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
..................... 1-15
TT-R125
.............................................. 1-15
TT-R125LW
........................................ 1-16
CLEANING AND STORAGE
.................. 1-17
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS
................... 2-1
TT-R125
................................................ 2-1
TT-R125LW
.......................................... 2-4
MAINTENANCE SPECIFICATIONS
......... 2-7
ENGINE
................................................... 2-7
CHASSIS
............................................... 2-15
TT-R125
.............................................. 2-15
TT-R125LW
........................................ 2-19
ELECTRICAL
........................................ 2-23
GENERAL TORQUE
SPECIFICATIONS
.................................. 2-24
DEFINITION OF UNITS
.......................... 2-24
CABLE ROUTING DIAGRAM
................ 2-25
CHAPTER 3
REGULAR INSPECTION AND
ADJUSTMENTS
MAINTENANCE INTERVALS
................... 3-1
PRE-OPERATION INSPECTION
AND MAINTENANCE
............................... 3-3
ENGINE
..................................................... 3-4
CHASSIS
................................................. 3-15
ELECTRICAL
.......................................... 3-29

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
....................................... 4-58
ENGINE REMOVAL
................................ 4-61
CRANKCASE, CRANKSHAFT
AND BALANCER
.................................... 4-65
TRANSMISSION, SHIFT CAM
AND SHIFT FORK
.................................. 4-73
CHAPTER 5
CHASSIS
FRONT WHEEL AND FRONT BRAKE
(TT-R125)
.................................................. 5-1
FRONT WHEEL (TT-R125LW)
................. 5-8
FRONT BRAKE (TT-R125LW)
............... 5-12
REAR WHEEL AND REAR BRAKE
....... 5-24
FRONT FORK
......................................... 5-32
HANDLEBAR
.......................................... 5-41
STEERING
.............................................. 5-49
SWINGARM
............................................ 5-55
REAR SHOCK ABSORBER
ASSEMBLY
............................................. 5-62
CHAPTER 6
ELECTRICAL
ELECTRICAL COMPONENTS
AND WIRING DIAGRAM
.......................... 6-1
IGNITION SYSTEM
................................... 6-2

2 - 25
SPECCABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1Fuel tank breather hose
2CDI unit
3CDI unit band
4Clamp
5CDI magneto lead
6Air vent hose
7Wire harness
8Engine stop switch lead
9Cable guide
0Brake cable
(Brake hose for the
TT-R125LW)
ABrake cable holder
(Brake hose holder for the
TT-R125LW)ÅFit the CDI unit band over the CDI unit bracket till it stops.
ıClamp the ignition coil lead.
ÇClamp the wire harness coupler.
ÎClamp the CDI magneto lead, throttle cable and starter cable.
‰Clamp the CDI magneto lead so that it does not contact the push lever.
ÏPass the air vent hoses between the engine and swingarm.
ÌClamp the wire harness and engine stop switch lead.
ÓPass the brake cable (brake hose for the TT-R125LW) into the cable guide.
ÈClamp the brake cable.
ÔClamp the brake hose between the paint marks.

2 - 26
SPECCABLE ROUTING DIAGRAM
1Air vent hose
2Spark plug lead
3Starter cable
4Throttle cable
5Clutch cable
6Clamp
7Cable guide
8Engine oil breather hose
9Overflow hoseÅAfter clamping the starter cable, push it against the starter plunger.
ıPut the tip of the air vent hose into the main pipe.
ÇInstall the primary coil terminal (orange) to the ignition coil.
ÎFasten the ground lead together with the ignition coil.
‰Pass the clutch cable on the inside of the throttle and starter cable.
ÏClamp the clutch cable with the paint in the cable guide bottom recess.
ÌPass the throttle cable and starter cable into the cable guide.
ÓPass the engine oil breather hose and overflow hose between the right
half of the swingarm and pillar tube.
ÈClamp the engine oil breather hose, overflow hose and air vent hose to
2 clicks.

2 - 27
SPECCABLE ROUTING DIAGRAM
1Engine stop switch lead
2Engine stop switch
3Fuel tank breather hose
4Clamp
5Brake cable
(Brake hose for the TT-R125LW)
6Clutch cable
7Throttle cableÅPass the engine stop switch lead in the middle of the clutch holder.
ıClamp the engine stop switch lead to the handlebar to 3 clicks.
ÇPass the brake cable (brake hose for the TT-R125LW) in front of the
number plate and through the cable guide.
ÎPass the clutch cable in back of the number plate.
‰Insert the fuel tank breather hose into the hole in the starter knob stay
more the 30 mm (1.18 in).
ÏClamp the throttle cable adjuster cover to the handlebar with the clamp
ends downward.