oil pressure YAMAHA WR 426F 2001 Betriebsanleitungen (in German)

2 - 3
SPEC

GENERAL SPECIFICATIONS (WR426F)
Tire:
Type With tube
Size (front) 80/100-21 51M (USA, CDN, ZA)
90/90-21 54R (EUROPE, AUS, NZ)
Size (rear) 110/100-18 64M (USA, CDN, ZA)
130/90-18 69R (EUROPE, AUS, NZ)
Tire pressure (front and rear) 100 kPa (1.0 kg/cm
2

, 15 psi)
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto

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SPEC

MAINTENANCE SPECIFICATIONS (WR426F)
Lubrication system:
Oil filter type Wire mesh type ----
Oil pump type Trochoid type ----
Tip clearance “A” 0.12 mm or less
(0.0047 in or less)0.20 mm
(0.008 in)
Tip clearance “B” 0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)0.24 mm
(0.009 in)
Side clearance 0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)0.17 mm
(0.007 in)
Bypass valve setting pressure 40 ~ 80 kPa (0.4 ~ 0.8 kg/cm
2

,
5.69 ~ 11.38 psi)----
Cooling:
Radiator core size
Width 117.8 mm (4.6 in) ----
Height 260 mm (10.2 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure110 kPa (1.1 kg/cm
2

, 15.6 psi)----
Radiator capacity (total) 0.76 L (0.67 lmp qt, 0.80 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit

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SPEC

MAINTENANCE SPECIFICATIONS (WR426F)
Item Standard
Lubrication chart:
Pressure feed
Splashed scavenge
Oil strainer
Oil pan Oil pump rotor 2
Oil pump rotor 1
Oil tank
Oil filter
Check ball
Cylinder head
Crank pinPiston pinPiston
Drive axleMain axleTransmission gears
Camshaft
Valve lifter

2 - 13
SPECMAINTENANCE SPECIFICATIONS (WR426F)
EC212201
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension: USA, CDN
AUS, NZ, ZAEUROPE
Front fork travel 300 mm
(11.8 in)¬----
Fork spring free length 460 mm
(18.1 in)¬455 mm (17.9 in)
Spring rate, STD K = 4.51 N/mm
(0.46 kg/mm,
25.8 lb/in)K = 4.12 N/mm
(0.42 kg/mm,
23.5 lb/in)----
Optional spring/spacer Yes¬----
Oil capacity 573 cm
3
(20.2 lmp oz,
19.4 US oz) 583 cm3
(20.5 lmp oz,
19.7 US oz)----
Oil level 135 mm
(5.31 in)125 mm
(4.92 in)----

(From top of outer tube with inner
tube and damper rod fully com-
pressed without spring.)80 ~ 150 mm
(3.15 ~ 5.91 in)¬----
Oil grade Suspension oil
“01”¬----
Inner tube outer diameter 46 mm (1.81 in)¬----
Front fork top end Zero mm
(Zero in)¬----
Rear suspension: USA, CDN,
AUS, NZ, ZAEUROPE
Shock absorber travel 132 mm
(5.20 in)¬----
Spring free length 260 mm
(10.24 in)¬----
Fitting length 241 mm
(9.49 in)244 mm
(9.61 in)----
240.5 ~ 258.5 mm
(9.47 ~ 10.18 in)¬----
Spring rate, STD K = 49.0 N/mm
(5.00 kg/mm,
280.0 lb/in)K = 47.0 N/mm
(4.80 kg/mm,
268.8 lb/in)----
Optional spring Yes¬----
Enclosed gas pressure 1,000 kPa
(10 kg/cm
2,
142 psi)¬----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)

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SPECMAINTENANCE SPECIFICATIONS (WR400F)
Lubrication system:
Oil filter type Wire mesh type ----
Oil pump type Trochoid type ----
Tip clearance “A” 0.12 mm or less
(0.0047 in or less)0.20 mm
(0.008 in)
Tip clearance “B” 0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)0.24 mm
(0.009 in)
Side clearance 0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)0.17 mm
(0.007 in)
Bypass valve setting pressure 40 ~ 80 kPa (0.4 ~ 0.8 kg/cm
2,
5.69 ~ 11.38 psi)----
Cooling:
Radiator core size
Width 117.8 mm (4.6 in) ----
Height 260 mm (10.2 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure110 kPa (1.1 kg/cm
2, 15.6 psi)----
Radiator capacity (total) 0.76 L (0.67 lmp qt, 0.80 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit

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SPECMAINTENANCE SPECIFICATIONS (WR400F)
Item Standard
Lubrication chart:
Pressure feed
Splashed scavenge
Oil strainer
Oil pan Oil pump rotor 2
Oil pump rotor 1
Oil tank
Oil filter
Check ball
Cylinder head
Crank pinPiston pinPiston
Drive axleMain axleTransmission gears
Camshaft
Valve lifter

2 - 30
SPECMAINTENANCE SPECIFICATIONS (WR400F)
EC212201
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension: USA, CDN
AUS, NZ, ZAEUROPE
Front fork travel 300 mm
(11.8 in)¬----
Fork spring free length 460 mm
(18.1 in)¬455 mm (17.9 in)
Spring rate, STD K = 4.51 N/mm
(0.46 kg/mm,
25.8 lb/in)K = 4.12 N/mm
(0.42 kg/mm,
23.5 lb/in)----
Optional spring/spacer Yes¬----
Oil capacity 573 cm
3
(20.2 lmp oz,
19.4 US oz) 583 cm3
(20.5 lmp oz,
19.7 US oz)----
Oil level 135 mm
(5.31 in)125 mm
(4.92 in)----

(From top of outer tube with inner
tube and damper rod fully com-
pressed without spring.)80 ~ 150 mm
(3.15 ~ 5.91 in)¬----
Oil grade Suspension oil
“01”¬----
Inner tube outer diameter 46 mm (1.81 in)¬----
Front fork top end Zero mm
(Zero in)¬----
Rear suspension: USA, CDN,
AUS, NZ, ZAEUROPE
Shock absorber travel 132 mm
(5.20 in)¬----
Spring free length 260 mm
(10.24 in)¬----
Fitting length 241 mm
(9.49 in)244 mm
(9.61 in)----
240.5 ~ 258.5 mm
(9.47 ~ 10.18 in)¬----
Spring rate, STD K = 49.0 N/mm
(5.00 kg/mm,
280.0 lb/in)K = 47.0 N/mm
(4.80 kg/mm,
268.8 lb/in)----
Optional spring Yes¬----
Enclosed gas pressure 1,000 kPa
(10 kg/cm
2,
142 psi)¬----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)

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INSP
ADJ

MAINTENANCE INTERVALS
* marked: For USAFRONT FORKS
Inspect and adjust
Replace oil
Replace oil seal
c
cc
c
c
Suspension oil “01”
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube
cc
Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
Retighten
c
cc
cc
(After
rain ride)
c
Molybdenum disulfide
grease
CHAIN GUARD AND ROLLERS
Inspect
cc
SWINGARM
Inspect and retighten
cc
RELAY ARM, CONNECTING ROD
Inspect and lube
cc
Molybdenum disulfide
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
(300 mi)Every
fifth
or
1,000 km
(600 mi)
As re-
quiredRemarks

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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

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INSP
ADJ
PILOT SCREW ADJUSTMENT
10. Install:
lOil filler plug
11. Inspect:
lEngine (for oil leaks)
lOil level
Refer to “ENGINE OIL LEVEL INSPEC-
TION”.
12. Check:
lOil pressure
PILOT SCREW ADJUSTMENT
1. Adjust:
lPilot screw 1
* Except for USAChecking steps:
lSlightly loosen the oil gallery bolt 1.
lStart the engine and keep it idling until oil
starts to seep from the oil gallery bolt. If no
oil comes out after one minute, turn the
engine off so it will not seize.
lCheck oil passages, oil filter and oil pump
for damage or leakage.
lStart the engine after solving the prob-
lem(s) and recheck the oil pressure.
lTighten the oil gallery bolt to specification.
T R..
Oil gallery bolt:
18 Nm (1.8 m • kg, 13 ft • lb)
Adjusting steps:
NOTE:
To optimize the fuel flow at a smaller throttle
opening, each machine’s pilot screw has
been individually set at the factory. Before
adjusting the pilot screw, turn it in fully and
count the number of turns. Record this num-
ber as the factory-set number of turns out.
lTurn in the pilot screw until it is lightly
seated.
lTurn out the pilot screw by the factory-set
number of turns.
Pilot screw:
WR426F: 1-5/8 turns out
* 7/8 turns out
WR400F: 1-1/2 turns out
(example)