2001 YAMAHA YZ125LC transmission oil

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.,
9Bearings
Pitting/DamageÕReplace.
EC084002
HOW TO READ DESCRIPTIONS
To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each re-
moval and disassembly section.
1. An easy-to-see exploded diagram 1is provided for removal and disassembly jobs.
2. Numbers 2are 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 4accompanies the exploded diagram, providing the order of jobs, names
of parts, notes in jobs, etc.
5. Extent of removal 5is provided in the job instruction chart to save the trouble of an unnecessary
removal job.
6. For jobs requiring more information, the step-by-step format supplements 6are given in addition
to the exploded diagram and job instruction chart.
4-30
ENGCLUTCH AND PRIMARY DRIVEN GEAR
Extent of removal Order Part name Q’ty Remarks
CLUTCH PLATE AND
FRICTION PLATE REMOVAL
Preparation for Drain the transmission oil.
Refer to “TRANSMISSION OIL REPLACE-removalMENT“ section in the CHAPTER 3.Bolt (brake pedal) Shift the brake pedal downward.
Clutch cable Disconnect at engine side.
1 Clutch cover 1
2 Screw (clutch spring) 5
3 Clutch spring 5
4 Pressure plate 1
5 Push rod 1
6 Plain washer 2
7 Bearing 1
8 Friction plate 8
9 Clutch plate 7
Extent of removal:1Clutch plate and friction plate removal
EC490000CLUTCH AND PRIMARY DRIVEN GEAREC498000CLUTCH PLATE AND FRICTION PLATE
1
10 Nm (1.0 m•kg, 7.2 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
4-32
ENGCLUTCH AND PRIMARY DRIVEN GEAREC493000REMOVAL POINTSEC483211Clutch boss1. Remove:
9Nut 1
9Lock washer 2
9Clutch boss 3
NOTE:Straighten the lock washer tab and use the
clutch holding tool 4, 5to hold the clutch boss.
Œ
For USA and CDN
º
Except for USA and CDN
EC494000INSPECTIONEC484100Clutch housing and boss1. Inspect:
9Clutch housing 1
Cracks/Wear/Damage Õ Replace.
9Clutch boss 2
Scoring/Wear/Damage ÕReplace.
EC484201Primary driven gear1. Check:
9Circumferential play
Free play exists ÕReplace.
9Gear teeth a
Wear/ Damage ÕReplace.
EC484400Clutch spring1. Measure:
9Clutch spring free length a
Out of specification ÕReplace springs as
a set.
Clutch holding tool:
YM-91042................................4 4
90890-04086............................5 5
Clutch spring free length:
Standard
40.1 mm 38.1 mm
(1.579 in) (1.500 in)
Œ
ºŒü
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1
2
3
4
56
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EC085002
ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols 1to 7are designed as
thumb tabs to indicate the chapter’s number and
content.
1
General information
2Specifications
3Regular inspection and adjustments
4Engine
5Chassis
6Electrical
7Tuning
Illustrated symbols 8to rare used to identify
the specifications appearing in the text.
8
With engine mounted
9Special tool
0Filling fluid
qLubricant
wTightening
eSpecified value, Service limit
rResistance (½), Voltage (V), Electric current (A)
Illustrated symbols tto oin the exploded dia-
grams indicate grade of lubricant and location of
lubrication point.
t
Apply transmission oil
yApply engine mixing oil
uApply molybdenum disulfide oil
iApply lightweight lithium-soap base grease
oApply molybdenum disulfide grease
Illustrated symbols pto ain the exploded dia-
grams indicate where to apply a locking agent
and where to install new parts.
p
Apply locking agent (LOCTITER)
aUse new one
GEN
INFO
12
3
5
74
6
8
90
qw
er
tyu
io
pa
SPEC
INSP
ADJENG
CHASELEC
TUN
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ABGEBILDETEN SYMBOLE
(Siehe Abbildung)
Die abgebildeten Symbole 1bis 7
sind zur einfachen Auffindung der Sei-
ten mit Daumeneinkerbungen verse-
hen. Die Abschnittsnummer sowie der
lnhalt können sofort ersehen werden.
1Allgemein Angaben
2Technische Daten
3Regelmäßige Prüfung und
Einstellungen
4Motor
5Fahrgestell
6Elektrische Einrichtungen
7Tuning
Die abgebildeten Symbole von 8bis
rwerden zur Unterscheidung der
Spezifikationen in diesem Text
benutzt.
8Mit dem Motor eingebaut
9Spezialwerkzeug
0Einfüllen von Flüssigkeit
qSchmiermittel
wFestziehen (Anzugsmoment)
eVerschleißgrenze, Wartungs-
Toleranzgrenze
rWiderstand (½), Spannung (V),
elektrischer Strom (A)
Die abgebildeten Symbole tbis oin
der Explosionszeichnung zeigen die
Schmierstoffklasse sowie die
Schmierstellen an.
tGetriebeöl auftragen
yMotor-Mischöl auftragen
uMolybdändisulfid-Öl auftragen
iLeichtes Lithium-Fett auftragen
oMolybdändisulfid-Fett auftragen
Die abgebildeten Symbole pbis ain
der Explosionszeichnung zeigen die
Stellen, wo Sicherungslack aufzutra-
gen ist und neue Teile einzubauen
sind.
pSicherungslack (LOCTITE®)
auftragen
aNeues Teil verwenden
SYMBOLES GRAPHIQUES
(Voir l’illustration)
Les symboles graphiques 1à 7ser-
vent à repérer les différents chapitres et
à indiquer leur contenu.
1Renseignements généraux
2Caracteristiques
3Verification et réglages courants
4Moteur
5Partie cycle
6Partie électrique
7Mise au point
Les symboles graphiques 8á rper-
mettent d’identifier les spécifications
encadrées dans le texte.
8Avec de montage du moteur
9Outil spécial
0Liquide de remplissage
qLubrifiant
wSerrage
eValeur spécifiée, limite de service
rRésistance (½), tension (V), intensité (A)
Les symboles graphiques tà odans
les vues éclatées indiquent le grade de
lubrifiant et l’emplacement des points
de lubrification.
tAppliquer de l’huile de transmissionyAppliquer de l’huile de mélange du moteuruAppliquer de l’huile au bisulfure de molybdèneiAppliquer de la graisse fluide à base de savon
au lithium
oAppliquer de la graisse au bisulfure de
molybdène
Les symboles graphiques pet adans
les vues éclatées indiquent où appliquer
de l’agent bloquant et où installer de
nouveaux composants.
pAppliquer un agent de blocage
(LOCTITE®)
aUtiliser une pièce neuve
IC085002
SIMBOLI ILLUSTRATI
(Fare riferimento all’illustra-
zione)
I simboli illustrati da 1a 7sono pro-
gettati come linguette da sfogliare che
indichino il numero e il contenuto del
capitolo.
1Informazioni generali
2Specifiche
3Ispezione e regolazioni regolari
4Motore
5Telaio
6Parte elettrica
7Messa a punto
I simboli illustrati da 8a rvengono
usati per identificare le specifiche che
compaiono nel testo.
8Con motore montato
9Utensile speciale
0Liquido di riempimento
qLubrificante
wSerraggio
eValore specificato, limite di servizio
rResistenza (½), Tensione (V), Corrente
elettrica (A)
I simboli da ta oillustrati nei dia-
grammi esplosi indicano la qualità di
lubrificante e la posizione del punto di
lubrificazione.
tApplicare olio per trasmissioneyApplicare olio per miscela per motoriuApplicare olio a base di bisolfuro di molibdenoiApplicare grasso leggero a base di sapone di
litio
oApplicare grasso a base di bisolfuro di
molibdeno
I simboli pe aillustrati nei diagram-
mi esplosi indicano dove applicare
l’agente bloccante e dove montare il
pezzo di ricambio.
pApplicare agente bloccante
(LOCTITE®)
aUsare un pezzo nuovo
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1-1
GEN
INFO
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1Clutch lever
2”ENGINE STOP” button
3Front brake lever
4Throttle grip
5Radiator cap
6Fuel tank cap
7Kick starter
8Fuel tank
9Radiator
0Coolant drain bolt
qCheck bolt (Transmission oil level)
wRear brake pedal
eValve joint
rFuel cock
tAir cleaner
yDrive chain
uShift pedal
iStarter knob
oFront fork
NOTE:
9The machine you have purchased may differ
slightly from those shown in the following.
9Designs and specifications are subject to
change without notice.
1
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2-1
SPECGENERAL SPECIFICATIONS
Model name: YZ125LC (EUROPE)
YZ125N1 (USA)
YZ125(N) (CDN, AUS, NZ, ZA)
Model code number: 5MV1 (USA, CDN, ZA)
5MV2 (EUROPE)
5MV4 (AUS, NZ)
Dimensions:USA, CDN, ZAEUROPE AUS, NZ
Overall length 2,139 mm 2,136 mm 2,139 mm
(84.2 in) (84.1 in) (84.2 in)
Overall width 827 mm¬¬
(32.6 in)
Overall height 1,318 mm 1,313 mm 1,314 mm
(51.9 in) (51.7 in) (51.7 in)
Seat height 993 mm 994 mm 993mm
(39.1 in) (39.1 in) (39.1 in)
Wheelbase 1,444 mm¬¬
(56.9 in)
Minimum ground clearance 400 mm¬¬
(15.7 in)
Basic weight:
With oil and full fuel tank 95.0 kg (209.4 lb)
Engine:
Engine type Liquid cooled 2-stroke, gasoline
Cylinder arrangement Single cylinder, forward inclined
Displacement 124 cm
3(4.36 lmp oz, 4.19 US oz)
Bore ´Stroke 54 ´54.5 mm (2.126 ´2.146 in)
Compression ratio 8.7~10.8 : 1
Starting system Kick starter
Lubrication system: Premix (30 : 1)(Yamalube 2-R)
Oil type or grade (2-Cycle):
Transmission oil Yamalube 4 (10W-30) or SAE 10W-30 type SE
motor oil
Periodic oil change 0.65 L (0.57 Imp qt, 0.69 US qt)
Total amount 0.70 L (0.62 Imp qt, 0.74 US qt)
Coolant capacity (including all routes): 1.00 L (0.88 Imp qt, 1.06 US qt)
Air filter: Wet type element
Fuel:
Type Except for AUS: Premium unleaded fuel
with a research octane
number of 95 or higher
For AUS: Unleaded fuel only
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
EC200000
SPECIFICATIONSEC211000
GENERAL SPECIFICATIONS
2
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2-2
SPECGENERAL SPECIFICATIONS
Carburetor:
Type/Manufacturer TMXø
38SS/MIKUNI
Spark plug:
Type/Manufacturer BR9EG/NGK
Gap 0.5~0.6 mm (0.020~0.024 in)
Clutch type: Wet, multiple-disc
Transmission:
Primary reduction system Gear
Primary reduction ratio 64/19 (3.368)
Secondary reduction system Chain drive
Secondary reduction ratio 48/13 (3.692)
Transmission type Constant mesh, 6-speed
Operation Left foot operation
Gear ratio: 1st 30/13 (2.307)
2nd 28/15 (1.866)
3rd 26/17 (1.529)
4th 27/21 (1.285)
5th 26/23 (1.130)
6th 24/24 (1.000)
Chassis:USA, CDN, ZA, AUS, NZEUROPE
Frame type Semi double cradle¬
Caster angle 25.6° 25.4°
Trail 107 mm (4.21 in) 104 mm (4.09 in)
Tire:
Type With tube
Size (front) 80/100-21 51M
Size (rear) 100/90-19 57M
Tire pressure (front and rear) 100 kPa (1.0 kg/cm2, 15 psi)
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/Gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto
2
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2-4
SPECMAINTENANCE SPECIFICATIONS
Item Standard Limit
Transmission:
Main axle deflection limit…
0.01 mm (0.0004 in)
Drive axle deflection limit…
0.01 mm (0.0004 in)
Shifter:
Shifting type Cam drum and guide bar…
Guide bar bending limit…
0.05 mm (0.0020 in)
Kick starter type: Kick and mesh type…
Kick clip friction force P=0.8~1.2 kg (1.8~2.6 lb)…
Air filter oil grade (oiled filter):Foam-air-filter oil or engine mixing oil…
Carburetor: USA, CDN, ZA
EUROPE
AUS, NZ
Type/Manufacturer TMXø
38SS¬
/MIKUNI
I.D. mark 5MV1 00 5MV2 10…
Main jet (M.J.) #460 #450…
Jet needle-clip position (J.N.) 6BGK9-75-3 6BHY1-75-3…
Cutaway (C.A.) 5.75¬…
Pilot jet (P.J.) #25 #30…
Pilot air screw (P.A.S.) 1-1/4 1-1/2…
Valve seat size (V.S.)
ø3.8 mm (0.15 in)¬…
Starter jet (G.S.) #80¬…
Fuel level (F.L.) 13.5~14.5 mm ¬
(0.53~0.57 in)
Reed valve:
Thickness* 0.42 mm (0.017 in)…
Valve stopper height 8.2~8.6 mm (0.323~0.339 in)…
Valve bending limit…
0.2 mm (0.008 in)
Cooling:
Radiator core size:
Width 110 mm (4.33 in)…
Height (left) 240 mm (9.45 in)…
(right) 220 mm (8.66 in)…
Thickness 32 mm (1.26 in)…
Radiator cap opening pressure 95~125 kPa…
(0.95~1.25 kg/cm
2, 13.5~17.8 psi)
Radiator capacity (total) 0.63 L (0.55 Imp qt, 0.67 US qt)…
Water pump:
Type Single-suction centrifugal pump…
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2-8
SPECCARACTERISTIQUES D’ENTRETIEN
Article Standard Limite
Roue:
Type de roue avant Roue à rayons…
Type de roue arrière Roue à rayons…
Taille/matériau de jante avant 21 ´1,60/Aluminum…
Taille/matériau de jante arrière 19 ´1,85/Aluminum…
Limite de voile de jante:
Radial…
2,0 mm (0,08 in)
Latéral … 2,0 mm (0,08 in)
Chaîne de transmission:
Type/fabricant DID520DMA2 SDH/DAIDO…
Nombre de maillons 111 maillons+attache…
Flèche de la chaîne 40~50 mm (1,6~2,0 in)…
Longueur de chaîne (10 maillons)…
152,5 mm (6,004 in)
Frein à disque avant:
Dia. extérieur ´épaisseur 250 ´3,0 mm (9,84 ´0,12 in)…
Epaisseur de plaquette 4,4 mm (0,17 in) 1,0 mm (0,04 in)
Dia. intérieur de maître-cylindre 11,0 mm (0,433 in)…
Dia. intérieur de cylindre d’etrier 27,0 mm (1,063 in) ´2…
Type de liquide de frein DOT #4…
Frein à disque arrière:
Dia. extérieur ´épaisseur 240 ´4,0 mm (9,45 ´0,16 in)…
Limite de flèche…
0,15 mm (0,006 in)
Epaisseur de plaquette 6,4 mm (0,25 in) 1,0 mm (0,04 in)
Dia. intérieur de maître-cylindre 12,7 mm (0,500 in)…
Dia. intérieur de cylindre d’etrier 27,0 mm (1,063 in)…
Type de liquide de frein DOT #4…
Levier de frein & pédale de frein:
Position du levier de frein 95 mm (3,74 in)…
Hauteur de la pédale de frein 5 mm (0,20 in)…
(hauteur au-dessus du haut du repose-pied)
Jeu de levier d’embrayage 2~4 mm (0,08~0,16 in)…
(au pivot du levier)
Jeu à la poignée d’accélération 3~5 mm (0,12~0,20 in)…
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