2001 YAMAHA YZ125LC oil type

1-12
GEN
INFO
FUEL AND ENGINE MIXING OIL
EC160050
FUEL AND ENGINE MIXING OIL
Mix oil with the gas at the ratio specified below.
Always use fresh, name-brand gasoline, and mix
the oil and gas the day of the race. Do not use
premix that is more than a few hours old.
NOTE:
Except for AUS:
1. If knocking or pinging occurs, use a different
brand of gasoline or higher octane grade.
2. If unleaded gasoline is not available, then
leaded gasoline can be used.
cC
Never mix two types of oil in the same
batch; clotting of the oil could result. If you
wish to change oil types, be sure to drain
the fuel tank and the carburetor float bowl
of old premix prior to filling with the new
type.
Fuel tank capacity:
8.0 L (1.76 Imp gal, 2.11 US gal)
Mixing oil
Recommended oil:
Yamalube “2-R”
(Yamalube racing 2-cycle oil)
Mixing ratio: 30 : 1
If unavailable, use an equivalent
type of oil.
Recommended fuel:
Except for AUS:
Premium unleaded fuel with
a research octane number of
95 or higher.
For AUS:
Unleaded fuel only
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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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2-7
SPECMAINTENANCE SPECIFICATIONS
EC212201
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing…
Front suspension: USA, CDN, ZA
EUROPE
AUS, NZ
Front fork travel
300 mm (11.8 in)¬…
Fork spring free length
460 mm (18.1 in)¬455 mm (17.9 in)
Spring rate, STD K=4.10 N/mm K=Approx.…
(0.410 kg/mm, 4.10 N/mm
23.0 lb/in) (0.410 kg/mm,
23.0 lb/in)
Optional spring/Spacer Yes¬…
Oil capacity 573 cm
3¬…
(20.2 Imp oz,
19.4 US oz)
Oil level
135 mm (5.31 in)¬…
80~150 mm ¬…
(From top of outer tube with inner tube(3.15~5.91 in)
and damper rod fully compressed
without spring.)
Oil grade Suspension oil ¬…
“01”
Inner tube outer diameter 46 mm (1.81 in)¬…
Front fork top end 5 mm (0.20 in)¬…
Rear suspension: USA, CDN, ZA
EUROPE
AUS, NZ
Shock absorber travel
132 mm (5.20 in)¬…
Spring free length
260 mm (10.24 in) 275 mm (10.83 in)…
Fitting length
248 mm (9.76 in)262 mm (10.31 in)…

242~260 mm 257~275 mm…
(9.53~10.24 in)
(10.12~10.83 in)
Spring rate, STD K=46.0 N/mm K=Approx.…
(4.60 kg/mm, 48.0 N/mm
257.6 lb/in) (4.80 kg/mm,
268.8 lb/in)
Optional spring Yes¬…
Enclosed gas pressure 1,000 kPa ¬…
(10 kg/cm
2,
142 psi)
Swingarm:
Swingarm free play limit
End…
1.0 mm (0.04 in)
Side clearance…
0.2~0.9 mm
(0.008~0.035 in)
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2-11
SPECMAINTENANCE SPECIFICATIONS
EC212300
ELECTRICAL
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Stator M 6 ´1.0 3 8 0.8 5.8
Rotor M10 ´1.25 1 33 3.3 24
Ignition coil M 6 ´1.0 2 7 0.7 5.1
Item Standard Limit
Ignition system:
Ignition timing (B.T.D.C.) 32°/3000 r/min…
0.52 mm (0.020 in)…
Advancer type Electrical…
CDI:
Magneto-model/Manufacturer F4SS00/YAMAHA…
Source coil 1 resistance (color) 720~1,080 ½at 20°C (68°F)…
(Green/White-Black/Red)
Source coil 2 resistance (color) 44~66 ½at 20°C (68°F)…
(Black-Green/Blue)
Pickup coil resistance (color) 248~372 ½at 20°C (68°F)…
(White/Blue-White/Red)
CDI unit-model/Manufacturer 5MV-00/YAMAHA…
Ignition coil:
Model/Manufacturer 4SS-00/YAMAHA…
Minimum spark gap 6 mm (0.24 in)…
Primary winding resistance 0.14~0.20 ½at 20°C (68°F)…
Secondary winding resistance 6.7~10.1k½at 20°C (68°F)…
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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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3-7
INSP
ADJ
RADIATOR CAP INSPECTION
cC
9Do not mix more than one type of ethyl-
ene glycol antifreeze containing corro-
sion inhibitors for aluminum engine.
9Do not use water containing impurities
or oil.
7. Install:
9Radiator cap
Start the engine and warm it up for a sev-
eral minutes.
8. Check:
9Coolant level
Coolant level low ÕAdd coolant.
EC355000
RADIATOR CAP INSPECTION
1. Inspect:
9Seal (radiator cap) 1
9Valve and valve seat 2
Crack/Damage ÕReplace.
Exist fur deposits 3ÕClean or replace.
Handling notes of coolant:
The coolant is harmful so it should be handled
with special care.
w
9When coolant splashes to your eye.
Thoroughly wash your eye with water
and see your doctor.
9When coolant splashes to your clothes.
Quickly wash it away with water and then
with soap.
9When coolant is swallowed.
Quickly make him vomit and take him to
a doctor.
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