engine oil YAMAHA WR 250F 2002 Owners Manual

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.

ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols
1
to
7
are designed as
thumb tabs to indicate the chapter’s number
and content.
1
General information
2
Specifications
3
Regular inspection and adjustments
4
Engine
5
Chassis
6
Electrical
7
Tuning
Illustrated symbols
8
to
D
are used to identify
the specifications appearing in the text.
8
With engine mounted
9
Special tool
0
Filling fluid
A
Lubricant
B
Tightening
C
Specified value, Service limit
D
Resistance (
Ω
), Voltage (V), Electric current (A)
Illustrated symbols
E
to
H
in the exploded
diagrams indicate grade of lubricant and loca-
tion of lubrication point.
E
Apply engine oil
F
Apply molybdenum disulfide oil
G
Apply lightweight lithium-soap base grease
H
Apply molybdenum disulfide grease
Illustrated symbols
I
to
J
in the exploded
diagrams indicate where to apply a locking
agent and where to install new parts.
IApply locking agent (LOCTITE®)
JUse new one 12
34
56
78
90
AB
CD
EF
GH
IJ
GEN
INFOSPEC
INSP
ADJENG
CHAS–+ELEC
TUN
T R..
EM
BM

CHAPTER 4
ENGINE
SEAT, FUEL TANK
AND SIDE COVERS
................................. 4-1
EXHAUST PIPE AND SILENCER
............ 4-2
RADIATOR
................................................ 4-4
CARBURETOR
......................................... 4-7
CAMSHAFTS
.......................................... 4-21
CYLINDER HEAD
................................... 4-30
VALVES AND VALVE SPRINGS
........... 4-34
CYLINDER AND PISTON
....................... 4-43
CLUTCH
.................................................. 4-50
OIL FILTER ELEMENT, WATER PUMP
AND RIGHT CRANKCASE COVER
...... 4-57
BALANCER
............................................ 4-64
OIL PUMP
............................................... 4-67
KICK SHAFT AND SHIFT SHAFT
.......... 4-72
CDI MAGNETO
....................................... 4-79
ENGINE REMOVAL
................................ 4-83
CRANKCASE AND CRANKSHAFT
....... 4-88
TRANSMISSION, SHIFT CAM
AND SHIFT FORK
.................................. 4-97
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL
...... 5-1
FRONT BRAKE AND REAR BRAKE
..... 5-11
FRONT FORK
......................................... 5-28
HANDLEBAR
.......................................... 5-41
STEERING
.............................................. 5-47
SWINGARM
............................................ 5-53
REAR SHOCK ABSORBER
................... 5-60

GEN
INFO

1 - 1
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1
Clutch lever
2
Decompression lever
3
Trip meter
4
Light switch
5
Front brake lever
6
Throttle grip
7
Radiator cap
8
Fuel tank cap
9
Oil tank cap
0
Engine stop switch
A
Taillight
B
Kickstarter crank
C
Fuel tank
D
Headlight
E
Radiator
F
Coolant drain bolt
G
Rear brake pedal
H
Valve joint
I
Fuel cock
J
Cold starter knob
K
Hot starter knob (red)
L
Drive chain
M
Air filter
N
Shift pedal
O
Front fork
NOTE:


The machine you have purchased may differ
slightly from those shown in the following.

Designs and specifications are subject to
change without notice.

1 - 4
GEN
INFO

IMPORTANT INFORMATION
EC132000
ALL REPLACEMENT PARTS
1. We recommend to use Yamaha genuine
parts for all replacements. Use oil and/or
grease recommended by Yamaha for
assembly and adjustment.
EC133000
GASKETS, OIL SEALS AND O-RINGS
1. All gaskets, oil seals, and O-rings should
be replaced when an engine is over-
hauled. All gasket surfaces, oil seal lips,
and O-rings must be cleaned.
2. Properly oil all mating parts and bearings
during reassembly. Apply grease to the
oil seal lips.
EC134000
LOCK WASHERS/PLATES AND COTTER
PINS
1. All lock washers/plates
1
and cotter pins
must be replaced when they are
removed. Lock tab(s) should be bent
along the bolt or nut flat(s) after the bolt
or nut has been properly tightened.
EC135001
BEARINGS AND OIL SEALS
1. Install the bearing(s)
1
and oil seal(s)
2
with their manufacturer’s marks or num-
bers facing outward. (In other words, the
stamped letters must be on the side
exposed to view.) When installing oil
seal(s), apply a light coating of light-
weight lithium base grease to the seal
lip(s). Oil the bearings liberally when
installing.
CAUTION:
Do not use compressed air to spin the
bearings dry. This causes damage to the
bearing surfaces.

GEN
INFO
1 - 8
SPECIAL TOOLS
YU-33975, 90890-01403 Steering nut wrench
This tool is used when tighten the steering ring nut to
specification.YU-33975 90890-01403
YM-1423, 90890-01423 Damper rod holder
Use this tool to remove and install the damper rod.YM-1423 90890-01423
YM-01442, 90890-01442 Fork seal driver
This tool is used when install the fork oil seal.YM-01442 90890-01442
YU-3112-C, 90890-03112 Pocket tester
Use this tool to inspect the coil resistance, output
voltage and amperage.YU-3112-C 90890-03112
YU-8036-B
90890-03113Inductive tachometer
Engine tachometer
This tool is needed for observing engine rpm.YU-8036-B 90890-03113
YM-33277-A, 90890-03141 Timing light
This tool is necessary for checking ignition timing.YM-33277-A 90890-03141
YM-4019, 90890-04019 Valve spring compressor
This tool is needed to remove and install the valve
assemblies.YM-4019 90890-04019
YM-91042, 90890-04086 Clutch holding tool
This tool is used to hold the clutch when removing or
installing the clutch boss securing nut.YM-91042 90890-04086
YM-4111, 90890-04111
YM-4116, 90890-04116Valve guide remover
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to remove and install the valve
guide.YM-4111
YM-411690890-04111
90890-04116
Part number Tool name/How to use Illustration

1 - 21
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

2 - 1
GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: WR250FP (USA)
WR250F (EUROPE)
WR250F(P) (CDN, AUS, NZ, ZA)
Model code number: 5PH5 (USA)
5PH6 (EUROPE)
5PH8 (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
Å
Yamalube 4 (20W-40) or SAE 20W-40 type
SH motor oil
(Non-Friction modified)
At 15 ˚C (60 ˚F) or lower
ı

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

SPEC

2 - 2
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 gasoline only with a
research octane number of 95 or higher.
(Except for ZA)
Premium gasoline (For ZA)
Tank capacity 12 L (2.64 Imp gal, 3.17 US gal)
(For USA and CDN)
8.0 L (1.76 Imp gal, 2.11 US gal)
(Except for USA and CDN)
Reserve 1.6 L (0.35 Imp gal, 0.42 US gal)
(For USA and CDN)
1.4 L (0.31 Imp gal, 0.37 US gal)
(Except for USA and 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

2 - 19
SPEC

CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Hose guide
2
Brake hose
3
Voltage regulator
4
Light switch lead
5
Fuel tank breather hose
6
Engine stop switch lead
7
Clamp
8
Oil tank breather hose
9
Sub-wire harness
0
Taillight lead
A
Throttle position sensor lead
B
Neutral switch lead
C
Oil hose
D
Cylinder head breather hose
E
CDI magneto lead
F
Clutch cable
G
Cable guide
H
Carburetor breather hose
I
Carburetor overflow hose
J
Coolant reservoir breather hose
K
Decompression cable
L
Ground lead
M
Ignition coil lead
N
CDI unit lead
O
Voltage regulator lead
Å
Pass the fuel tank breather hose
behind handlebar, then insert it
into the steering stem hole.
ı
Pass the decompression cable,
engine stop switch lead and light
switch lead under where the oil
hose is attached.
Ç
Pass the voltage regulator lead,
engine stop switch lead and light
switch lead over the radiator
hose.
Î
Fasten the engine stop switch
lead, light switch lead and igni-
tion coil lead of the sub-wire har-
ness.
‰
Fasten the sub-wire harness
and engine stop switch lead.
Ï
Pass the cylinder head breather
hose along the right side of the
oil tank breather hose.
Ì
Fasten the sub-wire harness
and light switch lead in front of
the upper engine brackets.
Ó
Fasten the sub-wire harness.
È
Pass the sub-wire harness
between the upper engine
brackets.
Ô
Fasten the sub-wire harness.

Fasten the throttle position sen-
sor lead.