2006 YAMAHA YZ250LC engine

2-1
GENERAL SPECIFICATIONSSPEC
Model name: YZ250V (USA, CDN)
YZ250 (EUROPE, ZA)
YZ250V (AUS, NZ)
Model code number: 1P85 (USA, CDN)
1P86 (EUROPE)
1P88 (AUS, NZ, ZA)
Dimensions:USA, AUS, NZ, ZACDN EUROPE
Overall length 2,178 mm 2,182 mm 2,184 mm
(85.7 in) (85.9 in) (86.0 in)
Overall width 827 mm←←
(32.6 in)
Overall height 1,305 mm 1,308 mm 1,309 mm
(51.4 in) (51.5 in) (51.5 in)
Seat height 994 mm 996 mm 997 mm
(39.1 in) (39.2 in) (39.3 in)
Wheelbase 1,481 mm←←
(58.3 in)
Minimum ground clearance 382 mm 384 mm 385 mm
(15.0 in) (15.1 in) (15.2 in)
Dry weight:
Without oil and fuel 96.0 kg (211.6 lb)
Engine:
Engine type Liquid cooled 2-stroke, gasoline
Cylinder arrangement Single cylinder, forward inclined
Displacement 249 cm
3(8.76 lmp oz, 8.42 US oz)
Bore ×Stroke 66.4 ×72 mm (2.614 ×2.835 in)
Compression ratio 9.2~10.9 : 1 (For USA and CDN)
8.9~10.6 : 1 (For EUROPE, AUS, NZ and ZA)
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 0.75 L (0.66 Imp qt, 0.79 US qt)
Total amount 0.80 L (0.70 Imp qt, 0.85 US qt)
Coolant capacity (including all routes): 1.20 L (1.06 Imp qt, 1.27 US qt)
Air filter: Wet type element
Fuel:
Type Premium unleaded gasoline
only with a research octane
number of 95 or higher
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
EC200000
SPECIFICATIONSEC211000
GENERAL SPECIFICATIONS
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2-3
MAINTENANCE SPECIFICATIONSSPEC
Item Standard Limit
Cylinder head:
USA, CDNEUROPE,
AUS, NZ, ZA
Combustion chamber capacity 21.0 cm
321.5 cm3…
(0.739 Imp oz, (0.757 Imp oz,
0.710 US oz) 0.727 US oz)
Warp limit……
0.03 mm (0.0012 in)
Cylinder:
Bore size 66.400~66.414 mm 66.5 mm (2.618 in)
(2.6142~2.6147 in)
Taper limit…
0.05 mm (0.0020 in)
Out of round limit…
0.01 mm (0.0004 in)
Piston:
Piston size/ 66.352~66.367 mm…
(2.6120~2.6129 in)
Measuring point* 17.5 mm (0.69 in)…
Piston clearance 0.045~0.050 mm 0.1 mm (0.004 in)
(0.0018~0.0020 in)
Piston offset 1.5 mm (0.059 in)/EX-side…
Piston pin:
Piston pin outside diameter 17.995~18.000 mm 17.975 mm
(0.7085~0.7087 in) (0.7077 in)
Piston ring:
Sectional sketch Plain…
B=1.0 mm (0.039 in)…
T=2.55 mm (0.100 in)…
End gap (installed) 0.40~0.55 mm (0.016~0.022 in) 0.95 mm (0.037 in)
Side clearance (installed) : 1st
0.030~0.065 mm (0.0012~0.0026 in)0.1 mm (0.004 in)
: 2nd0.030~0.065 mm (0.0012~0.0026 in)0.1 mm (0.004 in)
Crankshaft:
Crank width “A” 59.95~60.00 mm (2.360~2.362 in)…
Runout limit “C” 0.03 mm (0.0012 in) 0.05 mm (0.0020 in)
Connecting rod big end
side clearance “D” 0.25~0.75 mm (0.010~0.030 in)…
Small end free play “F” 0.4~1.0 mm (0.016~0.039 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 50.0 mm (1.969 in) 48.0 mm (1.890 in)
Quantity 6 …
EC212000
MAINTENANCE SPECIFICATIONSEC212100
ENGINE
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2-10
MAINTENANCE SPECIFICATIONSSPEC
M 4 × 0.7
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
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 8 × 1.25
M 5 ×0.8
M 4 ×0.7
M 8 × 1.25
M 6 × 1.0
M 5 ×0.8
M 5 ×0.8
M10 × 1.25
M 6 × 1.0
M 6 × 1.0
M 6 × 1.0
M 6 × 1.0
M 6 × 1.0
M 8 × 1.25
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 master cylinder cap
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
Chain puller adjust bolt and locknut
Engine mounting:
Engine bracket and frame
Engine and frame (front)
Engine bracket and engine
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 (upper)
Rear frame and frame (lower)
Swingarm and brake hose holder
Swingarm and patch
Drive chain tensioner mounting
Chain support and swingarm
Seal guard and swingarm
Cable guide and frame
Fuel tank mounting boss and frame
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 and fuel tank
Air scoop and panel
Front fender mounting
Rear fender mounting (front)
Rear fender mounting (rear)
Number platePart to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
2
1
1
1
6
72
2
2
2
2
1
1
1
1
1
1
1
1
1
1
2
4
4
2
3
4
2
2
2
2
1
1
4
2
2
4
2
4
2
2
12
30
30
125
42
3
10
7
16
34
64
64
64
85
70
80
80
56
53
32
29
2
2
16
7
6
4
20
10
7
7
7
7
19
7
7
6
7
7
12
70.2
3.0
3.0
12.5
4.2
0.3
1.0
0.7
1.6
3.4
6.4
6.4
6.4
8.5
7.0
8.0
8.0
5.6
5.3
3.2
2.9
0.2
0.2
1.6
0.7
0.6
0.4
2.0
1.0
0.7
0.7
0.7
0.7
1.9
0.7
0.7
0.6
0.7
0.7
1.2
0.71.4
22
22
90
30
2.2
7.2
5.1
11
24
46
46
46
61
50
58
58
40
38
23
21
1.4
1.4
11
5.1
4.3
2.9
14
7.2
5.1
5.1
5.1
5.1
13
5.1
5.1
4.3
5.1
5.1
8.7
5.1
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.
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2-13
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
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2-14
CABLE ROUTING DIAGRAMSPEC
EC240000
CABLE ROUTING DIAGRAM
1“ENGINE STOP” button lead
2Throttle cable
3Clutch cable
4Clamp
5Wireharness
6Radiator breather hose
7Air vent hose
8Crankcase breather hose
9Overflow hoseAPass the clutch cable on the
outside of the throttle cable and
“ENGINE STOP” button lead.
BAlign the throttle cable locating
tape with the cable guide.
CPass the throttle cable, clutch
cable and “ENGINE STOP” but-
ton lead above the radiator
hose.
DClamp the “ENGINE STOP” but-
ton lead to the frame. Tighten
the clamp so that the “ENGINE
STOP” button lead is not pulled
when the handlebar is turned to
the right and left.
EClamp the throttle cable, clutch
cable and wireharness to the
frame.
FClamp the throttle cable and
wireharness to the frame.GPass the clutch cable in front of
the center of the cylinder head
tightening nut.
HPass the air vent hose, overflow
hose and crankcase breather
hose between the frame and
connecting rod.
ILocate the clamp ends in the
arrowed range.
JPass the throttle cable behind
the air vent hose.
KPass the air vent hose, overflow
hose and crankcase breather
hose so that they do not contact
the rear shock absorber.
LClamp the air vent hoses.
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2-14
SCHEMA DE CHEMINEMENT DES CABLES
KABELFÜHRUNGSÜBERSICHTPLAN
DIAGRAMMA DEL PASSAGGIO DEI CAVISPEC
KABELFÜHRUNGSÜBER-
SICHTPLAN
1ENGINE STOP“-Schalterkabel
2Gaszug
3Kupplungszug
4Klemme
5Kabelbaum
6Kühler-Entlüftungsschlauch
7Belüftungsschlauch
8Kurbelgehäuse-Entlüftungsschlauch
9Überlaufschlauch
ADen Kupplungszug außen am Gaszug
und am „ENGINE STOP“-Schalterkabel
entlangführen.
BDas Gaszug-Lokalisierungsband an der
Kabelführung ausrichten.
CDen Gaszug, den Kupplungszug und
das „ENGINE STOP“-Schalterkabel
über dem Kühlerschlauch entlang-
führen.
DDas „ENGINE STOP“-Schalterkabel am
Rahmen festklammern. Die Klemme
festziehen, damit nicht am „ENGINE
STOP“-Schalterkabel gezogen werden
kann, wenn der Lenker nach rechts
oder nach links bewegt wird.
EDen Gaszug, den Kupplungszug und
den Kabelbaum am Rahmen festklam-
mern.
FDen Gaszug und den Kabelbaum am
Rahmen festklammern.
GDen Kupplungszug vor der Mitte der
Zylinderkopf-Anzugsmutter entlang-
führen.
HDen Belüftungsschlauch, den Überlauf-
schlauch und den Kurbelgehäuse-Ent-
lüftungsschlauch zwischen dem Rah-
men und dem Pleuel entlangführen.
IDie Klemmenenden im zulässigen
Bereich anbringen.
JDen Gaszug hinter dem Belüftungs-
schlauch entlangführen.
KDen Belüftungsschlauch, den Überlauf-
schlauch und den Kurbelgehäuse-Ent-
lüftungsschlauch so entlangführen,
dass sie keinerlei Kontakt zum hinteren
Stoßdämpfer haben.
LDie Belüftungsschläuche festklammern.
SCHEMA DE
CHEMINEMENT DES
CABLES
1Fil du bouton “ENGINE STOP” 2Câble des gaz3Câble d’embrayage4Collier5Faisceau de fils6Durit de mise à l’air du radiateur7Durit de ventilation8Durit de mise à l’air du carter moteur9Durit de trop-plein
AFaire passer le câble d’embrayage à
l’extérieur du câble des gaz et du fil du
bouton “ENGINE STOP”.
BAligner la bande de positionnement du
câble des gaz sur le guide du câble.
CFaire passer le câble des gaz, le câble
d’embrayage et le fil du bouton “ENGI-
NE STOP” au-dessus de la durit de mise
à l’air du radiateur.
DBrider le fil du bouton “ENGINE STOP”
au cadre. Serrer le collier à pince de
façon à ce que le fil du bouton “ENGINE
STOP” ne soit pas tiré lorsque le guidon
tourne vers la gauche et vers la droite.
EBrider le câble des gaz, le câble
d’embrayage et le faisceau de fils au
cadre.
FBrider le câble des gaz et le faisceau de
fils au cadre.
GFaire passer le câble d’embrayage devant
le centre de l’écrou de serrage de la
culasse.
HFaire passer la durit de ventilation, la
durit de trop-plein et la durit de mise à
l’air du carter moteur entre le cadre et la
bielle.
IPlacer les extrémités du collier dans le
sens de la flèche.
JFaire passer le câble des gaz derrière la
durit de ventilation.
KFaire passer la durit de ventilation, la
durit de trop-plein et la durit de mise à
l’air du carter moteur de façon à ce
qu’elles ne soient pas en contact avec
l’amortisseur arrière.
LBrider les durits de ventilation.
IC240000
DIAGRAMMA DEL
PASSAGGIO DEI CAVI
1Conduttore del pulsante “ARRESTO
MOTORE”
2Cavo acceleratore3Cavo frizione4Morsetto5Cablaggio elettrico 6Flessibile di sfiato del radiatore7Flessibile di sfiato aria8Tubo di sfiato del carter9Flessibile di troppopieno carburante
AFar passare il cavo della frizione dal lato
esterno del cavo dell’acceleratore e del
conduttore del pulsante “ARRESTO
MOTORE”.
BAllineare il nastro di posizione del cavo
acceleratore con la guida per cavi.
CFar passare il cavo dell’acceleratore, il
cavo della frizione e il conduttore del
pulsante “ARRESTO MOTORE” sopra
il flessibile del radiatore.
DAgganciare al telaio il conduttore del
pulsante “ARRESTO MOTORE”. Serra-
re il morsetto in modo che il conduttore
del pulsante “ARRESTO MOTORE”
non venga trascinato quando il manubrio
ruota a sinistra e a destra.
EAgganciare al telaio il cavo acceleratore,
il cavo della frizione e il cablaggio elet-
trico.
FAgganciare al telaio il cavo acceleratore
e il cablaggio elettrico.
GPassare il cavo della frizione davanti al
centro del dado di serraggio della testata.
HFar passare il flessibile di sfiato aria, il
flessibile di troppopieno carburante e il
tubo di sfiato del carter tra il telaio e la
biella.
ICollocare le estremità del morsetto entro
la gamma indicata dalle frecce.
JPassare il cavo acceleratore dietro il fles-
sibile di sfiato aria.
KPassare il flessibile di sfiato aria, il fles-
sibile di troppopieno carburante e il fles-
sibile di sfiato del carter in modo tale da
non farli entrare in contatto con
l’ammortizzatore posteriore.
LFissare i tubi di sfiato.
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2-15
CABLE ROUTING DIAGRAMSPEC
1Ignition coil lead
2Clamp
3CDI magneto lead
4Neutral switch lead (except for
USA and CDN)
5Radiator breather hose
6Connector cover
AClamp the ignition coil lead to
the frame at its locating tape.
Clamp it in front of the radiator
fitting boss.BClamp the CDI magneto lead to
the frame at its locating tape.
Clamp it at the rear of the radia-
tor fitting boss.
CDo not allow the neutral switch
lead to slacken except over the
radiator hose. (except for USA
and CDN)
DPass the neutral switch lead
through the holder. (except for
USA and CDN)
EPass the radiator breather hose
outside the engine bracket and
inside the down tube. Then
pass the radiator breather hose
inside the CDI magneto lead.
FClamp the CDI magneto lead,
radiator breather hose, YPVS
breather hose and neutral
switch lead (except for USA andCDN) to the frame.
GClamp the radiator breather
hose, CDI magneto lead and
neutral switch lead (except for
USA and CDN) to the frame.
HPass the CDI magneto lead,
radiator breather hose and neu-
tral switch lead (except for USA
and CDN) in front of the radiator
hose. Then pass the radiator
breather hose inside the CDI
magneto lead.
IPass the radiator breather hose
and ignition coil lead between
the frame and the radiator (left).
JLocate the clamp ends in the
arrowed range.
KBring the connector cover into
contact with the coupler.
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2-16
CABLE ROUTING DIAGRAMSPEC
1Clamp
2Wireharness
3High tension cord
4CDI unit band
5CDI unit
6CDI unit lead
7Connector cover
8Radiator hose
9Radiator breather hose
0CDI unit stayAClamp the wireharness to the
right engine bracket.
BPass the high tension cord to
the right of the radiator hose so
that the high tension cord does
not contact the radiator hose.
CPass the CDI unit lead between
the frame and the radiator
(right) and then above the radia-
tor fitting boss.
DBring the connector cover into
contact with the coupler.
EPass the radiator breather hose
behind the radiator hose.
FInsert the CDI unit band until it
stops at the CDI unit stay.
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