6. GASOLINE CAN CAUSE INJURY.
If you should swallow some gasoline,
inhale excess gasoline vapors, or
allow any gasoline to get into your
eyes, contact a doctor immediately. If
any gasoline spills onto your skin or
clothing, immediately wash skin areas
with soap and water, and change your
clothes.
7. ONLY OPERATE THE MACHINE IN AN
AREA WITH ADEQUATE VENTILA-
TION.
Never start the engine or let it run for
any length of time in an enclosed area.
Exhaust fumes are poisonous. These
fumes contain carbon monoxide,
which by itself is odorless and color-
less. Carbon monoxide is a dangerous
gas which can cause unconscious-
ness or can be lethal.
8. PARK THE MACHINE CAREFULLY;
TURN OFF THE ENGINE.
Always turn off the engine if you are
going to leave the machine. Do not
park the machine on a slope or soft
ground as it may fall over.
9. THE ENGINE, EXHAUST PIPE, MUF-
FLER, AND OIL TANK WILL BE VERY
HOT AFTER THE ENGINE HAS BEEN
RUN.
Be careful not to touch them or to
allow any clothing item to contact
them during inspection or repair.
10. PROPERLY SECURE THE MACHINE
BEFORE TRANSPORTING IT.
When transporting the machine in
another vehicle, always be sure it is
properly secured and in an upright
position and that the fuel cock is in
the “OFF” position. Otherwise, fuel
may leak out of the carburetor or fuel
tank.
SPEC
2 - 1
GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: YZ250FS (USA)
YZ250F (EUROPE)
YZ250F(S) (CDN, AUS, NZ, ZA)
Model code number: 5XC1 (USA)
5XC2 (EUROPE)
5XC4 (CDN, AUS, NZ, ZA)
Dimensions:
Overall length 2,165 mm (85.2 in)
Overall width 827 mm (32.6 in)
Overall height 1,303 mm (51.3 in)
Seat height 995 mm (39.2 in)
Wheelbase 1,475 mm (58.1 in)
Minimum ground clearance 382 mm (15.0 in)
Dry weight:
Without oil and fuel 93.5 kg (206 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder, forward inclined
Displacement 249 cm
3
(8.76 Imp oz, 8.42 US oz)
Bore
×
stroke 77.0
×
53.6 mm (3.03
×
2.11 in)
Compression ratio 12.5 : 1
Starting system Kickstarter
Lubrication system: Dry sump
Oil type or grade:
Engine oil (For USA and CDN)
At 5 ˚C (40 ˚F) or higher
Å
Yamalube 4 (20W-40) or SAE 20W-40 type
SG motor oil
(Non-Friction modified)
At 15 ˚C (60 ˚F) or lower
ı
Yamalube 4 (10W-30) or SAE 10W-30 type
SG motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
(Except for USA and CDN)
API “SG” or higher grade
-20
-4-10
140
3010
5020
6830
8640 50
104
122°CTemp.
°F
10W-30
10W-40
20W-40
20W-50
15W-40
2
SPEC
2 - 6
MAINTENANCE SPECIFICATIONS
Stem runout limit ---- 0.01 mm
(0.0004 in)
Valve seat width IN 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
EX 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
Valve spring:
Free length IN 37.81 mm (1.49 in) 36.81 mm
(1.45 in)
EX 37.54 mm (1.48 in) 36.54 mm
(1.44 in)
Set length (valve closed) IN 29.13 mm (1.15 in) ----
EX 29.30 mm (1.15 in) ----
Compressed force
(installed) IN 99 ~ 114 N at 29.13 mm
(9.9 ~ 11.4 kg at 29.13 mm,
22.27 ~ 25.57 lb at 1.15 in)----
EX 126 ~ 144 N at 29.30 mm
(12.6 ~ 14.4 kg at 29.30 mm,
28.44 ~ 32.41 lb at 1.15 in)----
Tilt limit IN ---- 2.5˚/ 1.7 mm
(2.5˚/0.067 in)
EX ---- 2.5˚/1.6 mm
(2.5˚/0.063 in)
Direction of winding
(top view) IN Clockwise ----
EX Clockwise ----
Piston:
Piston to cylinder clearance 0.040 ~ 0.065 mm
(0.0016 ~ 0.0026 in)0.1 mm
(0.004 in)
Piston size “D”76.955 ~ 76.970 mm
(3.0297 ~ 3.0303 in)----
Measuring point “H”8 mm (0.31 in) ----
Piston off-set 0.5 mm (0.020 in)/IN-side ----Item Standard Limit
*
H
D
SPEC
2 - 8
MAINTENANCE SPECIFICATIONS
Clutch:
Friction plate thickness 2.9 ~ 3.1 mm
(0.114 ~ 0.122 in)2.7 mm
(0.106 in)
Quantity 9 ----
Clutch plate thickness 1.1 ~ 1.3 mm (0.043 ~ 0.051 in) ----
Quantity 8 ----
Warp limit ---- 0.1 mm
(0.004 in)
Clutch spring free length 40.4 mm (1.59 in) 39.4 mm
(1.55 in)
Quantity 5 ----
Clutch housing thrust clearance 0.10 ~ 0.35 mm
(0.0039 ~ 0.0138 in)----
Clutch housing radial clearance 0.010 ~ 0.044 mm
(0.0004 ~ 0.0017 in)----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm
(0.002 in)
Kickstarter:
Type Kick and ratchet type ----
Carburetor:
Type/manufacturer FCR-MX37/KEIHIN ----
I. D. mark 5XC1 00 ----
Main jet (M.J) #180 ----
Main air jet (M.A.J)ø2.0 ----
Jet needle (J.N) OBEKR-4 ----
Cutaway (C.A) 1.5 ----
Pilot jet (P.J) #42 ----
Pilot air jet (P.A.J) #100 ----
Pilot outlet (P.O)ø0.9 ----
Pilot screw (example) (P.S) 1-5/8 ----
Bypass (B.P)ø1.0 ----
Valve seat size (V.S)ø3.8 ----
Starter jet (G.S) #72 ----
Leak jet (Acc.P) #90 ----
Float height (F.H) 8 mm (0.31 in) ----
Engine idle speed 1,900 ~ 2,100 r/min ----
Intake vacuum26.7 ~ 32.0 kPa
(200 ~ 240 mmHg, 7.87 ~ 9.45 inHg)----
Hot starter lever free play 3 ~ 6 mm (0.12 ~ 0.24 in) ----Item Standard Limit
SPEC
2 - 12
MAINTENANCE SPECIFICATIONS
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension:
Front fork travel 300 mm (11.8 in) ----
Fork spring free length 479 mm (18.9 in) 474 mm (18.7 in)
Spring rate, STD K = 4.2 N/mm
(0.428 kg/mm, 24.0 lb/in)----
Optional spring/spacer Yes ----
Oil capacity 662 cm
3 (23.3 Imp oz, 22.4 US oz) ----
Oil level 125 mm (4.92 in) ----
(From top of outer tube with inner
tube and damper rod fully com-
pressed without spring.)105 ~ 135 mm (4.13 ~ 5.31 in) ----
Oil grade Suspension oil “01”----
Inner tube outer diameter 48 mm (1.89 in) ----
Front fork top end 5 mm (0.20 in) ----
Rear suspension: USA, CDN,
AUS, NZ, ZAEUROPE
Shock absorber travel 132 mm (5.20 in)←----
Spring free length 260 mm
(10.24 in)275 mm
(10.83 in)----
Fitting length 249 mm
(9.80 in)264.5 mm
(10.41 in)----
(9.47 ~ 10.18 in)255.5~ 273.5 mm
(10.06 ~ 10.77 in)----
Spring rate, STD K = 46.0 N/mm
(4.70 kg/mm,
263.2 lb/in)K = Approx.
48.0 N/mm
(4.90 kg/mm,
274.4 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)
SPEC
2 - 13
MAINTENANCE SPECIFICATIONS
Wheel:
Front wheel type Spoke wheel ----
Rear wheel type Spoke wheel ----
Front rim size/material 21 × 1.60/Aluminum ----
Rear rim size/material 19 × 1.85/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 111 links + joint ----
Chain slack 40 ~ 50 mm (1.6 ~ 2.0 in) ----
Chain length (10 links) ----152.5 mm (6.00 in)
Front disc brake:
Disc outside dia. × Thickness 250 × 3.0 mm (9.84 × 0.12 in) 250 × 2.5 mm
(9.84 × 0.10 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 245 × 4.0 mm (9.65 × 0.16 in) 245 × 3.5 mm
(9.65 × 0.14 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. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 25.4 mm (1.000 in) × 1 ----
Brake fluid type DOT #4 ----
Brake lever and brake pedal:
Brake lever position 95 mm (3.74 in) ----
Brake pedal height
(vertical height above footrest top)5 mm (0.20 in) ----
Clutch lever free play (lever end) 8 ~ 13 mm (0.31 ~ 0.51 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit
SPEC
2 - 17
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm m•kg ft•lb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3 meter
10-2 meterLength
Length
kg kilogram 10
3 gram Weight
N Newton 1 kg × m/sec
2 Force
Nm
m • kgNewton meter
Meter kilogramN × m
m × kgTorque
Torque
Pa Pascal N/m
2Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3 Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute—Engine speed
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
3 - 1
INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the
required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)
As re-
quiredRemarks
ENGINE OIL
Replace
Inspect
●
●●
●
OIL FILTER ELEMENT, OIL STRAINER
Clean
●
VALVES
Check the valve clearances
Inspect
Replace
●
●
●
●
The engine must be cold.
Check the valve seats
and valve stems for wear.
VALVE SPRINGS
Inspect
Replace
●
●
Check the free length and
the tilt.
VALVE LIFTERS
Inspect
Replace
●
●
Check for scratches and
wear.
CAMSHAFTS
Inspect
Replace
●
●
Inspect the camshaft sur-
face.
Inspect the decompres-
sion system.
TIMING CHAIN SPROCKETS, TIMING
CHAIN
Inspect
Replace
●
●
Check for wear on the
teeth and for damage.
PISTON
Inspect
Clean
Replace
●
●
●
●
Inspect crack
Inspect carbon deposits
and eliminate them.
PISTON RING
Inspect
Replace
●
●
●
Check ring end gap
PISTON PIN
Inspect
Replace
●
●
CYLINDER HEAD
Inspect and clean
●
Inspect carbon deposits
and eliminate them.
Change gasket
CYLINDER
Inspect and clean
Replace
●
●
Inspect score marks
Inspect wear
CLUTCH
Inspect and adjust
Replace
●
●
●
Inspect housing, friction
plate, clutch plate and
spring
TRANSMISSION
Inspect
Replace bearing
●
●