Yamaha SR125 1997 User manual

EB000000
SR125
SERVICE MANUAL
1996 by Yamaha Motor Co., Ltd.
1st Edition, September 1996
All rights reserved. Any reprinting or
unauthorized use without the written
permission of Yamaha Motor Co., Ltd.
is expressly prohibited.

NOTE:
WARNING
CAUTION:
EB001000 NOTICE
This manual was produced by the Yamaha Motor Company primarily for use byYamaha 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 mo-
torcycle has a basic understanding of the mechanical ideas and the procedures of motorcycle repair.
Repairs attempted by anyone without this knowledge are likely to render the motorcycle unsafe and
unfit for use.
YamahaMotorCompany,Ltd.,iscontinuallystrivingtoimproveallitsmodels.Modificationsandsignif-
icant changes in specifications or procedures will be forwarded to all authorized Yamaha dealers and
will appear in future aditions of this manual where applicable.
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!
FailuretofollowWARNINGinstructionscouldresultin severe injuryor
deathtothemotorcycleoperator,abystanderorapersoninspectingor
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.

1
2
6
7
6
43
8
YP002000 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 on 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 accompa-
nied by corresponding illustrations.
EXPLODED DIAGRAMS
Tohelpidentifypartsandclarifyproceduresteps,thereareexplodeddiagramsatstartofeachremoval
and disassembly section.
1. An easy-to-see exploded diagram 4is provided for disassembly and assembly jobs.
2. Numbers 5are given in the order of 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. Ajobinstructionchart 7accompaniestheexplodeddiagram, providingtheorderofjobs, namesof
parts, notes in jobs, etc.
5. Forjobsrequiringmoreinformation,thestep-by-stepformatsupplements 8aregiveninadditionto
the exploded diagram and the job instruction chart.

21
1
3
5
7
9
2
4
8
6
23 24
2220
18 1917
15
1413
11 12
10
GEN
INFO SPEC
ENG
CARB
ELEC
CHAS
INSP
ADJ
TRBL
SHTG
16
EB003000
ILLUSTRATED SYMBOLS
Illustrated symbols 1to 9are designed as
thumb tabs to indicate the chapter’s number
and content.
1General information
2Specifications
3Periodic inspection and adjustment
4Engine
5Carburation
6Chassis
7Electrical
8Troubleshooting
Illustrated symbols 9to 16 are used to identify
the specifications appearing in the text.
9Possible to maintain with engine mounted
10 Filling fluid
11 Lubricant
12 Special tool
13 Tightening
14 Wear limit, clearance
15 Engine speed
16 Ω, V, A
Illustratedsymbols 17 to 22 in theexploded dia-
grams indicate the types of lubricants and lu-
brication points.
17 Apply engine oil
18 Apply gear oil
19 Apply molybodenum disulfide oil
20 Apply wheel bearing grease
21 Apply lightweight lithium-soap baes grease
22 Apply molybdenum disulfide grease
Illustratedsymbols 23 to 24 in theexploded dia-
gramsindicatethewheretoapplylockingagent
23 and when to install new parts 24 .
23 Apply locking agent (LOCTITE)
24 Use new one

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

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 PROCEDURES 1-2. . . . . . . . . . . . . . .
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .