcycle.
NOTE: A NOTE provides key information to make procedures easier or clearer.

12
4
7
3
8
5
6
EAS00007 HOW TO USE THIS MANUAL
This manual is intended as a handy, easy-to-read reference book for the mechanic. Comprehensive
explanations of all installation, removal, disassembly, assembly, repair and check procedures are laid
out with the individual steps in sequential order.
1The manual is divided into chapters. An abbreviation and symbol in the upper right corner of each page indi-
cate the current chapter.
Refer to “SYMBOLS”.
2Each chapter is divided into sections. The current section title is shown at the top of each page, except in
Chapter 3 (“PERIODIC CHECKS AND ADJUSTMENTS”), where the sub-section title(-s) appears.
3Sub-section titles appear in smaller print than the section title.
4To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each removal
and disassembly section.
5Numbersaregivenintheorderofthejobsintheexplodeddiagram.Acirclednumberindicatesadisassembly
step.
6Symbols indicate parts to be lubricated or replaced.
Refer to “SYMBOLS”.
7Ajob instruction chartaccompanies the explodeddiagram, providingthe order ofjobs, names ofparts, notes
in jobs, etc.
8Jobs requiring more information (such as special tools and technical data) are described sequentially.

21
1
3
5
7
9
2
4
8
6
23 24
2220
18 1917
1615
1413
11 12
10
GEN
INFO SPEC
ENG CARB
ELEC
CHK
ADJ
TRBL
SHTG
CHAS
********
SYMBOLS
The following symbols are not relevant to every
vehicle.
Symbols 1to 8indicate the subject of each
chapter.
1General information
2Specifications
3Periodic checks and adjustments
4Chassis
5Engine
6Carburetor
7Electrical system
8Troubleshooting
Symbols 9to 16 indicate the following.
9Serviceable with engine mounted
10 Filling fluid
11 Lubricant
12 Special tool
13 Tightening torque
14 Wear limit, clearance
15 Engine speed
16 Electrical data
Symbols 17 to 22 intheexplodeddiagramsindi-
cate the types of lubricants and lubrication
points.
17 Engine oil
18 Gear oil
19 Molybdenum disulfide oil
20 Wheel bearing grease
21 Lithium soap base grease
22 Molybdenum disulfide grease
Symbols 23 to 24 intheexplodeddiagramsindi-
cate the following.
23 Apply locking agent (LOCTITE)
24 Replace the part

GENERAL INFORMATION
SPECIFICATIONS
PERIODIC CHECKS AND
ADJUSTMENTS
ENGINE
CARBURETION
CHASSIS
ELECTRICAL SYSTEM
TROUBLESHOOTING
GEN
INFO 1
SPEC 2
3
ENG 5
CARB 6
CHAS 4
ELEC 7
TRBL
SHTG 8
CHK
ADJ
******** TABLE OF CONTENTS

E
GEN
INFO
CONTENTS
GENERAL INFORMATION
MOTORCYCLE IDENTIFICATION 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VEHICLE IDENTIFICATION NUMBER 1-1. . . . . . . . . . . . . . . . . . . . . . . . .
MODEL CODE 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FEATURES 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IMPORTANT INFORMATION 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PREPARATION FOR REMOVAL AND DISASSEMBLY 1-6. . . . . . . . . .
REPLACEMENT PARTS 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GASKETS, OIL SEALS AND O-RINGS 1-6. . . . . . . . . . . . . . . . . . . . . . . .
LOCK WASHERS/PLATES AND COTTER PINS 1-7. . . . . . . . . . . . . . . .
BEARINGS AND OIL SEALS 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CIRCLIPS 1-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CONNECTIONS 1-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 1-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

E
GEN
INFO

1-1
MOTORCYCLE IDENTIFICATION GEN
INFO
EAS00014
GENERAL INFORMATION
MOTORCYCLE IDENTIFICATION
EAS00017
VEHICLE IDENTIFICATION NUMBER
Thevehicleidentificationnumber 1isstamped
into the right side of the steering head pipe.
EAS00018
MODEL CODE
The model code label 1is affixed to the frame.
This information will be needed to order spare
parts.

1-2
FEATURES GEN
INFO
1
1
1
1
EAS00019
FEATURES
Twin spark plugs
For this model, two spark plugs are incorpo-
rated per each cylinder.
By using two spark plugs, the combustion time
in the combustion chamber is shortened in an
attempt to improve torque.
Speed sensor
The speed sensor is installed to the crankcase
anditdetectsthenumberofpassinggearswhile
the vehicle is running in 5th gear and sends the
informationoutasanelectricalsignaltotheigni-
tor unit.
Self-diagnosis device
Thismodelisequippedwithaself-diagnosisde-
vice that has four functions.
Theenginetroubleindicatorlightwillcomeonor
flash if trouble occurs in an engine monitoring
circuit.
Circuit Indicator lights Number
of
flashes
Throttle
position
sensor
Engine trouble
indicator light 3
Speed
sensor Engine trouble indicator light 4
Solenoid Engine trouble
indicator light 6
Fuel level
meter Fuel level indicator light 8
Refer to “SELF-DIAGNOSIS” in chapter 7.

1-3
FEATURES GEN
INFO
Auto decompression mechanism
The auto decompression mechanism occurs when the engine is started. When the engine is started
the decompression cam and pin raise the exhaust valve lifters, push the push rods, move the rocker
arms, and lower the exhaust valves which compress the cylinder. When the cylinder is compressed,
pressure is released immediately, resulting in smoother engine starting capabilities and smoother
crankshaft revolutions.
1Decompression solenoid
2Decompression solenoid rod
3Decompression connector
4Decompression lever
5Decompression push rod
6Decompression cam
7Pin
8Spring
9Camshaft

1-4
FEATURES GEN
INFO
Operation
1. Whenthestarterswitchispushed,electricity
is run to the decompression solenoid 1
causingittopush outthedecompressionso-
lenoid rod 2.
2. When the decompression solenoid rod is
pushed out, the decompression connector
3movesthedecompressionlevers 4inthe
direction indicated by the arrows, and then
the levers push the decompression rods 5
toward the camshaft side.
3. The decompression cam 6is pushed in the
directionindicated bythearrow,andthenthe
pin 7raises the projection of the decom-
pression cam.
4. When the camshaft is rotated by the selftim-
ing motor, the exhaust valve lifters 8are
lifted by the pin just before top dead center
(TDC)andtheexhaustvalvepushrod 9and
valverockerarmsareoperated.Thus,open-
ing the exhaust valve becomes easy.
5. When the engine starts and reaches a spe-
cific engine speed the decompression sole-
noid is turned off and the decompression
system stops operating.

1-5
FEATURES GEN
INFO
Oil-pressure-operated valve lifters
Sincetheoil-pressure-operated valve-lifting mechanism maintains a valve clearance ofzero,periodic
valve clearance adjustments are unnecessary.
The advantages of this system as compared to conventional techniques include the following: me-
chanical noise is reduced, the camshaft action on the valves remains unaffected by engine speed or
temperature, and the valve timing is kept stable.
1Plunger
2Oil reservoir
3Check valve spring
4Check valve
5Spring retainer
6High-pressure chamber
7Plunger spring
8Valve lifter body
9Oil supply inlet
10 Push rod cup
11 Plunger retaining clip
12 Valve push rod
The oil-pressure-operated valve-lifting system functions as follows:
1. As the camshaft rotates, the valve lifter is pushed up by the passing cam lobe.
2. Since the check valve 4prevents the engine oil contained inside the high-pressure chamber from
escaping,theplunger 1movesup along withthevalvelifterbody 8andpushes upthepushrods,
causing the valve to be lifted.
3. Asthecamshaftcontinuestorotate,thevalveliftermovesbackdowntoitsoriginalposition,whereit
remains while the cam heel passes.
When a positive valve clearance is caused by either heat expansion of the cylinder head or engine oil
leaking from the valve lifter during stage 2, the plunger, which no longer receives pressure from the
push rod, is pushed up by the plunger spring 7.As a result, the valveclearance is zeroedand engine
oil is allowed to return to the high-pressure chamber from the reservoir 2throughthecheckvalve 4.
When, on the contrary, a negative valve clearance occurs (this is the case when the cam heel is pass-
ing the valve lifter, but the rocker arm, pushed by the push rods, is lifting the valve), the plunger 1
continues to receive pressure from the valve push rod. As engine oil contained inside the high-pres-
sure chamber leaks from the gaps between the valve lifter body 8and the plunger 1as well as be-
tweenthevalvelifterbody 8andthecheckvalve 4,theplunger 1moves down and the valve clear-
ance is zeroed.

1-6
IMPORTANT INFORMATION GEN
INFO
EAS00020
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL AND DIS-
ASSEMBLY
1. Before removal and disassembly, remove all
dirt, mud, dust, and foreign material.
2. Use only the proper tools and cleaning
equipment.
Refer to “SPECIAL TOOLS”.
3. When disassembling, always keep mated
parts together. This includes gears, cylin-
ders,pistons,andother partsthathavebeen
“mated” through normal wear. Mated parts
mustalwaysbereusedorreplaced as an as-
sembly.
4. During disassembly, clean all of the parts
and place them in trays in the order of disas-
sembly. This will speed up assembly and al-
low for the correct installation of all parts.
5. Keep all parts away from any source of fire.
EAS00021
REPLACEMENT PARTS
Use only genuine Yamaha parts for all replace-
ments. Use oil and grease recommended by
Yamaha for all lubrication jobs.
Other brands may be similar in function and ap-
pearance, but inferior in quality.
EAS00022
GASKETS, OIL SEALS AND O-RINGS
1. When overhauling the engine, replace all
gaskets, seals, and O-rings. All gasket sur-
faces, oil seal lips, and O-rings must be
cleaned.
2. During reassembly, properly oil all mating
parts and bearings and lubricate the oil seal
lips with grease.

1-7
IMPORTANT INFORMATION GEN
INFO
CAUTION:
EAS00023
LOCK WASHERS/PLATES AND COTTER
PINS
After removal, replace all lock washers/plates
1andcotterpins. Aftertheboltornut hasbeen
tightenedtospecification,bendthelockwasher
tabs and the cotter pin ends along a flat of the
bolt or nut.
EAS00024
BEARINGS AND OIL SEALS
1. Install bearings and oil seals so that the
manufacturer’s marks or numbers are vis-
ible.Wheninstallingoilseals,lubricatetheoil
seallipswithalightcoatoflithiumsoapbase
grease.Oilbearingsliberallywheninstalling,
if appropriate.
1Oil seal
Donotspin the bearing withcompressedair
because this will damage the bearing sur-
faces.
1Bearing
EAS00025
CIRCLIPS
Before reassembly, check all circlips carefully
and replace damaged or distorted circlips. Al-
ways replace piston pin clips after one use.
When installing a circlip 1, make sure the
sharp-edged corner 2is positioned opposite
the thrust 3that the circlip receives.
4Shaft

1-8
CHECKING THE CONNECTIONS GEN
INFO
NOTE:
NOTE:
NOTE:
EAS00026
CHECKING THE CONNECTIONS
Check the leads, couplers, and connectors for
stains, rust, moisture, etc.
1. Disconnect:
lead
coupler
connector
2. Check:
lead
coupler
connector
Moisture Dry with an air blower.
Rust/stains Connect and disconnect sev-
eral times.
3. Check:
all connections
Loose connection Connect properly.
If the pin 1on the terminal is flattened, bend it
up.
4. Connect:
lead
coupler
connector
Make sure all connections are tight.
5. Check:
continuity
(with the pocket tester)
Pocket tester
90890-03112
If there is no continuity, clean the terminals.
When checking the wire harness, perform
steps (1) to (3).
As a quick remedy, use a contact revitalizer
available at most part stores.

1-9
SPECIAL TOOLS GEN
INFO
EAS00027
SPECIAL TOOLS
The following special tools are necessary for complete and accurate tune-up and assembly. Use only
theappropriatespecialtoolsasthiswillhelpprevent damage caused by the use of inappropriate tools
or improvised techniques. Special tools, part numbers, or both may differ depending on the country.
When placing an order, refer to the list provided below to avoid any mistakes.
Tool No. Tool name/Function Illustration
90890-01080
Flywheel puller
Thistoolisusedtoremovethegeneratorrotor.
T-handle
90890-01326
Damper rod
holder
90890-01294
T-handle
Damper rod holder
These tools are used to hold the cartridge
cylinder when loosening or tightening the
cartridge cylinder bolt.
90890-01312
Fuel level gauge
This tool is used to measure the fuel level in
the float chamber.
90890-03141
Timing light
This tool is used to check the ignition
timing.
90890-03170
Belt tention gauge
This tool is used to measure the drive belt
slack.
Fork seal
driver weight
90890-01367
Adapter
90890-01374
Fork seal driver weight
Adapter
These tools are used to install the front
fork’s oil seal and dust seal.
90890-06754
Ignition checker
This tool is used to check the ignition
system components.
90890-04019
Valve spring compressor
This tool is used to remove or install the
valve assemblies.

1-10
SPECIAL TOOLS GEN
INFO
Tool No. Tool name/Function Illustration
90890-04064
Valve guide remover (6 mm)
This tool is used to remove or install the
Valve guides.
90890-04065
Valve guide installer
This tool is used to install the valve guides.
90890-04066
Valve guide reamer
This tool is used to rebore the new valve
guides.
90890-04086
Clutch holding tool
This tool is used to hold the clutch boss
when removing or installing the clutch
boss nut.
90890-01701
Sheave holder
This tool is used to hold the generator
rotor when removing or installing the
90890
-
01701
rotor
when
removing
or
installing
the
generator rotor bolt, generator shaft bolt or
pickup coil rotor bolt.
90890-01304
Piston pin puller set
This tool is used to remove the piston
pins.
90890-03009
Micrometer (75 100 mm)
This tool is used to measure the piston
skirt diameter.
90890-03017
Cylinder bore gauge (50 100 mm)
Thistool is used to measure the cylinder bore.
90890-03112
Pocket tester
This tool is used to check the electrical
system.