2001 YAMAHA WR 250F fuel

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GEN
INFO
STARTING AND BREAK-IN
STARTING AND BREAK-IN
WARNING
Never start or run the engine in a closed
area. The exhaust fumes are poisonous;
they can cause loss of consciousness and
death in a very short time. Always operate
the machine in a well-ventilated area.
CAUTION:
lThe carburetor on this motorcycle has a
built-in accelerator pump. Therefore,
when starting the engine, do not operate
the throttle or the spark plug will foul.
lUnlike a two-stroke engine, this engine
cannot be kick started when the throttle is
open because the kick starter may kick
back. Also, if the throttle is open the air/
fuel mixture may be too lean for the
engine to start.
lNever use the decompression lever after
the engine is started. The engine may be
damaged if you use the decompression
lever while it is running.
lBefore starting the machine, perform the
checks in the pre-operation check list.
STARTING A COLD ENGINE
1. Inspect the coolant level.
2. Turn the fuel cock to “ON”.
3. Shift the transmission into neutral.
4. Fully open the cold starter knob.
5. Without pulling in the decompression
lever, slowly depress the kickstarter
crank until the compression stroke is
found. When considerable resistance of
the kickstarter crank is felt, the engine is
on the compression stroke. If the engine
is on the exhaust stroke, resistance will
only be felt when the kickstarter crank is
initially depressed, not through the entire
range of depression (as when the engine
is on the compression stroke); therefore,
depress the kickstarter crank a few more
times.

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GEN
INFO
STARTING AND BREAK-IN
6. Pull the decompression lever to the han-
dlebar and depress the kickstarter crank
10 ~ 20˚.
7. Release the decompression lever and
return the kickstarter crank to its original
position and then kick the kickstarter
crank.
WARNING
Do not open the throttle while kicking the
kickstarter crank. Otherwise, the kick
starter may kick back.
8. Return the cold starter knob to its original
position and run the engine at 3,000 ~
5,000 r/min for 1 or 2 minutes.
NOTE:
Since this model is equipped with an accelera-
tor pump, if the engine is raced (the throttle
opened and closed), the air/fuel mixture will be
too rich and the engine may stall. Also unlike a
two-stroke engine, this model can idle.
CAUTION:
Do not warm up the engine for extended
periods of time.

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GEN
INFO
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, restart the engine and check its
operation within no more than 5 minutes
after it is restarted.
4. Operate the machine in the lower gears
at moderate throttle openings for five to
eight minutes.
5. Check how the engine runs when the
motorcycle is ridden with the throttle 1/4
to 1/2 open (low to medium speed) for
about one hour.
6. Restart the engine and check the opera-
tion of the machine throughout its entire
operating range. Restart the machine
and operate it for about 10 to 15 more
minutes. The machine will now be ready
to race.
CAUTION:
lAfter the break-in or before each race,
you must check the entire machine for
loose fittings and fasteners as per
“TORQUE-CHECK POINTS”.
Tighten all such fasteners as required.
lWhen any of the following parts have
been replaced, they must be broken in.
CYLINDER AND CRANKSHAFT:
About one hour of break-in operation is
necessary.
PISTON, RING, VALVES, CAMSHAFTS
AND GEARS:
These parts require about 30 minutes of
break-in operation at half-throttle or less.
Observe the condition of the engine care-
fully during operation.
STARTING AND BREAK-IN

GEN
INFO
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TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Frame construction
Combined seat and fuel tank
Exhaust system
Engine mounting
Steering Steering stem to
handlebar
Suspension Front Steering stem to front
fork
Rear For link type
Rear Installation of rear
shock absorber
Rear Installation of swing-
arm
Wheel Installation of wheel Front
Rear
Brake Front
Rear
Fuel systemFrame to rear frame
Fuel tank to frame
Silencer to rear frame
Frame to engine
Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Front fork to upper bracket
Front fork to lower bracket
Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Rear shock absorber to frame
Tightening of pivot shaft
Tightening of wheel axle
Tightening of axle holder
Tightening of wheel axle
Wheel to rear wheel sprocket
Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Fuel tank to fuel cock
NOTE:
Concerning the tightening torque, refer to
“MAINTENANCE SPECIFICATIONS” section
in the CHAPTER 2.

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GEN
INFO
CLEANING AND STORAGE
EC1B2001
STORAGE
If your machine is to be stored for 60 days or
more, some preventive measures must be
taken to avoid deterioration. 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 table-
spoon of SAE 10W-30 motor oil in the
spark plug hole, and reinstall the plug.
With the engine stop switch pushed in,
kick the engine over several times to coat
the cylinder walls with oil.
3. Remove the drive chain, clean it thor-
oughly with solvent, and lubricate 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
cover.
NOTE:
Make any necessary repairs before the
machine is stored.

SPEC

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GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: WR250FN (USA)
WR250F (EUROPE)
WR250F(N) (CDN, AUS, NZ, ZA)
Model code number: 5PH1 (USA)
5PH2 (EUROPE)
5PH4 (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 998 mm (39.3 in)
Wheelbase 1,475 mm (58.1 in)
Minimum ground clearance 382 mm (15.0 in)
Basic weight:
With oil and full fuel tank 110.0 kg (242.5 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

Yamalube 4 (20W-40) or SAE 20W-40 type
SH motor oil
(Non-Friction modified)
At 15 ˚C (60 ˚F) or lower
õ

Yamalube 4 (10W-30) or SAE 10W-30 type
SH motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
(Except for USA and CDN)
API “SH” 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

2

SPEC

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GENERAL SPECIFICATIONS
Oil capacity:
Engine oil
Periodic oil change 1.5 L (1.32 Imp qt, 1.59 US qt)
With oil filter replacement 1.6 L (1.41 Imp qt, 1.69 US qt)
Total amount 1.7 L (1.50 Imp qt, 1.80 US qt)
Coolant capacity (including all routes): 1.3 L (1.14 Imp qt, 1.37 US qt)
Air filter: Wet type element
Fuel:
Type Premium unleaded fuel with a research octane
number of 95 or higher. (Except for AUS)
Unleaded fuel only (For AUS)
Tank capacity 12 L (2.64 Imp gal, 3.17 US gal)
(For USA, CDN)
8.0 L (1.76 Imp gal, 2.11 US gal)
(Except for USA, CDN)
Reserve 1.6 L (0.35 Imp gal, 0.42 US gal)
(For USA, CDN)
1.4 L (0.31 Imp gal, 0.37 US gal)
(Except for USA, CDN)
Carburetor:
Type FCR-MX37
Manufacturer KEIHIN
Spark plug:
Type/manufacturer CR8E/NGK
U24ESR-N/DENSO
Gap 0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
Clutch type: Wet, multiple-disc
Transmission:
Primary reduction system Gear
Primary reduction ratio 57/17 (3.353)
Secondary reduction system Chain drive
Secondary reduction ratio 52/13 (4.000)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 31/13 (2.385)
2nd 28/16 (1.750)
3rd 28/21 (1.333)
4th 25/24 (1.042)
5th 22/27 (0.815)
Chassis:
Frame type Semi double cradle
Caster angle 27.1˚
Trail 117.4 mm (4.62 in)

2

SPEC
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MAINTENANCE SPECIFICATIONS
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Rear brake disc M6 ´ 1.0 6 14 1.4 10
Brake pedal M8 ´ 1.25 1 26 2.6 19
Rear brake master cylinder M6 ´ 1.0 2 10 1.0 7.2
Rear brake reservoir tank M6 ´ 1.0 1 10 1.0 7.2
Rear brake reservoir tank cap M4 ´ 0.7 2 2 0.2 1.4
Rear brake hose union bolt M10 ´ 1.25 2 30 3.0 2.2
Rear wheel axle and axle nut M20 ´ 1.5 1 125 12.5 90
Nipple (spoke) — 72 3 0.3 2.2
Rear wheel sprocket M8 ´ 1.25 6 42 4.2 30
Rear brake disc cover M6 ´ 1.0 2 7 0.7 5.1
Rear brake caliper protector M6 ´ 1.0 2 7 0.7 5.1
Engine mounting:
Engine and engine bracket (front) M10 ´ 1.25 1 69 6.9 50
Engine and frame (lower) M10 ´ 1.25 1 69 6.9 50
Engine bracket and frame M8 ´ 1.25 6 34 3.4 24
Engine and engine bracket (upper) M10 ´ 1.25 1 55 5.5 40
Lower engine guard M6 ´ 1.0 3 10 1.0 7.2
Left engine guard M8 ´ 1.25 2 23 2.3 17
Right engine guard M8 ´ 1.25 2 10 1.0 7.2
Pivot shaft and nut M16 ´ 1.5 1 85 8.5 61
Relay arm and swingarm M14 ´ 1.5 1 80 8.0 58
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 M8 ´ 1.25 3 29 2.9 21
Swingarm and brake hose holder M5 ´ — 4 4 0.4 2.9
Drive chain tensioner M8 ´ 1.25 2 19 1.9 13
Drive chain case 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 10 1.0 7.2
Fuel cock M6 ´ 1.0 2 7 0.7 5.1
Seat set bracket and fuel tank M6 ´ 1.0 1 7 0.7 5.1
Hooking screw (fitting band) and fuel tank M6 ´ 1.0 1 7 0.7 5.1
Radiator cover M6 ´ 1.0 6 4 0.4 2.9
Front fender M6 ´ 1.0 4 7 0.7 5.1
Rear fender M6 ´ 1.0 4 7 0.7 5.1
Side cover M6 ´ 1.0 2 7 0.7 5.1
Seat M8 ´ 1.25 2 23 2.3 17