engine YAMAHA WR 426F 2001 Service Manual

SPEC
2 - 41
CHEMINEMENT DES CABLES
KABELFÜHRUNG
DIAGRAMA DE RUTA DE CABLES
1Gaszug
2Dekompressionshebel
3Lichtschalterkabel
4Kabelbinder
5Dekompressionszug
6Kupplungszug
7Kabelführung
8Tageskilometerzähler
9Bremsschlauch
0Motorstoppschalter-Kabel
Das Motorstoppschalter-Kabel mit
mehrf. verwendb. Kabelbinder am
Lenker befestigen.
õDen Dekompressionszug zwischen
Bremsschlauch und Kupplungszug
führen.
‚Die Gaszüge zwischen obere Gabel-
brücke und Tageskilometerzähler füh-
ren.
ëDie Lichtschalterleitung hinter der Lei-
tung des “MOTORSTOPPSCHAL-
TERS” durchführen, und die Schein-
werferleitung (der Lichtschalterleitung)
vor der Frontröhre verlegen.
äDie Tageskilometerzählerwelle so
montieren, daß ihre Krümmung zum
Rahmnehinterteil weist.
ìDer Metallstutzen des Brems-
schlauchs muß an der Nase des
Hauptbremszylinders anliegen und
die Krümmung nach unten weisen. 1Câble d’accélération
2Interrupteur lumières
3Fil de l’interrupteur lumières
4Bride
5Câble du décompresseur
6Câble d’embrayage
7Guide de flexible
8Compteur de vitesse
9Tuyau de frein
0Fil de bouton d’arrêt du moteur
“ENGINE STOP”
Fixer le fil de bouton d’arrêt du moteur
“ENGINE STOP” au guidon à l’aide
d’une attache en plastique.
õFaire passer le câble de décompression
entre le flexible de frein et le câble
d’embrayage.
‚Faire passer le câbles d’accélération entre
la couronne de guidon et le totalisateur
journalier.
ëFaire passer le fil de commutateur de feux
derrière le fil de bouton d’arrêt de moteur
“ENGINE STOP” et amener le fil de pro-
jecteurs (du fil de commutateur de feux)
devant le tuyau avant.
äMonter le câble du totalisateur journalier
en dirigeant sa partie recourbée vers
l’arrière du cadre.
ìMonter le flexible de frein en veillant à ce
qu’il touche la projection du maître cylin-
dre et que sa partie recourbée soit dirigée
vers le bas.1Cable del acelerador
2Interruptor de las luces
3Cable del interruptor de las luces
4Abrazadera
5Cable de descompresión
6Cable del embrague
7Guía del tubo
8Medidor de trayecto
9Tubo del freno
0Cable del botón de parada del motor
“ENGINE STOP”
Sujetar el cable del botón de parada del
motor “ENGINE STOP” al manillar con
una banda plástica.
õPasar el cable de descompresión entre el
tubo de freno y el cable del embrague.
‚Pasar los cables del acelerador entre la tija
superior del manillar y el medidor de tra-
yecto.
ëPasar el cable del interruptor de las luces
de trás del cable del botón de parada del
motor “ENGINE STOP” y traer el cable
de faro (del cable de interruptor de las
luces) enfrenbe del tubo del cabezal.
äInstalar el cable del medidor de trayecto
de forma que su parte doblada quede
orientada hacia el chasis trasero.
ìInstalar el tubo de freno de forma que
quede en contacto el saliente del cilindro
principal y su parte doblada quede orien-
tada hacia abajo.

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
(300 mi)Every
fifth
or
1,000 km
(600 mi)
As re-
quiredRemarks
ENGINE OIL
Replace
cc
OIL FILTER
Clean
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
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 - 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 filler cap.
Check that the coolant level is correct in the coolant reservoir
tank.
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.1-13
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-14 ~ 18
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-10
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.3-26 ~ 32
ChainCheck chain slack and alignment. Check that the chain is lubri-
cated properly.P.3-33 ~ 35
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-42 ~ 44
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-44 ~ 45
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-35 ~ 42
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. —
Sprocket Check that the driven sprocket tightening bolt is not loose. P.3-33
Lubrication Check for smooth operation. Lubricate if necessary. P.3-46
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-18
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 - 5
INSP
ADJ

EC350000
ENGINE
COOLANT LEVEL INSPECTION
WARNING

Do not remove the radiator cap
1
, drain
bolt and hoses when the engine and radia-
tor are hot. Scalding hot fluid and steam
may be blown out under pressure, which
could cause serious injury.
When the engine has cooled, place a thick
towel over the radiator cap, slowly rotate
the cap counterclockwise to the detent.
This procedure allows any residual pres-
sure to escape. When the hissing sound
has stopped, press down on the cap while
turning counterclockwise and remove it.
CAUTION:

Hard water or salt water is harmful to the
engine parts. You may use distilled water, if
you can’t get soft water.
1. Place the machine on a level place, and
hold it in an upright position.
2. Inspect:
l
Coolant level
Coolant level should be between the
maximum
a
and minimum
b
marks.
Coolant level is below the “LOW” level
line
®
Add soft water (tap water) up to
the proper level.
3. Start the engine and let it warm up for
several minutes.
4. Turn off the engine and check the coolant
level again.
NOTE:

Before checking the coolant level, wait a few
minutes until the coolant settles.
LOWFULLCOOLANT
a
b

COOLANT REPLACEMENT
WARNING

Do not remove the radiator cap when the
engine is hot.
ENGINE/COOLANT LEVEL INSPECTION/
COOLANT REPLACEMENT

3 - 6
INSP
ADJ

COOLANT REPLACEMENT
CAUTION:

Take care so that coolant does not splash
on painted surfaces. If it splashes, wash it
away with water.
1. Place a container under the engine.
2. Remove:
l
Seat
Refer to ”SEAT FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
3. Disconnect:
l
Coolant reservoir hose
1

Drain the coolant completely.
4. Connect:
l
Coolant reservoir hose
LOWFULLCOOLANT1

5. Remove:
l
Engine guard
1

l
Coolant drain bolt
2

6. Remove:
l
Radiator cap
Drain the coolant completely.
7. Clean:
l
Cooling system
Thoroughly flush the cooling system
with clean tap water.
8. Install:
l
Copper washer
l
Coolant drain bolt
l
Engine guard
l
Bolt [engine guard (front)]
l
Bolt [engine guard (rear)]
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..34 Nm (3.4 m · kg, 24 ft · lb)
T R..23 Nm (2.3 m · kg, 17 ft · lb)

3 - 7
INSP
ADJ
COOLANT REPLACEMENT
9. Fill:
lRadiator
lEngine
To specified level.
CAUTION:
lDo not mix more than one type of ethyl-
ene glycol antifreeze containing corro-
sion inhibitors for aluminum engine.
lDo not use water containing impurities or oil.
Recommended coolant:
High quality ethylene glycol
anti-freeze containing
anti-corrosion for
aluminum engine
Coolant 1 and water
(soft water) 2 mixing ratio:
50%/50%
Coolant capacity:
1.2 L (1.06 Imp qt, 1.27 US qt)
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.
10. Install:
lRadiator cap
11. Fill:
lCoolant reservoir tank
Midway a between maximum and min-
imum marks on the tank.
LOWFULLCOOLANTa

3 - 8
INSP
ADJRADIATOR CAP INSPECTION/
RADIATOR CAP OPENING PRESSURE INSPECTION
12. Install:
lCoolant reservoir cap
13. Start the engine and let it warm up for
several minutes.
14. Turn off the engine and inspect the cool-
ant level.
Refer to “COOLANT LEVEL INSPEC-
TION” section.
NOTE:
Before checking the coolant level wait a few
minutes until the coolant settles.
RADIATOR CAP INSPECTION
1. Inspect:
lSeal (radiator cap) 1
lValve and valve seat 2
Crack/damage ® Replace.
Fur deposits 3 ® Clean or replace.
EC356001
RADIATOR CAP OPENING PRESSURE
INSPECTION
1. Attach:
lRadiator cap tester 1 and adapter 2
NOTE:
Apply water on the radiator cap seal.
3Radiator cap
2. Apply the specified pressure.
Radiator cap tester:
YU-24460-01/90890-01325
Adapter:
YU-33984/90890-01352
Radiator cap opening pressure:
110 kPa (1.1 kg/cm2, 15.6 psi)

3 - 11
INSP
ADJ
THROTTLE LUBRICATION
2. Adjust:
lThrottle grip free play
Throttle grip free play adjustment steps:
lRemove the throttle cable cap 1 and
throttle cable cover 2.
NOTE:
lBefore adjusting the throttle cable free
play, the engine idle speed should be
adjusted.
lWhen the motorcycle is accelerating,
throttle cable #1 3 is pulled and throttle
cable #2 4 is pushed.
1st step:
lLoosen the locknuts 5 on throttle cable #2.
lAdjust the free play by changing their
tightening position.
2nd step:
lLoosen the locknuts 6 on throttle cable #1.
lAdjust the free play by changing their
tightening position.
lTighten the locknuts.
WARNING
After adjusting, turn the handlebar to
right and left and make sure that the
engine idling does not run faster.
lInstall the throttle cable cover and throttle
cable cap.
1
2
EC35S002
THROTTLE LUBRICATION
1. Remove:
lRubber cover 1
lThrottle cable cap 2
2. Apply:
lLithium soap base grease
On the throttle cable end a.
3. Install:
lThrottle cable cap
lScrew (throttle cable cap)
lRubber cover
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)

3 - 12
INSP
ADJDECOMPRESSION LEVER ADJUSTMENT/
AIR FILTER CLEANING
DECOMPRESSION LEVER ADJUSTMENT
1. Check:
lDecompression lever free play
2. Adjust:
lDecompression 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.Checking steps:
lRemove the timing plug.
lTurn the crankshaft counterclockwise to
align the T.D.C. mark a on the rotor with
the align mark b on the crankcase cover
when piston is at T.D.C. on compression
stroke.
lCheck the free play c.
Free play:
5 ~ 9 mm (0.20 ~ 0.35 in)
Adjustment steps:
lLoosen the locknut 1.
lTurn the adjuster 2 in or out until the
adjustment is suitable.
lTighten the locknut.
CAUTION:
After the adjustment, start the engine
and make sure that the engine does not
stop when the handlebars are turned
fully both ways. If the decompression
cable is too tense, the engine will stop by
the decompression system.

3 - 13
INSP
ADJ
1. Remove:
lSeat
2. Disconnect:
lTail light lead connectors 1
3. Remove:
lAir filter case cover 2
4. Remove:
lFitting bolt 1
lWasher 2
lAir filter element 3
lFilter guide 4
5. Clean:
lAir filter element
Clean them with solvent.
NOTE:
After cleaning, remove the remaining solvent
by squeezing the element.
CAUTION:
lDo not twist the element when squeezing
the element.
lLeaving too much of solvent in the ele-
ment may result in poor starting.
6. Inspect:
lAir filter element
Damage ® Replace.
7. Apply:
lFoam-air-filter oil or engine mixing oil
To the element.
NOTE:
Squeeze out the excess oil. Element should
be wet but not dripping.
8. Install:
lFilter guide 1
NOTE:
Align the projection a on filter guide with the
hole b in air filter element.
AIR FILTER CLEANING