2002 YAMAHA YZ250F maintenance

SPEC
2 - 16
MAINTENANCE SPECIFICATIONS
EC212300
ELECTRICAL
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Magneto-model (stator)/manufac-
turer5SF-00/YAMAHA ----
Charging coil 1 resistance (color) 720 ~ 1,080 Ω at 20 ˚C (68 ˚F)
(Green – Brown)----
Charging coil 2 resistance (color) 44 ~ 66 Ω at 20 ˚C (68 ˚F)
(Black – Pink)----
Pickup coil resistance (color) 248 ~ 372 Ω at 20 ˚C (68 ˚F)
(White – Red)----
CDI unit-model/manufacturer 5SG-00/YAMAHA ----
Ignition coil:
Model/manufacturer 4SR-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.20 ~ 0.30 Ω at 20 ˚C (68 ˚F) ----
Secondary coil resistance 9.5 ~ 14.3 kΩ at 20 ˚C (68 ˚F) ----
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Stator M6 × 1.0 3 10 1.0 7.2
Rotor M10 × 1.25 1 48 4.8 35
Neutral switch M5 × 0.8 2 4 0.4 2.9
Ignition coil M6 × 1.0 2 7 0.7 5.1

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.
TIMING CHAIN SPROCKETS, TIMING
CHAIN
Inspect
Replace
●

●
Check for wear on the
teeth and for damage.
PISTON
Inspect
Clean
Replace
●

●

●

●
Inspect crack
Remove carbon
PISTON RING
Inspect
Replace
●

●

●
Check ring end gap
PISTON PIN
Inspect
Replace
●

●

CYLINDER HEAD
Inspect and clean
●
Remove carbon
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
●

●

3 - 2
INSP
ADJ

MAINTENANCE INTERVALS
SHIFT FORK, SHIFT CAM, GUIDE BAR
Inspect
●
Inspect wear
ROTOR NUT
Retighten
●

●

EXHAUST PIPE, SILENCER, PRO-
TECTOR
Inspect and retighten
Clean
Replace
●

●

●

●
* Whichever comes first
CRANK
Inspect and clean
●

●

CARBURETOR
Inspect, adjust and clean
●

●
When using a high-pres-
sure washer, make sure
that water does not enter
the accelerator pump.
SPARK PLUG
Inspect and clean
Replace
●

●

●

DRIVE CHAIN
Lubricate, slack, alignment
Replace
●

●

●
Use chain lube
Chain slack: 40 ~ 50 mm
(1.6 ~ 2.0 in)
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolant
Inspect hoses
●

●

●

●

●
Every two years
OUTSIDE NUTS AND BOLTS
Retighten
●

●
Refer to “STARTING
AND BREAK-IN” section
in the CHAPTER 1.
AIR FILTER
Clean and lubricate
Replace
●

●

●
Use foam air-filter oil
FRAME
Clean and inspect
●

●

FUEL TANK, COCK
Clean and inspect
●

●

BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper
bolts, master cylinder bolts and union
bolts
Replace pads
Replace brake fluid
●

●

●

●

●

●

●

●

●

●

●

●
Every one year
FRONT FORKS
Inspect and adjust
Replace oil
Replace oil seal
●

●

●

●

●
Suspension oil “01” ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)
As re-
quiredRemarks


3

3 - 3
INSP
ADJ

MAINTENANCE INTERVALS
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube
●

●
Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
Retighten
●

●

●

●

●

(After
rain ride)
●
Molybdenum disulfide
grease
CHAIN GUARD AND ROLLERS
Inspect
●
●
SWINGARM
Inspect, lube and retighten
● ● Molybdenum disulfide
grease
RELAY ARM, CONNECTING ROD
Inspect, lube and retighten
● ● Molybdenum disulfide
grease
STEERING HEAD
Inspect free play and retighten
Clean and lube
Replace bearing
● ●
●
● Lithium base grease
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate
●
●
●
●
●
●
●
Lithium base grease
THROTTLE, CONTROL CABLE
Check routing and connection
Lubricate
Inspect and clean (throttle cable)
●
●
● ●

●
● Yamaha cable lube or
SAE 10W-30 motor oil
Inspect dirt and wear on
the throttle cable on the
carburetor side. ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks

3 - 4
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-14
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-13 ~ 17
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10 ~ 11
Brakes Check the play of front brake and effect of front and rear brake. P.3-25 ~ 31
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-32 ~ 34
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-42 ~ 43
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-43 ~ 44
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-34 ~ 41
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or
when the front forks travel up and down.—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-2
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-32
Lubrication Check for smooth operation. Lubricate if necessary. P.3-45
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-19
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 22

3 - 12
INSP
ADJ
AIR FILTER CLEANING
2. Adjust:
Decompression lever free play
AIR FILTER CLEANING
NOTE:
Proper air filter maintenance is the biggest key
to preventing premature engine wear and
damage.
CAUTION:
Never run the engine without the air filter
element in place; this would allow dirt and
dust to enter the engine and cause rapid
wear and possible engine damage.
1. Remove:
Seat
Fitting bolt 1
Washer 2
Air filter element 3
Air filter guide 4
2. Clean:
Air filter element
Clean them with solvent.
NOTE:
After cleaning, remove the remaining solvent
by squeezing the element.
CAUTION:
Do not twist the element when squeezing
the element.
Leaving too much of solvent in the ele-
ment may result in poor starting. Adjustment steps:
Loosen the locknut 1.
Turn the adjuster 2 in or out until the
adjustment is suitable.
Tighten the locknut.
CAUTION:
After the adjustment, start the engine
and make sure that the engine does not
stop when the handlebar is turned fully
both ways. If the decompression cable is
too tense, the engine will stop by the
decompression system.