engine YAMAHA WR 250F 2009 User Guide

1-15
STARTING AND BREAK-IN
Restarting an engine after a fall
Pull the hot starter lever and start the
engine. As soon as the engine starts,
Release the hot starter lever to close
the air passage.
The engine fails to start
Pull the hot starter lever all the way
out and while holding the lever, kick
the kickstarter crank 10 to 20 times to
clear the engine. Then, restart the en-
gine. Refer to "Restarting an engine
after a fall".
Observe the following break-in
procedures during initial operation
to ensure optimum performance
and avoid engine damage.
BREAK-IN PROCEDURES
1. Before starting the engine, fill the fuel tank with the fuel.
2. Perform the pre-operation checks
on the machine.
3. Start and warm up the engine. Check the idle speed, and check
the operation of the controls and
the engine stop switch. Then, re-
start the engine and check its op-
eration within no more than 5
minutes after it is restarted.
4. Operate the machine in the lower
gears at moderate throttle open-
ings for five to eight minutes.
5. Check how the engine runs when
the machine is ridden with the
throttle 1/4 to 1/2 open (low to me-
dium speed) for about one hour.
6. Restart the engine and check the operation of the machine through-
out its entire operating range. Re-
start the machine and operate it
for about 10 to 15 more minutes.
After the break-in or before each
ride, you must check the entire ma-
chine for loose fittings and fasten-
ers as per "TORQUE-CHECK
POINTS". Tighten all such fasten-
ers as required.
Thro
ttle
grip op-
era-
tion* Cold
start- er
knob Hot
start-
er le- ver
St
ar
ti
n
g
a
c
ol
d
e
n
gi
n
e Air tempera-
ture = less
than 5 °C (41
°F)
Ope
n 3
or 4
time s ON OFF
Air tempera-
ture = more
than 5 °C (41
°F) Non
e ON OFF
Air tempera-
ture (normal
temperature)
= between 5
°C (41 °F)
and 25 °C
(77 °F) Non
e ON/
OFF OFF
Air tempera-
ture = more
than 25 °C
(77 °F) Non
e OFF OFF
Starting an en-
gine after a long
period of time Non
e ON OFF
Restarting a
warm engine Non
e OFF ON
Restarting an en-
gine after a fall Non
e OFF ON
* Operate the throttle grip before kick
starting.

1-16
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Concerning the tightening torque, refer to "TIGHTENING TORQUES" section in the CHAPTER 2.
Frame constructionFrame to rear frame
Combined seat and fuel tank Fuel tank to frame
Exhaust system Silencer to rear frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front fork Front fork to upper bracket
Front fork to lower bracket
Rear For link type Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Installation of rear shock absorber Rear shock absorber to frame
Installation of swingarm Tightening of pivot shaft
Wheel Installation of wheel Front Tightening of wheel axle
Tightening of axle holder
Rear Tightening of wheel axle Wheel to rear wheel sprocket
Brake Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Rear Brake pedal to frame Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel system Fuel tank to fuel cock
Lubrication system Tightening of oil hose clamp

1-17
CLEANING AND STORAGE
CLEANING AND STORAGE
CLEANING
Frequent cleaning of your machine
will enhance its appearance, maintain
good overall performance, and ex-
tend the life of many components.
1. Before washing the machine, block off the end of the exhaust
pipe to prevent water from enter-
ing. A plastic bag secured with a
rubber band may be used for this
purpose.
2. If the engine is excessively greasy, apply some degreaser to
it with a paint brush. Do not apply
degreaser to the chain, sprockets,
or wheel axles.
3. Rinse the dirt and degreaser off with a garden hose; use only
enough pressure to do the job.
Excessive hose pressure may
cause water seepage and contami-
nation of wheel bearings, front
forks, brakes and transmission
seals. Many expensive repair bills
have resulted from improper high
pressure detergent applications
such as those available in coin-op-
erated car washers.
4. After the majority of the dirt has been hosed off, wash all surfaces
with warm water and a mild deter-
gent. Use an old toothbrush to
clean hard-to-reach places.
5. Rinse the machine off immediate- ly with clean water, and dry all
surfaces with a soft towel or cloth.
6. Immediately after washing, re- move excess water from the
chain with a paper towel and lubri-
cate the chain to prevent rust.
7. Clean the seat with a vinyl uphol- stery cleaner to keep the cover
pliable and glossy.
8. Automotive wax may be applied to all painted or chromed surfac-
es. Avoid combination cleaner-
waxes, as they may contain abra-
sives.
9. After completing the above, start the engine and allow it to idle for
several minutes. STORAGE
If your machine is to be stored for 60
days or more, some preventive mea-
sures must be taken to avoid deterio-
ration. After cleaning the machine
thoroughly, prepare it for storage as
follows:
1. Drain the fuel tank, fuel lines, and
the carburetor float bowl.
2. Remove the spark plug, pour a ta-
blespoon of SAE 10W-30 motor
oil in the spark plug hole, and re-
install the plug. With the engine
stop switch pushed in, kick the en-
gine over several times to coat the
cylinder walls with oil.
3. Remove the drive chain, clean it thoroughly with solvent, and lubri-
cate it. Reinstall the chain or store
it in a plastic bag tied to the frame.
4. Lubricate all control cables.
5. Block the frame up to raise the wheels off the ground.
6. Tie a plastic bag over the exhaust pipe outlet to prevent moisture
from entering.
7. If the machine is to be stored in a humid or salt-air environment,
coat all exposed metal surfaces
with a film of light oil. Do not apply
oil to rubber parts or the seat cov-
er.
Make any necessary repairs before
the machine is stored.

2-1
GENERAL SPECIFICATIONS
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model name:WR250FY (USA, CDN, AUS, NZ)
WR250F (EUROPE, ZA)
Model code number: 5UMN (USA)
5UMP (CDN)
5UMR (EUROPE)
5UMS (AUS, NZ, ZA)
Dimensions: USA, CDN, ZA AUS, NZ EUROPE
Overall length 2,165 mm (85.24
in) 2,180 mm (85.83
in) 2,190 mm (86.22
in)
Overall width 825 mm (32.48 in)←←
Overall height 1,300 mm (51.18
in) 1,305 mm (51.38
in) ←
Seat height 980 mm (38.58 in) 990 mm (38.98 in)←
Wheelbase 1,480 mm (58.27
in) ←
1,485 mm (58.46
in)
Minimum ground clearance 365 mm (14.37 in) 370 mm (14.57 in) 375 mm (14.76 in)
Dry weight: Without oil and fuel 106.0 kg (233.7 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 Kick and electric starter
Lubrication system: Dry sump
Oil type or grade: Engine oil (For USA and CDN)
Yamalube 4, SAE10W-40 or SAE20W-50
Yamalube 4-R, SAE10W-50
API service SG type or higher,
JASO standard MA
(Except for USA and CDN)
SAE10W-30, SAE10W-40, SAE15W-40,
SAE20W-40 or SAE20W-50
API service SG type or higher,
JASO standard MA

2-2
GENERAL SPECIFICATIONS
Oil capacity:Engine oilPeriodic oil change 1.1 L (0.97 Imp qt, 1.16 US qt)
With oil filter replacement 1.2 L (1.06 Imp qt, 1.27 US qt)
Total amount 1.4 L (1.23 Imp qt, 1.48 US qt)
Coolant capacity (including all routes): 0.99 L (0.87 Imp qt, 1.05 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)
Reserve 1.1 L (0.24 Imp gal, 0.29 US gal)
Carburetor: Type FCR-MX37
Manufacturer KEIHIN
Spark plug: Type/manufacturer CR9E/NGK (resistance type)
Gap 0.7–0.8 mm (0.028–0.031 in)
Clutch type: Wet, multiple-disc
Transmission: USA, CDN, ZA, AUS, NZEUROPE
Primary reduction system Gear←
Primary reduction ratio 57/17 (3.353)←
Secondary reduction system Chain drive←
Secondary reduction ratio 50/13 (3.846)47/14 (3.357)
Transmission type Constant mesh, 5-speed←
Operation Left foot operation←
Gear ratio: 1st 31/13 (2.385)←
2nd 28/16 (1.750)←
3rd 23/17 (1.353)←
4th 23/21 (1.095)←
5th 17/19 (0.895)←
Chassis: USA, CDN, ZA AUS, NZ EUROPE
Frame type Semi double cra-
dle ←←
Caster angle 27.0 °26.6 ° 26.5 °
Trail 115 mm (4.53 in) 114 mm (4.49 in) 113 mm (4.45 in)
Tire: Type With tube
Size (front) 80/100-21 51M (For USA, CDN and ZA)
90/90-21 54R (For EUROPE, AUS and NZ)
Size (rear) 100/100-18 59M (For USA, CDN and ZA)
130/90-18 69R (For EUROPE, AUS and NZ)
Tire pressure (front and rear) 100 kPa (1.0 kgf/cm
2, 15 psi)
2

2-3
MAINTENANCE SPECIFICATIONS
MAINTENANCE SPECIFICATIONS
ENGINEBrake:
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 310 mm (12.2 in)
Electrical: Ignition system CDI
Generator system AC magneto
Battery type YTZ7S (F)
Battery voltage/capacity 12V/6 AH
Specific gravity 1.310
Headlight type: Quartz bulb (halogen)
Bulb wattage × quantity: Headlight 12 V 35/36.5 W × 1
Taillight 12 V 1.6/0.3 W × 1
ItemStandardLimit
Cylinder head: Warp limit ----0.05 mm (0.002
in)
Cylinder: Bore size 77.00–77.01 mm (3.0315–3.0319 in) ----
Out of round limit ----0.05 mm (0.002
in)
Camshaft: Drive method Chain drive (Left)----
Camshaft cap inside diameter 22.000–22.021 mm (0.8661–0.8670 in) ----
Camshaft outside diameter 21.959–21.972 mm (0.8645–0.8650 in) ----
Shaft-to-cap clearance 0.028–0.062 mm (0.0011–0.0024 in) 0.08 mm (0.003
in)

2-8
MAINTENANCE SPECIFICATIONS
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: USA, CDN, ZA,
AUS, NZ EUROPE
Type/manufacturer FCR-MX37/KEIHIN← ----
I. D. mark 5UME E05UML L0 ----
Main jet (M.J) #170#160 ----
Main air jet (M.A.J) #115← ----
Jet needle (J.N) NJRUNNGU ----
Cutaway (C.A) 1.5← ----
Pilot jet (P.J) #42#45 ----
Pilot air jet (P.A.J) #70← ----
Pilot outlet (P.O) ø0.9← ----
Bypass (B.P) ø1.0← ----
Valve seat size (V.S) ø3.8← ----
Starter jet (G.S) #68← ----
Leak jet (Acc.P) #70← ----
Float height (F.H) 8 mm (0.31 in)← ----
Engine idle speed 1,750–1,950 r/min← ----
Intake vacuum 31.3–36.7 kPa
(235–275 mmHg,
9.25–10.83 inHg)←
----
Hot starter lever free play 3–6 mm (0.12–0.24
in) ←
----
Lubrication system: Oil filter type Paper type----
Oil pump type Trochoid type----
Tip clearance 0.12 mm or less (0.0047 in or less) 0.20 mm (0.008
in)
Side clearance 0.09–0.17 mm (0.0035–0.0067 in) 0.24 mm (0.009
in)
Housing and rotor clearance 0.03–0.10 mm (0.0012–0.0039 in) 0.17 mm
(0.0067 in)
Cooling: Radiator core sizeWidth 120.2 mm (4.73 in)----
Height 240 mm (9.45 in)----
Thickness 22 mm (0.87 in)----
Radiator cap opening pressure 110 kPa (1.1 kg/cm
2, 15.6 psi)----
Radiator capacity (total) 0.54 L (0.48 Imp qt, 0.57 US qt)----
Water pump Type Single-suction centrifugal pump----
Item
StandardLimit

2-12
TIGHTENING TORQUES
TIGHTENING TORQUES
ENGINE
△- marked portion shall be checked for torque tightening after break-in or before each race.
Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb
Spark plug M10S × 1.0 1 13 1.3 9.4
Camshaft cap M6 × 1.0 10 10 1.0 7.2
Cylinder head blind plug screw M12 × 1.0 1 28 2.8 20
Cylinder head (stud bolt) M6 × 1.0 2 7 0.7 5.1
Cylinder head (stud bolt) M8 × 1.25 1 15 1.5 11
Cylinder head (bolt) M9 × 1.25 4 38 3.8 27
Cylinder head (nut) M6 × 1.0 2 10 1.0 7.2
Cylinder head cover M6 × 1.0 2 10 1.0 7.2
Cylinder M6 × 1.0 1 10 1.0 7.2
Balancer weight M6 × 1.0 2 10 1.0 7.2
Balancer shaft driven gear M14 × 1.0 1 50 5.0 36
Timing chain guide (intake side) M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner cap bolt M6 × 1.0 1 7 0.7 5.1
Impeller M8 × 1.25 1 14 1.4 10
Radiator hose clamp M6 × 1.0 10 2 0.2 1.4
Coolant drain bolt M6 × 1.0 1 10 1.0 7.2
Water pump housing M6 × 1.0 4 10 1.0 7.2
Radiator stay M6 × 1.0 6 10 1.0 7.2
Radiator M6 × 1.0 4 10 1.0 7.2
Radiator pipe M6 × 1.0 1 10 1.0 7.2
Oil pump cover M4 × 0.7 1 1.7 0.17 1.2
Oil pump M6 × 1.0 3 10 1.0 7.2
Oil filter element drain bolt M6 × 1.0 1 10 1.0 7.2
Oil filter element cover M6 × 1.0 2 10 1.0 7.2
Oil strainer (crankcase) M6 × 1.0 2 10 1.0 7.2
Oil delivery pipe 1 (M10) M10 × 1.25 1 20 2.0 14
Oil delivery pipe 1 (M8) M8 × 1.25 2 18 1.8 13
Oil hose M6 × 1.0 2 8 0.8 5.8
△ Oil hose clamp —2 2 0.2 1.4
Oil strainer (oil tank) M6 × 1.0 1 9 0.9 6.5
Oil tank drain bolt M8 × 1.25 1 18 1.8 13
Oil tank (upper) M6 × 1.0 1 7 0.7 5.1
Oil tank and frame M6 × 1.0 3 9 0.9 6.5
Oil pressure check bolt M6 × 1.0 1 10 1.0 7.2
Carburetor joint M6 × 1.0 2 10 1.0 7.2
Carburetor joint clamp M4 × 0.7 2 3 0.3 2.2
Air filter joint clamp M6 × 1.0 1 3 0.3 2.2

2-15
TIGHTENING TORQUES
△Rear wheel sprocket M8 × 1.25 6 50 5.0 36
△ Rear brake disc cover M6 × 1.0 2 10 1.0 7.2
△ Rear brake caliper protector M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 19 1.9 13
Engine mounting:
△ Engine and engine bracket (front) M10 × 1.25 1 53 5.3 38
△ Engine and frame (lower) M10 × 1.25 1 53 5.3 38
△ Upper engine bracket and frame M8 × 1.25 4 34 3.4 24
△ Lower engine bracket and frame M8 × 1.25 4 34 3.4 24
△ Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
△ Engine guard M6 × 1.0 3 7 0.7 5.1
Regulator M6 × 1.0 2 7 0.7 5.1
△ Pivot shaft and nut M16 × 1.5 1 85 8.5 61
△ Relay arm and swingarm M14 × 1.5 1 70 7.0 50
△ Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
△ Connecting rod and frame M14 × 1.5 1 80 8.0 58
△ Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
△ Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
△ Rear frame (upper) M8 × 1.25 1 38 3.8 27
△ Rear frame (lower) M8 × 1.25 2 32 3.2 23
△ Swingarm and brake hose holder M5 × 0.8 4 3 0.3 2.2
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Upper drive chain tensioner M8 × 1.25 1 16 1.6 11
Lower drive chain tensioner M8 × 1.25 1 16 1.6 11
Drive chain support M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
△ Fuel tank M6 × 1.0 2 9 0.9 6.5
△ Fuel cock M6 × 1.0 2 4 0.4 2.9
Seat set bracket and fuel tank M6 × 1.0 1 7 0.7 5.1
Fuel tank bracket and fuel tank M6 × 1.0 4 7 0.7 5.1
△ Air scoop and fuel tank M6 × 1.0 6 7 0.7 5.1
△ Air scoop and radiator guard (lower) M6 × 1.0 2 6 0.6 4.3
△ Front fender M6 × 1.0 4 7 0.7 5.1
△ Rear fender (front) M6 × 1.0 2 7 0.7 5.1
△ Rear fender (rear) M6 × 1.0 2 11 1.1 8.0
△ Side cover M6 × 1.0 2 7 0.7 5.1
△ Seat M8 × 1.25 2 23 2.3 17
Multi-function display bracket and upper bracket M6 × 1.0 2 7 0.7 5.1
Multi-function display M5 × 0.8 2 4 0.4 2.9
Plate 1 and front fork protector M5 × 0.8 2 4 0.4 2.9
Plate 2 and front fork protector — 2 0.5 0.05 0.36
Speed sensor lead holder and lower bracket M6 × 1.0 1 13 1.3 9.4
Speed sensor lead holder and clamp M6 × 1.0 1 7 0.7 5.1 Part to be tightened Thread size Q'ty
Tightening torque
Nm m•kg ft•lb

2-17
TIGHTENING TORQUES
GENERAL TORQUE
SPECIFICATIONS
This chart specifies torque for stan-
dard fasteners 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-fastener as-
semblies in a crisscross fashion, in
progressive stages, until full torque is
reached. Unless otherwise specified,
torque specifications call for clean,
dry threads. Components should be
at room temperature.A. Distance between flats
B. Outside thread diameter
DEFINITION OF UNITS
A
(Nut) B
(Bolt
) TORQUE SPECIFI-
CATION
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
millimeter 10-3 meterLength
cmcentimeter 10-2 meterLength
kgkilogram 103 gramWeight
NNewton 1 kg × m/sec2Force
NmNewton meterN × mTorque
m•kgMeter kilogram m × kgTorque
PaPascal N/m2Pressure
N/mmNewton per millimeter N/mm Spring rate
LLiter—Volume or capacity
cm3Cubic centimeter —Volume or capacity
r/minRevolution per minute —Engine speed