2000 YAMAHA YZ426F oil

2 - 23
SPEC
ôFit the brake hose into the guide on
the protector.
çFasten the ignition coil lead (in the
sub wire harness) on the upper
inside of the frame and cut off the tie
end.
óPass the ignition coil lead (in the sub
wire harness) under the cushion
bracket (frame).
Fasten the ignition coil lead (in the
sub wire harness) to the frame with
a plastic locking tie.
Pass the carburetor breather hoses
and overflow hose so that all there
hoses do not contact the rear
shock absorber.

CABLE ROUTING DIAGRAM

2 - 24
SPECCABLE ROUTING DIAGRAM
1Clamp
2Ignition coil
3High tension cord
4CDI unit
5CDI unit band
6Throttle cable (pull)
7Throttle cable (return)
8Radiator (left)
9Radiator breather hose
0Radiator (right)
ACDI unit stay (frame)Fasten the ignition coil lead to the
frame with a plastic band.
õFasten the ignition coil and
ground lead to the frame with the
bolt.
‚Pass the ignition coil lead (in the
sub wire harness) so that it does
not contact the carburetor and
rear shock absorber and connect
it with the lead from the ignition
coil on the inside of the frame.
ëPass the throttle cables over the
high tension cord.
äPass the throttle cables along the
outer side of the CDI unit leads.
ìFasten the CDI unit leads to the
frame with a plastic locking tie.
íPass the throttle cables between
the top radiator mounting boss
and middle radiator mounting
boss.îPass the CDI unit leads over the
top radiator mounting boss.
éCross the pull and return throttle
cables before the radiator.
ïPass the throttle cables through
cable guide on the frame.
ðPass the radiator breather hose
between the frame and the radia-
tor without pinching it.
ñPass the radiator breather hose
behind the decompression cable.
÷Insert the CDI unit band over the
CDI unit stay (frame) as far as
possible.

3 - 1
INSP
ADJ

MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
EC310022
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
cc
OIL FILTER
Replace
cc
VALVES
Check the valve clearances.
Inspect
Replace
cc
c
c
The engine must be cold.
Check the valve seats and
valve stems for wear.
VALVE SPRINGS
Inspect
Replace
c
c
Check the free length and
the tilt.
VALVE LIFTERS
Inspect
Replace
c
c
Check for scratches and
wear.
CAMSHAFTS
Inspect
Replace
c
c
Inspect the camshaft sur-
face.
CAMSHAFT SPROCKETS
Inspect
Replace
c
c
Check for wear on the
teeth and for damage.
PISTON
Inspect
Clean
Replace
cc
c
c
Inspect crack
Remove carbon
PISTON RING
Inspect
Replace
c
cc
Check ring end gap
PISTON PIN
Inspect
Replace
c
c
CYLINDER HEAD
Inspect and clean
Retighten
c
Remove carbon
Change gasket
CYLINDER
Inspect and clean
Replace
c
c
Inspect score marks
Inspect wear
CLUTCH
Inspect and adjust
Replace
cc
c
Inspect housing, friction
plate, clutch plate and
spring
TRANSMISSION
Inspect
Replace bearing
c
c
3

3 - 2
INSP
ADJ

MAINTENANCE INTERVALS
SHIFT FORK, SHIFT CAM, GUIDE BAR
Inspect
c
Inspect wear
ROTOR NUT
Retighten
cc
MUFFLER
Inspect
Clean
Replace
cc
cc
* Whichever comes first
CRANK
Inspect and clean
cc
CARBURETOR
Inspect, adjust and clean
cc
When using a high-pres-
sure washer, make sure
that water does not enter
the accelerator pump.
SPARK PLUG
Inspect and clean
Replace
cc
c
DRIVE CHAIN
Lubricate, slack, alignment
Replace
cc
c
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
cc
cc
c
Every two years
OUTSIDE NUTS AND BOLTS
Retighten
cc
Refer to “STARTING AND
BREAK-IN” section in the
CHAPTER 1.
AIR FILTER
Clean and lubricate
Replace
cc
c
Use foam air-filter oil
OIL STRAINER (frame)
Clean
c
FRAME
Clean and inspect
cc
FUEL TANK, COCK
Clean and inspect
cc
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
c
c
c
c
cc
c
c
c
c
c
c
Every one year
FRONT FORKS
Inspect and adjust
Replace oil
Replace oil seal
c
cc
c
c
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
cc
Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube and retighten
c
cc
c
Lithium base grease
CHAIN GUARD AND ROLLERS
Inspect
cc
SWINGARM
Inspect and retighten
cc
RELAY ARM, CONNECTING ROD
Inspect and lube
cc
Lithium base grease
STEERING HEAD
Inspect free play and retighten
Clean and lube
Replace bearing
cc
c
c
Lithium base grease
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate
c
cc
c
c
cc
Lithium base grease
THROTTLE, CONTROL CABLE
Check routing and connection
Lubricate
c
cc
c
Yamaha cable lube or
SAE 10W-30 motor oil ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)
As re-
quiredRemarks

INSP
ADJ

PROGRAMME D’ENTRETIEN
FOURCHE AVANT
Contrôler et régler
Changer l’huile
Changer la bague d’étanchéité
c
cc
c
c
Huile de suspension “01”
BAGUE D’ETANCHEITE ET JOINT
ANTIPOUSSIERE DE FOURCHE
AVANT
Nettoyer et lubrifier
cc
Graisse à base de lithium
AMORTISSEUR ARRIERE
Contrôler et régler
Lubrifier et resserrer
c
cc
c
Graisse à base de lithium
GUIDE-CHAINE ET ROULEAU
Contrôler
cc
BRAS OSCILLANT
Contrôler et resserrer
cc
BRAS RELAIS, BIELLE
Contrôler et lubrifier
cc
Graisse à base de lithium
TETE DE FOURCHE
Contrôler le jeu
Nettoyer et lubrifier
Changer le roulement
cc
c
c
Graisse à base de lithium
PNEU, ROUES
Contrôler la pression de gonflage, le voile
de roue et l’usure des pneus et la tension
des rayons
Resserrer les boulons de la roue dentée
Contrôler les roulements
Changer les roulements
Graisser
c
cc
c
c
cc
Graisse à base de lithium
ACCELERATEUR, CABLES DE COM-
MANDE
Contrôler le cheminement et le branche-
ment
Graisser
c
cc
c
Yamaha lube pour câble ou
Huile moteur SAE 10W-30 PartieAprès
rodageChaque
courseChaque
3ème (ou
500 km)Chaque
5ème (ou
1.000 km)Si
néces-
saireRemarques
3 - 3

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.
EC321000
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator filler 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.1-12
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.3-24 ~ 30
ChainCheck chain slack and alignment. Check that the chain is lubri-
cated properly.P.3-31 ~ 33
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-41 ~ 42
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-42 ~ 43
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-33 ~ 40
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.—
Muffler Check that the muffler is tightly mounted and has no cracks. P.4-3
Sprocket Check that the driven sprocket tightening bolt is not loose. P.3-31
Lubrication Check for smooth operation. Lubricate if necessary. P.3-44
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-17
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-5
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 ~ 21

3 - 7
INSP
ADJ

RADIATOR CAP INSPECTION
CAUTION:

l
Do not mix more than one type of ethyl-
ene glycol antifreeze containing corro-
sion inhibitors for aluminum engine.
l
Do not use water containing impurities or
oil.
7. Install:
l
Radiator cap
Start the engine and warm it up for a
several minutes.
8. Check:
lCoolant level
Coolant level low ® Add coolant. Handling notes of coolant:
The coolant is harmful so it should be han-
dled with special care.
WARNING
lWhen coolant splashes to your eye.
Thoroughly wash your eye with water
and see your doctor.
lWhen coolant splashes to your
clothes.
Quickly wash it away with water and
then with soap.
lWhen coolant is swallowed.
Quickly make him vomit and take him
to a doctor.
EC355000
RADIATOR CAP INSPECTION
1. Inspect:
lSeal (radiator cap) 1
lValve and valve seat 2
Crack/damage ® Replace.
Exist fur deposits 3 ® Clean or
replace.