2003 YAMAHA TTR125 diagram

EC083000
MANUAL FORMAT
All of the procedures in this manual are organized in a sequential, step-by-step format. The informa-
tion has been complied to provide the mechanic with an easy to read, handy reference that contains
comprehensive explanations of all disassembly, repair, assembly, and inspection operations.
In this revised format, the condition of a faulty component will precede an arrow symbol and the
course of action required will follow the symbol, e.g.

Bearings
Pitting/damage
→
Replace.
EC084002
HOW TO READ DESCRIPTIONS
To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each
removal and disassembly section.
1. An easy-to-see exploded diagram
1
is provided for removal and disassembly jobs.
2. Numbers
2
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. An explanation of jobs and notes is presented in an easy-to-read way by the use of symbol
marks
3
. The meanings of the symbol marks are given on the next page.
4. A job instruction chart
4
accompanies the exploded diagram, providing the order of jobs,
names of parts, notes in jobs, etc.
5. Extent of removal
5
is provided in the job instruction chart to save the trouble of an unneces-
sary removal job.
6. For jobs requiring more information, the step-by-step format supplements
6
are given in addi-
tion to the exploded diagram and job instruction chart.

AUFBAU
Diese Anleitung wurde zusammengestellt, um
dem Benutzer ein leicht verständliches Nach-
schlagewerk in die Hand zu geben, in dem alle
dargestellten Arbeitsvorgänge (Ein- und Aus-
bau, Zerlegung und Zusammenbau, Prüfung
und Reparatur) detailliert und in der entspre-
chenden Reihenfolge beschrieben sind.
Je nach Zustand eines fehlerhaften Bauteils
weist ein Pfeilsymbol auf die erforderliche
Maßnahme hin. Beispiel:

Lager
Pitting/Beschädigung
→
Erneuern.
LESEN DER BESCHREIBUNGEN
Um bei der Identifikation der Teile zu helfen
und die Arbeitsschritte zu verdeutlichen, sind
Explosionsdiagramme am Beginn jedes Aus-
bau- und Demontageabschnittes dargestellt.
1. Für die Ausbau- und Demontagearbeiten
ist meistens ein übersichtliches Explosi-
onsdiagramm
1
dargestellt.
2. Die Nummern
2
in dem Explosionsdia-
gramm sind in der Reihenfolge der Arbeiten
aufgeführt. Eine in einen Kreis eingeschrie-
bene Nummer bezeichnet einen Demonta-
geschritt.
3. Eine Erläuterung der Arbeiten und Hinweise
ist durch ablesefreundliche Symbolmarkie-
rungen
3
gegeben. Die Bedeutungen der
Symbolmarkierungen sind auf der nächsten
Seite aufgeführt.
4. Eine Arbeitsanweisungstabelle
4
beglei-
tet das Explosionsdiagramm und gibt die
Arbeitsreihenfolge, Bezeichnung der Teile,
Hinweise zu den Arbeiten usw. an.
5. Der Umfang des Ausbaus
5
ist in der
Arbeitsanweisungstabelle aufgeführt, um
nicht erforderliche Ausbauarbeiten zu ver-
meiden.
6. Für Arbeiten, für die weitere Informatio-
nen benötigt werden, sind schrittweise
Ergänzungen
6
zusätzlich zu dem Explo-
sionsdiagramm und der Arbeitsanwei-
sungstabelle aufgeführt.
FORMAT DU MANUEL
Dans ce manuel, tous les procédés sont décrits pas à
pas. Les informations ont été condensées de sorte à
fournir à l’utilisateur un guide pratique et facile à
lire, contenant des explications claires pour tous les
travaux de démontage, réparation, remontage et
vérification.
L’état d’un organe défectueux est suivi d’une flè-
che indiquant les mesures à prendre. Exemple:
Roulements
Piqûres/endommagement → Remplacer.
COMMENT LIRE LES DESCRIP-
TIONS
Chaque section détaillant les étapes de démontage
ou de remontage est précédée de vues en éclaté qui
permettent de clarifier ces opérations.
1. Exemple de vue en éclaté 1 clarifiant les opé-
rations de démontage et de remontage.
2. Sur les vues en éclaté, les pièces sont numéro-
tées 2 dans l’ordre des opérations à effectuer.
Un chiffre entouré d’un cercle correspond à une
étape de démontage.
3. Les vues en éclaté portent également des sym-
boles 3 qui rappellent des points importants à
ne pas oublier. La signification de ces symboles
est expliquée à la page suivante.
4. Les vues en éclaté sont suivies d’un tableau 4
fournissant l’ordre des opérations, le nom des
pièces, des remarques, etc.
5. Pour éviter la dépose superflue de pièces, les
travaux de dépose 5 qu’il faut effectuer sont
repris dans le tableau de description du travail.
6. Pour les travaux nécessitant de plus amples
explications, la vue en éclaté et le tableau sont
suivis d’une description détaillée 6 des opéra-
tions.

ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols
1
to
6
are designed as
thumb tabs to indicate the chapter’s number
and content.
1
General information
2
Specifications
3
Regular inspection and adjustments
4
Engine
5
Chassis
6
Electrical
Illustrated symbols
7
to
D
are used to identify
the specifications appearing in the text.
7
With engine mounted
8
Special tool
9
Filling fluid
0
Lubricant
ATightening
BSpecified value, Service limit
CEngine speed
DResistance (Ω), Voltage (V), Electric current (A)
Illustrated symbols E to H in the exploded
diagrams indicate grade of lubricant and loca-
tion of lubrication point.
EApply engine oil
FApply molybdenum disulfide oil
GApply lightweight lithium-soap base grease
HApply molybdenum disulfide grease
Illustrated symbols I to J in the exploded
diagrams indicate where to apply a locking
agent and when to install new parts.
IApply locking agent (LOCTITE®)
JUse new one 12
34
56
78
90
AB
CD
EF
GH
IJ
GEN
INFOSPEC
INSP
ADJENG
CHAS–+ELEC
T R..
EM
LSM
LTNew

EC0A0000
CONTENTS
CHAPTER 1
GENERAL INFORMATION
DESCRIPTION
...........................................1-1
MACHINE IDENTIFICATION
.....................1-2
IMPORTANT INFORMATION
....................1-3
CHECKING OF CONNECTION
.................1-5
SPECIAL TOOLS
......................................1-6
CONTROL FUNCTIONS
............................1-9
FUEL
........................................................1-12
STARTING AND BREAK-IN
....................1-13
TORQUE-CHECK POINTS
......................1-16
TT-R125E
............................................1-16
TT-R125LWE
.......................................1-17
CLEANING AND STORAGE
...................1-18
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS
....................2-1
TT-R125E
..............................................2-1
TT-R125LWE
.........................................2-4
MAINTENANCE SPECIFICATIONS
..........2-7
ENGINE
....................................................2-7
CHASSIS
................................................2-15
TT-R125E
............................................2-15
TT-R125LWE
.......................................2-19
ELECTRICAL
.........................................2-23
GENERAL TORQUE
SPECIFICATIONS
...................................2-25
DEFINITION OF UNITS
...........................2-25
CABLE ROUTING DIAGRAM
.................2-26
CHAPTER 3
REGULAR INSPECTION AND
ADJUSTMENTS
MAINTENANCE INTERVALS
...................3-1
PRE-OPERATION INSPECTION
AND MAINTENANCE
................................3-3
ENGINE
......................................................3-4
CHASSIS
.................................................3-15
ELECTRICAL
...........................................3-32

CHAPTER 4
ENGINE
SEAT, FUEL TANK
AND SIDE COVERS
..................................4-1
MUFFLER
..................................................4-2
CARBURETOR
..........................................4-3
CYLINDER HEAD
....................................4-12
CAMSHAFT AND ROCKER ARMS
........4-20
VALVES AND VALVE SPRINGS
............4-24
CYLINDER AND PISTON
........................4-32
CLUTCH AND PRIMARY
DRIVEN GEAR
........................................4-40
OIL PUMP
................................................4-49
KICK AXLE AND SHIFT SHAFT
.............4-53
CDI MAGNETO
AND STARTER CLUTCH
.........................4-58
ENGINE REMOVAL
.................................4-63
CRANKCASE, CRANKSHAFT
AND BALANCER
....................................4-67
TRANSMISSION, SHIFT CAM
AND SHIFT FORK
...................................4-75
CHAPTER 5
CHASSIS
FRONT WHEEL AND FRONT BRAKE
(TT-R125E)
................................................5-1
FRONT WHEEL (TT-R125LWE)
...............5-8
FRONT BRAKE (TT-R125LWE)
..............5-12
REAR WHEEL AND REAR BRAKE
.......5-24
FRONT FORK
..........................................5-32
HANDLEBAR
...........................................5-41
STEERING
...............................................5-48
SWINGARM
.............................................5-54
REAR SHOCK ABSORBER
ASSEMBLY
.............................................5-61
CHAPTER 6
ELECTRICAL
ELECTRICAL COMPONENTS
AND WIRING DIAGRAM
...........................6-1
IGNITION SYSTEM
....................................6-2
ELECTRIC STARTING SYSTEM
...............6-6
CHARGING SYSTEM
...............................6-16

2 - 26
SPEC

CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Ground lead
2
Primary coil lead
3
Clamp
4
Wire harness
5
Starter relay lead
6
Rectifier/regulator lead
7
CDI magneto lead
8
Air vent hose
9
Neutral switch lead
0
Rear shock absorber assembly
sub-tank hose (TT-R125LWE
only)
A
Starting circuit cut-off relay lead
B
CDI unit lead
C
Corrugated tube
D
Brake hose holder (Brake cable
holder for the TT-R125E)
E
Brake hose (Brake cable for the
TT-R125E)
F
Cable guide
G
Main switch lead
H
Engine stop switch lead
I
Clutch switch lead
J
Start switch lead
K
CDI unit band
L
CDI unit
M
Connector cover
N
Rubber cover
O
Starter cable
P
Throttle cable
Q
Rectifier/regulator
Å
Fasten the primary coil lead and
ground lead.
ı
Fasten the wire harness at its
tape.
Ç
Fasten the wire harness and
CDI magneto lead in front of the
rear shock absorber assembly
bracket at the protecting tube
for the CDI magneto lead.
30~35 mm
(1.18~1.38 in)
E
DD
A
C
B-B
D-D
E
B
BC
TT-R125EA
L
1
3
4 2
3
35
3
36
7
3
3
8
9 0 A 3 B C
DEFGHIJKOP
7
4
0
3 3M
N
3Q
3 F
E
DË
◊
„
Ù
AB
AA
Û
ÁAC
N
Ì
Ï ‰ Î
Ç ı Å
Ó
È
Ô

Ò ˜ ˆ Ø ∏
ŒÂÍ ÊÂ

2 - 27
SPEC

CABLE ROUTING DIAGRAM
Î
After fastening the starter relay
lead, pass it on the left of the
chassis.
‰
Fasten the CDI magneto lead
and starter relay lead.
Ï
Fasten the wire harness.
Ì
Pass the rectifier/regulator lead
between the frame and air filter
case.
Ó
Do not allow the CDI magneto
lead to slacken except between
the two plastic locking ties.
È
Fasten the CDI magneto lead
over the engine bracket (rear).
Ô
Fasten the CDI magneto lead.

Pass the air vent hoses between
the engine and swingarm.
Ò
Fit the neutral switch lead into
the groove in the crankcase
cover.
˜
Pass the starting circuit cut-off
relay lead under the frame and
at the right of the chassis.
ˆ
Fasten the rear shock absorber
assembly sub-tank.
(TT-R125LWE only)
Ø
Pass the CDI unit lead on the
outside of the main switch lead,
engine stop switch lead, clutch
switch lead and start switch
lead.
∏After fastening the start switch
lead, clutch switch lead, engine
stop switch lead and main
switch lead, push their corru-
gated tube against the CDI unit
coupler.
ŒFasten the brake hose between
the paint marks.
ÂPass the brake hose (brake
cable for the TT-R125E)
through the cable guide.
ÍFit the CDI unit band over the
CDI unit bracket till it stops.
ÊFasten the brake cable.
30~35 mm
(1.18~1.38 in)
E
DD
A
C
B-B
D-D
E
B
BC
TT-R125EA
L
1
3
4 2
3
35
3
36
7
3
3
8
9 0 A 3 B C
DEFGHIJKOP
7
4
0
3 3M
N
3Q
3 F
E
DË
◊
„
Ù
AB
AA
Û
ÁAC
N
Ì
Ï ‰ Î
Ç ı Å
Ó
È
Ô

Ò ˜ ˆ Ø ∏
ŒÂÍ ÊÂ

2 - 28
SPECCABLE ROUTING DIAGRAM
ËAfter connecting the main
switch coupler, engine stop
switch coupler, clutch switch
coupler and start switch cou-
pler, put a connector cover on
the couplers and push them in
at the rubber cover end.
◊Pass the wire harness on the
outside of the main switch cou-
pler.
„Do not allow the primary coil
lead to slacken where it is bare
of the protecting tube.ÙFasten the CDI unit lead and
starting circuit cut-off relay lead
with a plastic locking tie at the
tape holding the main switch
lead, engine stop switch lead,
clutch switch lead, and start
switch lead together.
ÁPosition the starter cable, throt-
tle cable, CDI magneto lead,
wire harness and rear shock
absorber assembly sub-tank
hose (TT-R125LWE only) as
shown.ÛFasten the wire harness, throttle
cable, starter cable, CDI mag-
neto lead and rear shock
absorber assembly sub-tank
hose (TT-R125LWE only) at the
protecting tube for the CDI mag-
neto lead.
Fasten the rectifier/regulator
lead as shown.
Do not allow the CDI magneto
lead to slacken.
Position the plastic locking tie
ends as shown.
AA
AB
AC
30~35 mm
(1.18~1.38 in)
E
DD
A
C
B-B
D-D
E
B
BC
TT-R125EA
L
1
3
4 2
3
35
3
36
7
3
3
8
9 0 A 3 B C
DEFGHIJKOP
7
4
0
3 3M
N
3Q
3 F
E
DË
◊
„
Ù
AB
AA
Û
ÁAC
N
Ì
Ï ‰ Î
Ç ı Å
Ó
È
Ô

Ò ˜ ˆ Ø ∏
ŒÂÍ ÊÂ