2001 YAMAHA YZ125LC width

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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2-3
SPECMAINTENANCE SPECIFICATIONS
Item Standard Limit
Cylinder head:
Combustion chamber capacity 10.2 cm
3…
(0.359 Imp oz, 0.345 US oz)
Warp limit…
0.03 mm (0.0012 in)
Cylinder:
Bore size 54.000~54.014 mm 54.1 mm (2.130 in)
(2.1260~2.1265 in)
Taper limit…
0.05 mm (0.0020 in)
Out of round limit…
0.01 mm (0.0004 in)
Piston:
Piston size/ 53.957~53.972 mm…
(2.1243~2.1249 in)
Measuring point* 17.5 mm (0.69 in)…
Piston clearance 0.040~0.045 mm 0.1 mm (0.004 in)
(0.0016~0.0018 in)
Piston offset 1.0 mm (0.039 in)/EX-side…
Piston pin:
Piston pin outside diameter 14.995~15.000 mm 14.975 mm
(0.5904~0.5906 in) (0.5896 in)
Piston ring:
Sectional sketch Plain…
B=1.0 mm (0.039 in)…
T=2.15 mm (0.085 in)…
End gap (installed) 0.5~0.7 mm (0.020~0.028 in) 1.2 mm (0.047 in)
Side clearance (installed) 0.035~0.080 mm 0.1 mm (0.004 in)
(0.0014~0.0031 in)
Crankshaft:
Crank width “A” 55.90~55.95 mm …
(2.201~2.203 in)
Runout limit “C” 0.03 mm (0.0012 in) 0.05 mm (0.0020 in)
Connecting rod big end
side clearance “D” 0.20~0.70 mm (0.008~0.028 in)…
Small end free play “F” 0.8~1.0 mm (0.031~0.039 in) 2.0 mm (0.08 in)
Clutch:
Friction plate thickness 2.9~3.1 mm (0.114~0.122 in) 2.8 mm (0.110 in)
Quantity 8 …
Clutch plate thickness 1.5~1.7 mm (0.059~0.067 in) …
Quantity 7 …
Warp limit … 0.2 mm (0.008 in)
Clutch spring free length 40.1 mm (1.579 in) 38.1 mm (1.500 in)
Quantity 5 …
Clutch housing thrust clearance 0.20~0.25 mm (0.008~0.010 in) …
Clutch housing radial clearance 0.015~0.049 mm …
(0.0006~0.0019 in)
Clutch release method Outer pull, rack and pinion pull …
EC212000
MAINTENANCE SPECIFICATIONSEC212100
ENGINE
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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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4-50
ENGWATER PUMP
EC4G3000
REMOVAL POINTS
EC4G3110
Impeller shaft
1. Remove:
9Impeller 1
9Plain washer 2
9Impeller shaft 3
NOTE:
Hold the impeller shaft on its width across the
flats awith spanners, etc. and remove the im-
peller.
EC4G3210
Oil seal
NOTE:
It is not necessary to disassemble the water
pump, unless there is an abnormality such as
excessive change in coolant level, discoloration
of coolant, or milky transmission oil.
1. Remove:
9Bearing 1
2. Remove:
9Oil seal 1
EC4G4000
INSPECTIONEC444200
Impeller shaft
1. Inspect:
9Impeller shaft 1
Bend/Wear/Damage ÕReplace.
Fur deposits ÕClean.
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4-52
ENGWATER PUMP
EC4G5220
Impeller shaft
1. Install:
9Impeller shaft 1
NOTE:
9Take care so that the oil seal lip is not dam-
aged or the spring does not slip off its position.
9When installing the impeller shaft, apply the
lithium soap base grease on the oil seal lip and
impeller shaft. And install the shaft while turn-
ing it.
2. Install:
9Plain washer 1
9Impeller 2
NOTE:
Hold the impeller shaft on its width across the
flats awith spanners, etc. and install the im-
peller.
3. Install:
9Dowel pin 1
9Gasket (water pump housing cover) 2
4. Install:
9Water pump housing cover 1
9Bolt (water pump housing cover) 2
9Copper washer (coolant drain bolt) 3
9Coolant drain bolt 4
10 Nm (1.0 m•kg, 7.2 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
14 Nm (1.4 m•kg, 10 ft•lb)
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4-65
ENGCRANKCASE AND CRANKSHAFT
Standard
Runout 0.03 mm 0.05 mm
limit: (0.0012 in) (0.0020 in)
Small end 0.8~1.0 mm 2.0 mm
free play: (0.031~0.039 in) (0.08 in)
Side 0.20~0.70 mm
—
clearance: (0.008~0.028in)
Crank 55.90~55.95 mm
—
width: (2.201~2.203 in)
2. Inspect:
9Bearings 1
Rotate inner race with a finger.
Rough spot/Seizure ÕReplace.
3. Inspect:
9Oil seal 1
Damage ÕReplace.
EC4N4202
Crankshaft
1. Measure:
9Runout limit a
9Small end free play limit b
9Connecting rod big end side clearance c
9Crank width d
Out of specification ÕReplace.
Use the dial gauge and a thickness gauge.
EC4N5000
ASSEMBLY AND INSTALLATION
EC4N5300
Crankshaft bearing
1. Install:
9Bearing 1
To crankcase (left and right).
NOTE:
Install the bearing by pressing its outer race
parallel.
Dial gauge:
YU-3097/90890-01252
5MV-9-30-4D 6/19/00 1:39 PM Page 18