Yamaha TDM850 1996 User manual

EB000000
TDM850 ’96
SERVICE MANUAL
1996 by Yamaha Motor Co., Ltd.
First edition, March 1996
All rights reserved. Any reproduction or
unauthorized use without the written
permission of Yamaha Motor Co., Ltd.
is expressly prohibited.

WARNING
CAUTION:
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 as-
sumed that persons using this book to perform maintenance and repairs on Yamaha motorcycles have a
basicunderstandingofthemechanicalconceptsandproceduresinherentinmotorcyclerepairtechnology.
Withoutsuchknowledge,attemptedrepairsorservicetothismodelmayrenderifunfittouseand/orunsafe.
YamahaMotorCompany,Ltd.iscontinuallystrivingtoimproveallmodelsmanufacturedbyYamaha.Modifi-
cationsand significant changes in specificationsor procedures will be forwardedto all Authorized Yamaha
dealers and will, where applicable, appear in future editions of this manual.
PARTICULARY IMPORTANT INFORMATION
This material is distinguished by the following notation.
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 motorcycle operator, a bystander, or a person inspecting or
repairing the motorcycle.
A CAUTION indicates special precautions that must be taken to avoid
damage to the motorcycle.
NOTE: A NOTE provides key information to make procedures easier or clearer.

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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.
2ndtitle 2 :Thistitleindicatesthesectionofthechapterandonlyappearsonthefirstpageofeachsection.
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
Tohelp identify parts and clarify procedure steps, there are exploded diagramsatthestartofeachremoval
and disassembly section.
1. An easy-to-see exploded diagram 4 is provided for removal and disassembly jobs.
2. Numbers 5 are given in the order of the jobs in the exploded diagram. A number that is enclosed by a
circle indicates a disassembly step.
3. Anexplanationofjobsandnotesispresentedinaneasy-to-readwaybytheuseofsymbolmarks 6 .The
meanings of the symbol marks are given on the next page.
4. A job instruction chart 7 accompanies the exploded diagram, providing the order of jobs, names of
parts, notes in jobs, etc.
5. Forjobs requiringmoreinformation,thestep-by-step formatsupplements 8 aregiveninaddition tothe
exploded diagram and the job instruction chart.

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3
5
7
9
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4
8
6
24 25
2321
19 2018
16 1715
1413
11 12
10
GEN
INFO SPEC
ENG
CARB
ELECCHAS
COOL
INSP
ADJ
TRBL
SHTG
EB003000
ILLUSTRATED SYMBOLS
Illustrated symbols 1 to 9 are printed on top
rightofeachpageandindicatethesubjectofeach
chapter.
1General information
2Specifications
3Periodic inspections and adjustments
4Engine
5Cooling system
6Carburetion
7Chassis
8Electrical
9Troubleshooting
Illustrated symbols 10 to 17 are used to identify
the specifications appearing in the text.
10 Can be serviced with engine mounted
11 Filling fluid
12 Lubricant
13 Special tool
14 Torque
15 Wear limit, clearance
16 Engine speed
17 Ω, V, A
Illustrated symbols 18 to 23 in the exploded dia-
gramsindicatethetypes of lubricants and lubrica-
tion points.
18 Apply engine oil
19 Apply gear oil
20 Apply molybdenum disulfide oil
21 Apply wheel bearing grease
22 Apply lightweight lithium soap base grease
23 Apply molybdenum disulfide grease
Illustrated symbols 24 to 25 in the exploded dia-
grams indicate where to apply a locking agent 24
and when to install new parts 25 .
24 Apply locking agent (LOCTITE)
25 Replace

GENERAL INFORMATION
SPECIFICATIONS
PERIODIC INSPECTION AND
ADJUSTMENT
ENGINE OVERHAUL
COOLING SYSTEM
CARBURETION
CHASSIS
ELECTRICAL
TROUBLESHOOTING
GEN
INFO 1
SPEC 2
3
ENG 4
COOL 5
CARB 6
CHAS 7
ELEC 8
TRBL
SHTG 9
INSP
ADJ
INDEX

GEN
INFO
1

GEN
INFO
CHAPTER 1.
GENERAL INFORMATION
MOTORCYCLE IDENTIFICATION 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FRAME SERIAL NUMBER 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ENGINE SERIAL NUMBER 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MODEL LABEL 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IMPORTANT INFORMATION 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PREPARATION FOR REMOVAL 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ALL REPLACEMENT PARTS 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GASKETS, OIL SEALS, AND O-RINGS 1-2. . . . . . . . . . . . . . . . . . . . . . . . . .
LOCK WASHERS/PLATES AND COTTER PINS 1-3. . . . . . . . . . . . . . . . . .
BEARINGS AND OIL SEALS 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CIRCLIPS 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING OF CONNECTIONS 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HOW TO USE THE CONVERSION TABLE 1-5. . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

GEN
INFO

1-1
MOTORCYCLE IDENTIFICATION GEN
INFO
NOTE:
NOTE:
EB100000
GENERAL INFORMATION
MOTORCYCLE IDENTIFICATION
VEHICLE IDENTIFICATION NUMBER
The vehicle identification number 1 is stamped
into the right side of the steering head.
Thevehicleidentificationnumberisusedtoidenti-
fy the motorcycle and may be used to register the
motorcycle with a licensing authority.
EB100030
ENGINE SERIAL NUMBER
The engine serial number 1 is stamped into the
crankcase.
The first three digits of the engine serial number
indicate the model type; the remaining digits are
the unit production number.
MODEL LABEL
Themodellabel 1 isaffixedto theframe.Thisin-
formation will be needed to order spare parts.

1-2
IMPORTANT INFORMATION GEN
INFO
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL
1. Removeall dirt,muddust,and foreignmaterial
before removal and disassembly.
2. Use proper tools and cleaning equipment.
Refer to “SPECIAL TOOLS”.
3. When disassembling the motorcycle keep
mated parts together. This includes gears, cyl-
inders, pistons, and other mated parts that
have been “mated” through normal wear.
Matedpartsmustbereusedasanassemblyor
replaced.
4. During the motorcycle disassembly, clean all
partsandplacethemintraysintheorderofdis-
assembly. This will speed up assembly time
andhelpassurethatallpartsarecorrectlyrein-
stalled.
5. Keep away from fire.
ALL REPLACEMENT PARTS
1. UseonlygenuineYamahapartsforallreplace-
ments. Use oil and/or grease recommended
byYamahaforassembly and adjustment. Oth-
er brands may be similar in function and ap-
pearance, but inferior in quality.
GASKETS, OIL SEALS, AND O-RINGS
1. All gaskets, seals and O-rings should be re-
placed when an engine is overhauled.
All gaskets surfaces, oil seal lips and O-rings
must be cleaned.
2. Properlyoilallmatingparts and bearing during
reassembly. Apply grease to the oil seal lips.

1-3
IMPORTANT INFORMATION GEN
INFO
CAUTION:
LOCK WASHERS/PLATES AND COTTER PINS
1. All lock washers/plates 1 and cotter pins
must be replaced when they are removed.
Locktab(s)should bebentalongtheboltornut
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 word, the stamped letters must
be on the side exposed to view.) When instal-
ling oil seal(s), apply a light coating of light-
weightlithiumbasegreasetotheseallip(s).Oil
the bearings liberally when installing.
1Oil seal
Do not use compressed air to spin the bear-
ings dry. This causes damage to the bearing
surfaces.
2Bearing
CIRCLIPS
1. Allcirclipsshouldbeinspectedcarefullybefore
reassembly.Always replace piston pinclipsaf-
ter one use. Replace distorted circlips. When
installingacirclips 1 ,makesurethatthesharp
edged corner 2 is positioned opposite to the
thrust 3 it receives. See the sectional view.
4Shaft

1-4
CHECKING OF CONNECTIONS GEN
INFO
NOTE:
NOTE:
CHECKING OF CONNECTIONS
Dealingwithstains,rust,moisture,etc.onthecon-
nector.
1. Disconnect:
Connector
2. Dry each terminal with an air blower.
3. Connect and disconnect the connector two or
three times.
4. Pull the lead to check that it will not come off.
5. If the terminal comes off, bend up the pin 1
and reinsert the terminal into the connector.
6. Connect:
Connector
The two connectors “click” together.
7. Check for continuity with a tester.
If there is no continuity, clean the terminals.
Be sure to perform the steps 1 to 7 listed above
when checking the wireharness.
Forafieldremedy,useacontactrevitalizeravail-
able on the market.
Use the tester on the connector as shown.

1-5
HOW TO USE THE CONVERSION TABLE GEN
INFO
HOW TO USE THE CONVERSION
TABLE
Allspecificationdatain this manual are listedinSI
and METRIC UNITS.
Use this table to convert METRIC unit data to IM-
PERIAL unit data.
Ex.
METRIC MULTIPLIER IMPERIAL
**mm 0.03937 = **in
2 mm 0.03937 = 0.08 in
CONVERSION TABLE
METRIC TO IMPERIAL
Metric unit Multiplier Imperial unit
Torque
mSkg
mSkg
cmSkg
cmSkg
7.233
86.794
0.0723
0.8679
ftSlb
inSlb
ftSlb
inSlb
Weight
kg 2.205 lb
Weight
g
g 0.03527 oz
Speed km/hr 0.6214 mph
Dis-
tance
km
m
m
cm
mm
0.6214
3.281
1.094
0.3937
0.03937
mi
ft
yd
in
in
Volume/
Capacity
cc (cm3)
cc (cm3)
lit (liter)
lit (liter)
0.03527
0.06102
0.8799
0.2199
oz (IMP liq.)
cuSin
qt (IMP liq.)
gal(IMPliq.)
Miscel-
laneous
kg/mm
kg/cm2
Centigrade
(_C)
55.997
14.2234
9/5+32
lb/in
psi (lb/in2)
Fahrenheit
(_F)

1-6
SPECIAL TOOLS GEN
INFO
SPECIAL TOOLS
The proper special tools are necessary for complete 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. The shape and part number used for the special tool differ by country, so two types are pro-
vided. Refer to the list provided to avoid errors when placing an order.
Tool No. Tool name/How to use Illustration
90890-01083
90890-01084 Slide hammer bolt Weight
These tools are used to remove the
main axle assembly cover.
90890-01304 Piston pin puller
This tool is used to remove the piston
pin.
90890-01312 Fuel level gauge
This gauge is used to measure the fuel
level in the float chamber.
90890-01325
90890-01352 Radiator cap tester Adapter
This tester is needed for checking the
cooling system.
90890-01362
90890-01382 Flywheel puller Crankshaft protector
These tools are used to remove the A.C.
magneto.
90890-01367
90890-01374 Fork seal driver weight Adapter
These tools are used when installing the
fork seal.
90890-01326
90890-01465 T-handle Damper rod holder
These tools are used to loosen and
tighten the front fork damper rod
holding bolt.
90890-01403 Ring nut wrench
This tool is used to loosen and tighten
the steering ring nut.

1-7
SPECIAL TOOLS GEN
INFO
Tool No. Tool name/How to use Illustration
90890-01701 Sheave holder
This tool is used to hold the rotor when
loosening and tightening the rotor bolt.
90890-03081 Compression gauge
This gauge is used to measure the
engine compression.
90890-03094 Vacuum gauge
This gauge is needed for carburetor
synchronization.
90890-03112 Pocket tester
This instrument is invaluable for
checking the electrical system.
90890-03113 Engine tachometer
This tool is needed for detecting
engine rpm.
90890-03141 Timing light
This tool is necessary for checking
ignition timing.
90890-04016 Valve guide remover, installer and
reamer (5.5 mm)
These tools are used to remove, install
and rebore the valve guide.
90890-04019
90890-04108 Valve spring compressor Attachment
These tools are needed to remove and
install the valve assemblies.
90890-04086 Universal clutch holder
This tool is used to hold the clutch when
removing or installing the clutch boss
nut.
90890-06754 Ignition checker
This instrument is necessary for
checking the ignition system components.

1-8
SPECIAL TOOLS GEN
INFO
Tool No. Tool name/How to use Illustration
90890-85505 Yamaha bond No. 1215
This sealant (bond) is used on crankcase
mating surfaces, etc.

SPEC
2