YAMAHA YZ250LC 2001 Manuale duso (in Italian)

2-4
MAINTENANCE SPECIFICATIONSSPEC
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 ratchet type…
Air filter oil grade (oiled filter):Foam-air-filter oil or engine mixing oil…
Carburetor:USA, CDN, ZA,
EUROPE
AUS, NZ
Type/Manufacturer
PWK38S/KEIHIN¬…
I.D. mark 5MW00 5MW10…
Main jet (M.J.) #178 #180…
Main air jet (M.A.J) #200¬…
Jet needle-clip position (J.N.) N3EJ-2 N3CW-3…
Main nozzle (N.J.) ø2.9¬…
Cutaway (C.A.) #7¬…
Pilot jet (P.J.) #50 #55…
Pilot air screw (P.A.S.) 1 1-3/4…
(for reference only)
Valve seat size (V.S.)
ø3,8 mm (0,15 in)¬…
Starter jet (G.S.) #85¬…
Power jet (P.W.J.) #50 #55 …
Float arm height (F.H.) 5.5~7.5 mm¬…
(0.22~030 in)
Reed valve:
Thickness* 0.42 mm (0.017 in)…
Valve stopper height 10.3~10.7 mm (0.406~0.421 in)…
Valve bending limit…
0.2 mm (0.008 in)
Cooling:
Radiator core size:
Width 110 mm (4.33 in)…
Height 240 mm (9.45 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) 0.64 L (0.56 Imp qt, 0.68 US qt)…
Water pump:
Type Single-suction centrifugal pump…
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2-5
MAINTENANCE SPECIFICATIONSSPEC
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Spark plug M14 ´1.25 1 20 2.0 14
Cylinder head (nut) M 8 ´1.25 6 25 2.5 18
(stud) M 8 ´1.25 6 13 1.3 9.4
Cylinder (nut) M10 ´1.25 4 35 3.5 25
(stud) M10 ´1.25 4 13 1.3 9.4
Power valve :
Holder M 5 ´0.8 2 6 0.6 4.3
Link rod M 5 ´0.8 2 6 0.6 4.3
Push rod M 5 ´0.8 1 5 0.5 3.6
Thrust plate M 5 ´0.8 1 6 0.6 4.3
Side holder M 5 ´0.8 4 4 0.4 2.9
Link lever M 4 ´0.7 1 4 0.4 2.9
Pulley M 4 ´0.7 2 4 0.4 2.9
Cover M 5 ´0.8 4 4 0.4 2.9
Governor fork M 4 ´0.7 2 5 0.5 3.6
Housing M 5 ´0.8 4 5 0.5 3.6
Impeller M 8 ´1.25 1 14 1.4 10
Water pump housing cover M 6 ´1.0 4 10 1.0 7.2
Coolant drain bolt M 6 ´1.0 1 10 1.0 7.2
Radiator M 6 ´1.0 6 10 1.0 7.2
Radiator hose clamp M 6 ´1.0 8 1 0.1 0.7
Air filter element M 6 ´1.0 1 2 0.2 1.4
Carburetor joint M 6 ´1.0 5 10 1.0 7.2
Air filter case M 6 ´1.0 2 4 0.4 2.9
Air filter joint M 5 ´0.8 5 1 0.1 0.7
Reed valve M 3 ´0.5 4 1 0.1 0.7
Exhaust pipe M 6 ´1.0 2 12 1.2 8.7
Exhaust pipe stay (front) M 8 ´1.25 1 25 2.5 18
Exhaust pipe stay (rear) M 6 ´1.0 1 12 1.2 8.7
Silencer (front) M 6 ´1.0 1 12 1.2 8.7
Silencer (rear) M 6 ´1.0 1 7 0.7 5.1
Fiber (silencer) M 6 ´1.0 2 10 1.0 7.2
Crankcase M 6 ´1.0 11 14 1.4 10
Crankcase cover (left) M 6 ´1.0 5 8 0.8 5.8
Chain cover M 6 ´1.0 2 8 0.8 5.8
Crankcase cover (right) M 6 ´1.0 9 10 1.0 7.2
Bearing plate cover (drive axle left) M 6 ´1.0 2 10 1.0 7.2
Bearing plate cover (main axle right) M 6 ´1.0 2 10 1.0 7.2
Holder M 6 ´1.0 2 10 1.0 7.2
Oil drain bolt M12 ´1.5 1 20 2.0 14
Oil check bolt M 6 ´1.0 1 10 1.0 7.2
Kick starter M 8 ´1.25 1 30 3.0 22
Ratchet wheel stopper M 6 ´1.0 2 10 1.0 7.2
Clutch cover M 6 ´1.0 6 10 1.0 7.2
Primary drive gear M10 ´1.25 1 55 5.5 40
Clutch boss M20 ´1.0 1 75 7.5 54
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2-6
MAINTENANCE SPECIFICATIONSSPEC
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Clutch spring M 6 ´1.0 6 10 1.0 7.2
Push lever axle M 5 ´0.8 1 6 0.6 4.3
Drive sprocket M20 ´1.0 1 75 7.5 54
Shift guide M 6 ´1.0 2 10 1.0 7.2
Stopper lever M 6 ´1.0 1 10 1.0 7.2
Torsion spring (shift shaft) stopper bolt M 8 ´1.25 1 22 2.2 16
Segment M 8 ´1.25 1 30 3.0 22
Bearing plate cover (shift cam right) M 6 ´1.0 2 10 1.0 7.2
Shift pedal M 6 ´1.0 1 10 1.0 7.2
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2-7
MAINTENANCE SPECIFICATIONSSPEC
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=4.30 N/mm
K=Approx. 4.30 N/mm…
(0.430 kg/mm, (0.430 kg/mm)
24.1 lb/in) 24.1 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 endZero mm (Zero 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
244 mm (9.61 in)267 mm (10.51 in)…

242~260 mm 257~275 mm…
(9.53~10.24 in) (10.12~10.83 in)
Spring rate, STD K=48 N/mm K=Approx. 50 N/mm…
(4.8 kg/mm, (5.0 kg/mm,
269 lb/in) 280 lb/in)
Optional spring Yes¬…
Enclosed gas pressure
1,000 kPa¬…
(10 kg/cm2, 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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2-8
MAINTENANCE SPECIFICATIONSSPEC
Item Standard Limit
Wheel:
Front wheel type Spoke wheel…
Rear wheel type Spoke wheel…
Front rim size/Material 21 ´1.60/Aluminum…
Rear rim size/Material 19 ´2.15/Aluminum…
Rim runout limit:
Radial…
2.0 mm (0.08 in)
Lateral…
2.0 mm (0.08 in)
Drive chain
Type/Manufacturer DID520DMA2 SDH/DAIDO…
Number of links 113 links + joint…
Chain slack 40~50 mm (1.6~2.0 in)…
Chain length (10 links)…
152.5 mm (6.004 in)
Front disc brake:
Disc outside dia. ´Thickness 250 ´3.0 mm (9.84 ´0.12 in)…
Pad thickness 4.4 mm (0.17 in) 1.0 mm (0.04 in)
Master cylinder inside dia. 11.0 mm (0.433 in)…
Caliper cylinder inside dia. 27.0 mm (1.063 in) ´2…
Brake fluid type DOT #4…
Rear disc brake:
Disc outside dia. ´Thickness 240 ´4.0 mm (9.45 ´0.16 in)…
Deflection limit…
0.15 mm (0.006 in)
Pad thickness 6.4 mm (0.25 in) 1.0 mm (0.04 in)
Master cylinder inside dia. 12.7 mm (0.500 in)…
Caliper cylinder insdie dia. 27.0 mm (1.063 in)…
Brake fluid type DOT #4…
Brake lever & brake pedal:
Brake lever position 95 mm (3.74 in)…
Brake pedal height 5 mm (0.20 in)…
(vertical height above footrest top)
Clutch lever free play (at lever pivot) 2~4 mm (0.08~0.16 in)…
Throttle grip free play 3~5 mm (0.12~0.20 in)…
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2-9
MAINTENANCE SPECIFICATIONSSPEC
17
14
105
20
22
40
21
0.7
7.2
7.2
11
5.1
0.7
2.9
1.4
2.9
6.5
1.4
4.3
4.3
3.6
2.9
22
22
17
2.2
13
4.3
75
17
8.7
10
19
7.2M 8 ´ 1.25
M 8 ´ 1.25
M24 ´ 1.0
M 8 ´ 1.25
M28 ´ 1.0
M48 ´ 1.0
M30 ´ 1.0
M12 ´ 1.25
M 5 ´ 0.8
M 6 ´ 1.0
M 6 ´ 1.0
M 8 ´ 1.25
M 6 ´ 1.0
M 4 ´ 0.7
M 6 ´ 1.0
M 6 ´ 1.0
M 5 ´ 0.8
M 6 ´ 1.0
M 4 ´ 0.7
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 5 ´ 0.8
M10 ´ 1.25
M10 ´ 1.25
M 8 ´ 1.25
M10 ´ 1.0
M10 ´ 1.0
M 8 ´ 1.25
M16 ´ 1.5
M 8 ´ 1.25
M 6 ´ 1.0
M 6 ´ 1.0
M 8 ´ 1.25
M 6 ´ 1.0 Handle crown and outer tube
Under bracket and outer tube
Handle crown and steering shaft
Handlebar holder (upper)
Steering ring nut
Front fork and cap bolt
Front fork and base valve
Cap bolt and damper rod (front fork)
Bleed screw (front fork) and cap bolt
Front fork and protector
Front fork and brake hose holder
Front fork and hose cover
Front fork and hose cover
Throttle cable cap
Grip cap upper and lower
Clutch lever (bolt)
Clutch lever holder
Front brake master cylinder and bracket
Front brake master cylinder cap
Brake lever mounting (bolt)
Brake lever mounting (nut)
Brake lever position locknut
Cable guide (front brake hose) and guide stay
Front brake hose union bolt (master cylinder)
Front brake hose union bolt (caliper)
Front brake caliper and front fork
Brake caliper (front and rear) and pad pin plug
Brake caliper (front and rear) and pad pin
Brake caliper (front and rear) and bleed screw
Front wheel axle and nut
Front wheel axle holder
Front brake disc and wheel hub
Rear brake disc and wheel hub
Brake pedal mounting
Rear brake master cylinder and framePart to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
4
4
1
4
1
2
2
2
2
6
2
1
1
2
2
1
2
2
2
1
1
1
1
1
1
2
1
1
1
1
4
6
6
1
223
20
145
28
30
55
29
1
10
10
16
7
1
4
2
4
9
2
6
6
5
4
30
30
23
3
18
6
105
23
12
14
26
102.3
2.0
14.5
2.8
3.0
5.5
2.9
0.1
1.0
1.0
1.6
0.7
0.1
0.4
0.2
0.4
0.9
0.2
0.6
0.6
0.5
0.4
3.0
3.0
2.3
0.3
1.8
0.6
10.5
2.3
1.2
1.4
2.6
1.0
NOTE:
1. First, tighten the ring nut approximately 38 Nm (3.8 m•kg, 27 ft•lb) by using the ring nut wrench,
then loosen the ring nut one turn.
2. Retighten the ring nut 7 Nm (0.7 m•kg, 5.1 ft•lb).
Refer to NOTE
5MW-9-30-2 7/3/00 2:20 PM Page 10

2-10
MAINTENANCE SPECIFICATIONSSPEC
M 6 ´ 1.0
M10 ´ 1.25
M10 ´ 1.25
M20 ´ 1.5
M 8 ´ 1.25
–
M 6 ´ 1.0
M 6 ´ 1.0
M 8 ´ 1.25
M10 ´ 1.25
M10 ´ 1.25
M10 ´ 1.25
M16 ´ 1.5
M14 ´ 1.5
M14 ´ 1.5
M14 ´ 1.5
M10 ´ 1.25
M10 ´ 1.25
M 8 ´ 1.25
M 5 ´ –
M 8 ´ 1.25
M 6 ´ 1.0
M 5 ´0.8
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0
M 6 ´ 1.0 Rear brake reservoir tank and frame
Rear brake hose union bolt (caliper)
Rear brake hose union bolt (master cylinder)
Rear wheel axle and nut
Driven sprocket and wheel hub
Nipple (spoke)
Disc cover and rear brake caliper
Protector and rear brake caliper
Engine mounting:
Engine bracket and frame
Engine and frame (front)
Engine and frame (upper)
Engine and frame (lower)
Pivot shaft and nut
Relay arm and swingarm
Relay arm and connecting rod
Connecting rod and frame
Rear shock absorber and frame
Rear shock absorber and relay arm
Rear frame and frame
Swingarm and brake hose holder
Drive chain tensioner mounting
Chain support and swingarm
Seal guard and swingarm
Fuel tank mounting
Fuel tank and fuel cock
Fuel tank and seat set bracket
Fuel tank and hooking screw (fitting band)
Fuel tank and fuel tank bracket
Seat mounting
Side cover mounting
Air scoop mounting
Front fender mounting
Rear fender mounting
Number platePart to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
1
1
1
1
6
72
2
2
2
1
1
1
1
1
1
1
1
1
3
4
2
3
4
2
2
1
1
4
2
4
8
4
4
17
30
30
125
42
3
7
7
34
69
69
69
85
80
80
80
56
53
29
4
19
7
5
10
7
7
7
7
7
7
3
7
7
70.7
3.0
3.0
12.5
4.2
0.3
0.7
0.7
3.4
6.9
6.9
6.9
8.5
8.0
8.0
8.0
5.6
5.3
2.9
0.4
1.9
0.7
0.5
1.0
0.7
0.7
0.7
0.7
0.7
0.7
0.3
0.7
0.7
0.75.1
22
22
90
30
2.2
5.1
5.1
24
50
50
50
61
58
58
58
40
38
21
2.9
13
5.1
3.6
7.2
5.1
5.1
5.1
5.1
5.1
5.1
2.2
5.1
5.1
5.1
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.
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2-11
MAINTENANCE SPECIFICATIONSSPEC
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 41 4.1 30
Ignition coil M 6 ´1.0 2 7 0.7 5.1
Item Standard Limit
Ignition system:
Ignition timing (B.T.D.C.) 0.18 mm (0.007 in)…
Advancer type Electrical…
CDI:
Magneto-model/Manufacturer F5CU10/YAMAHA…
Source coil 1 resistance (color) 720~1,080 ½at 20°C (68°F)…
(Black-Black/Red)
Source coil 2 resistance (color) 44~66 ½at 20°C (68°F)…
(Green/Blue-Green/White)
Pickup coil resistance (color) 248~372 ½at 20°C (68°F)…
(White/Blue-White/Red)
CDI unit-model/Manufacturer 5HC-00/YAMAHA…
Ignition coil:
Model/Manufacturer 5BE-00/YAMAHA…
Minimum spark gap 6 mm (0.24 in)…
Primary winding resistance 0.20~0.30 ½at 20°C (68°F)…
Secondary winding resistance 9.5~14.3 k½at 20°C (68°F)…
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2-12
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
SPEC
This chart specifies torque for standard faste-
ners with standard I.S.O. pitch threads. Torque
specifications for special components or assem-
blies are included in the applicable sections of
this book. To avoid warpage, tighten multi-faste-
ner assemblies in a crisscross fashion, in pro-
gressive stages, until full torque is reached.
Unless otherwise specified, torque specifications
call for clean, dry threads. Components should
be at room temperature.
A: Distance across flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
EC220001
GENERAL TORQUE SPECIFICATIONS
ABTORQUE SPECIFICATION
(Nut) (Bolt)
Nm m•kg ft•lb
10 mm 6 mm 6 0.6 4.3
12 mm 8 mm 15 1.5 11
14 mm 10 mm 30 3.0 22
17 mm 12 mm 55 5.5 40
19 mm 14 mm 85 8.5 61
22 mm 16 mm 130 13 94
Unit Read Definition Measure
mm milimeter 10-
3meter Length
cm centimeter 10-2meter Length
kg kilogram 103gram Weight
N Newton 1 kg ´m/sec2Force
Nm Newton meter N ´m Torque
m•kg Meter kilogrma m ´kg Torque
Pa Pascal N/m2Pressure
N/mm Newton per millimeter N/mm Spring rate
L Liter — Volume or capacity
cm3Cubic centimeter — Volume or capacity
r/min Revolution per minute — Engine speed
5MW-9-30-2 7/3/00 2:20 PM Page 13

2-1
CARACTERISTIQUES GENERALESSPEC
Nom de modèle: YZ250LC (EUROPE)
YZ250N1 (USA)
YZ250(N) (CDN, AUS, NZ, ZA)
Numéro de code de modèle: 5MW1 (USA, CDN, ZA)
5MW2 (EUROPE)
5MW4 (AUS, NZ)
Dimensions: USA, CDN, ZA EUROPE AUS, NZ
Longueur hors-tout 2.179 mm 2.178 mm 2.179 mm
(85,8 in) (85,7 in) (85,8 in)
Largeur hors-tout 827 mm¬¬
(32,6 in)
Hauteur hors-tout 1.307 mm 1.302 mm 1.303 mm
(51,5 in) (51,3 in) (51,3 in)
Hauteur de la selle 989 mm¬¬
(38,9 in)
Empattement 1.482 mm¬¬
(58,3 in)
Garde au sol minimale 392 mm 391 mm 392 mm
(15,4 in) (15,4 in) (15,4 in)
Poids en ordre de marche:
Avec plein d’huile et de carburant 104,5 kg (230 lb)
Moteur:
Type de moteur 2-temps, essence, refroidissement liquide
Dispositions de cylindres Monocylindre, incliné
Cylindrée 249 cm
3(8,76 lmp oz, 8,42 US oz)
Alésage ´course 66,4 ´72 mm (2,614 ´2,835 in)
Taux de compression 9,1~10,6 : 1
Système de démarrage Démarreur au pied
Système de graissage: Mélange (30 : 1)(Yamalube 2-R)
Type ou grade d’huile (2-temps):
Huile de transmission Huile Yamalube 4 (10W-30) ou huile moteur
SAE 10W-30 type SE
Vidange périodique 0,75 L (0,66 Imp qt, 0,79 US qt)
Quantité totale 0,80 L (0,70 Imp qt, 0,85 US qt)
Capacité de liquide de refroidissement
(Toutes les tuyauteries comprises): 1,20 L (1,06 Imp qt, 1,27 US qt)
Filtre à air: Elément type humide
Essence:
Type Excepté pour AUS: Essence super sans plomb d’un
indice d’octane de recherche 95
ou plus
Pour AUS: Uniquement essence sans plomb
Capacité du réservoir 8,0 L (1,76 Imp gal, 2,11 US gal)
CARACTERISTIQUES
CARACTERISTIQUES GENERALES
5MW-9-30-2 7/3/00 2:20 PM Page 14