torque YAMAHA WR 400F 2002 User Guide

2 - 32
SPECMAINTENANCE SPECIFICATIONS (WR400F)
NOTE:
1. First, tighten the ring nut approximately 38 Nm (3.8 m • kg, 27 ft • lb) by using the ring nut
wrench, then loosen the ring nut one turn.
2. Retighten the ring nut 7 Nm (0.7 m • kg, 5.1 ft • lb). Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Handle crown and outer tube M8 × 1.25 4 23 2.3 17
Under bracket and outer tube M8 × 1.25 4 20 2.0 14
Handle crown and steering shaft M24 × 1.0 1 145 14.5 105
Handlebar holder (upper) M8 × 1.25 4 28 2.8 20
Steering ring nut M28 × 1.0 1 Refer to NOTE.
Front fork and cap bolt M48 × 1.0 2 30 3.0 22
Front fork and base valve M30 × 1.0 2 55 5.5 40
Cap bolt and damper rod (front fork) M12 × 1.25 2 29 2.9 21
Bleed screw (front fork) and cap bolt M5 × 0.8 2 1 0.1 0.7
Front fork and protector M6 × 1.0 6 10 1.0 7.2
Meter cable holder and protector M5 × 0.8 2 4 0.4 2.9
Front fork and brake hose holder M6 × 1.0 2 10 1.0 7.2
Front fork and hose cover M8 × 1.25 1 16 1.6 11
Front fork and hose cover M6 × 1.0 1 7 0.7 5.1
Throttle cable cap M5 × 0.8 2 4 0.4 2.9
Clutch lever holder M5 × 0.8 2 4 0.4 2.9
Clutch lever mounting M6 × 1.0 1 2 0.2 1.4
Decompression lever holder and protector M5 × 0.8 2 4 0.4 2.9
Lights switch M4 × 0.7 2 2 0.2 1.4
Front brake master cylinder and bracket M6 × 1.0 2 9 0.9 6.5
Front brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
Brake lever mounting (bolt) M6 × 1.0 1 6 0.6 4.3
Brake lever mounting (nut) M6 × 1.0 1 6 0.6 4.3
Brake lever position locknut M6 × 1.0 1 5 0.5 3.6
Hose guide (front brake hose) M5 × 0.8 2 4 0.4 2.9
Front brake hose union bolt (master cylinder) M10 × 1.25 1 30 3.0 22
Front brake hose union bolt (caliper) M10 × 1.25 1 30 3.0 22
Front brake caliper and front fork M8 × 1.25 2 23 2.3 17
Brake caliper (front and rear) and pad pin plug M10 × 1.0 1 3 0.3 2.2
Brake caliper (front and rear) and pad pin M10 × 1.0 1 18 1.8 13
Brake caliper (front and rear) and bleed screw M8 × 1.25 1 6 0.6 4.3
Front wheel axle and nut M16 × 1.5 1 105 10.5 75
Front wheel axle holder M8 × 1.25 4 23 2.3 17
Front brake disc and wheel hub M6 × 1.0 6 12 1.2 8.7
Rear brake disc and wheel hub M6 × 1.0 6 14 1.4 10
Brake pedal mounting M8 × 1.25 1 26 2.6 19
Rear brake master cylinder and frame M6 × 1.0 2 10 1.0 7.2
Rear brake reservoir tank and frame M6 × 1.0 1 10 1.0 7.2
Rear brake hose union bolt (caliper) M10 × 1.25 1 30 3.0 22
Rear brake hose union bolt (master cylinder) M10 × 1.25 1 30 3.0 22

2 - 33
SPECMAINTENANCE SPECIFICATIONS (WR400F)
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Rear wheel axle and nut M20 × 1.5 1 125 12.5 90
Driven sprocket and wheel hub M8 × 1.25 6 42 4.2 30
Nipple (spoke)—72 3 0.3 2.2
Disc cover and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Protector and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Engine mounting:
Engine bracket and frame M8 × 1.25 7 34 3.4 24
Engine and frame (front) M10 × 1.25 1 69 6.9 50
Engine and frame (upper) M10 × 1.25 1 55 5.5 40
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine guard (left and right) M8 × 1.25 2 23 2.3 17
Pivot shaft and nut M16 × 1.5 1 85 8.5 61
Relay arm and swingarm M14 × 1.5 1 80 8.0 58
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame and frame M8 × 1.25 3 29 2.9 21
Swingarm and brake hose holder M5 × 0.8 4 1 0.1 0.7
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Drive chain tensioner mounting (upper) M8 × 1.25 1 19 1.9 13
Drive chain tensioner mounting (lower) M8 × 1.25 1 20 2.0 14
Chain support and swingarm M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank mounting M6 × 1.0 2 10 1.0 7.2
Fuel tank and fuel cock M6 × 1.0 2 7 0.7 5.1
Fuel tank and seat set bracket M6 × 1.0 1 7 0.7 5.1
Fuel tank and hooking screw (fitting band) M6 × 1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M6 × 1.0 4 7 0.7 5.1
Seat mounting M8 × 1.25 2 23 2.3 17
Side cover mounting M6 × 1.0 2 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 4 4 0.4 2.9
Air scoop and radiator panel (lower) M6 × 1.0 2 4 0.4 2.9
Front fender mounting M6 × 1.0 4 7 0.7 5.1
Rear fender and air filter case M6 × 1.0 2 7 0.7 5.1
Rear fender and frame (right) M6 × 1.0 1 10 1.0 7.2
Headlight stay (lower) and under bracket M8 × 1.25 2 7 0.7 5.1
Headlight (left and right) M6 × 1.0 2 10 1.0 7.2
Headlight (lower) M6 × 1.0 1 7 0.7 5.1
Tail light M6 × 1.0 3 4 0.4 2.9
Tail light lead clamp and rear fender M4 × 1.59 2 1 0.1 0.7
Coolant reservoir tank (front) M6 × 1.0 1 7 0.7 5.1
Coolant reservoir tank (rear) M6 × 1.0 1 11 1.1 8.0
Sidestand bracket and frame M10 × 1.25 2 66 6.6 48
Sidestand mounting M10 × 1.25 1 64 6.4 46

2 - 34
SPECMAINTENANCE SPECIFICATIONS (WR400F)
EC212300
ELECTRICAL
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Magneto-model (stator)/manufacturer 5NG-50/YAMAHA ----
Source coil 1 resistance (color) 640 ~ 960 Ω at 20 ˚C (68 ˚F)
(Green – Brown)----
Source coil 2 resistance (color) 464 ~ 696 Ω at 20 ˚C (68 ˚F)
(Green – Pink)----
Lighting coil resistance (color) 0.16 ~ 0.24 Ω at 20 ˚C (68 ˚F)
(Black – Yellow)----
Pickup coil resistance (color) 248 ~ 372 Ω at 20 ˚C (68 ˚F)
(White – Red)----
CDI unit-model/manufacturer 5GS-A0/YAMAHA ----
Ignition coil:
Model/manufacturer 5BE-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary winding resistance 0.20 ~ 0.30 Ω at 20 ˚C (68 ˚F) ----
Secondary winding 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
Ignition coil M6 × 1.0 2 7 0.7 5.1

2 - 35
SPEC
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
A
(Nut)B
(Bolt)TORQUE SPECIFICA-
TION
Nm m•kg ft•lb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3 meter
10-2 meterLength
Length
kg kilogram 10
3 gram Weight
N Newton 1 kg × m/sec
2 Force
Nm
m • kgNewton meter
Meter kilogramN × m
m × kgTorque
Torque
Pa Pascal N/m
2Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3 Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute—Engine speed
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS

3 - 46
INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
Tighten the ring nut 3 using ring nut
wrench 4.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YU-33975/90890-01403
T R..
Ring nut (initial tightening):
38 Nm (3.8 m • kg, 27 ft • lb)
Loosen the ring nut one turn.
Retighten the ring nut using the ring nut
wrench.
WARNING
Avoid over-tightening.
T R..
Ring nut (final tightening):
7 Nm (0.7 m • kg, 5.1 ft • lb)
Check the steering shaft by turning it lock
to lock. If there is any binding, remove the
steering shaft assembly and inspect the
steering bearings.
Install the handle crown 5, steering shaft
nut 6, handlebar 7, handlebar holder 8
and headlight 9.
NOTE:
The upper handlebar holder should be
installed with the punched mark a for-
ward.
Insert the end of fuel breather hose 0 into
the hole of the steering shaft.
CAUTION:
First tighten the bolts on the front side of
the handlebar holder, and then tighten
the bolts on the rear side.
T R..
Steering shaft nut:
145 Nm (14.5 m • kg, 105 ft • lb)
Handlebar upper holder:
28 Nm (2.8 m • kg, 20 ft • lb)
Pinch bolt (handle crown):
23 Nm (2.3 m • kg, 17 ft • lb)
Headlight:
7 Nm (0.7 m • kg, 5.1 ft • lb)

ENG
4 - 14
CARBURATEUR
VERGASER
CARBURADOR
Choke-Schieber
1. Kontrollieren:
Kaltstarter-Tauchkolben 1
Heißstarter-Tauchkolben
(rot) 2
Verschleiß/Beschädigung →
Erneuern.
Beschleunigungspumpe
1. Kontrollieren:
Membran (Beschleuni-
gungspumpe) 1
Feder (Beschleunigungs-
pumpe) 2
Deckel 3
O-Ring 4
Druckstange 5
Rißbildung (Membran)/
Beschädigung → Erneuern.
Verunreinigung → Reinigen.
2. Inspizieren:
Drosselwelle 1
Feder 2
Hebel 1 3
Feder 1 4
Hebel 2 5
Feder 2 6
Schmutz → Säubern
Luftabschaltventil
1. Kontrollieren:
Membran (Luftabschaltven-
til) 1
Feder 2
Deckel 3
O-Ring 4
Rißbildung (Membran)/
Beschädigung → Erneuern.
ZUSAMMENBAU UND MONTAGE
Vergaser
1. Montieren:
Heißstarter- Tauchkolben
(rot) 1
Kaltstarter-Tauchkolben 2 Plongeur de starter
1. Contrôler:
Plongeur de démarrage à froid
1
Plongeur de démarrage à chaud
(rouge) 2
Usure/endommagement →
Remplacer.
Pompe d’accélérateur
1. Contrôler:
Diaphragme (pompe d’accélé-
rateur) 1
Ressort (pompe d’accéléra-
teur) 2
Couvercle de pompe d’accélé-
rateur 3
Joint torque 4
Tige de poussée 5
Déchirure (diaphragme)/
endommagement → Rempla-
cer.
Encrassement → Nettoyer.
2. Inspecter:
Axe de papillon 1
Ressort 2
Levier 1 3
Ressort 1 4
Levier 2 5
Ressort 2 6
Sale → Nettoyer
Clapet de coupure d’air
1. Inspecter:
Membrane (clapet de coupure
d’air) 1
Ressort (clapet de coupure
d’air) 2
Couvercle de clapet de coupure
d’air 3
Joint torique 4
Déchirures (membrane)/
endommagement → Rempla-
cer.
ASSEMBLAGE ET MONTAGE
Carburateur
1. Monter:
Plongeur de démarrage à chaud
(rouge) 1
Plongeur de démarrage à froid
2 Empujador del arrancador
1. Inspeccionar:
Empujador de arranque en frío
1
Empujador de arranque en
caliente (rojo) 2
Desgaste/daños → Reempla-
zar.
Bomba de aceleración
1. Inspeccionar:
Diafragma (bomba de acelera-
ción) 1
Muelle (bomba de acelera-
ción) 2
Tapa de la bomba de acelera-
ción 3
Junta tórica 4
Varilla de empuje 5
Desgarraduras (diafragma)/
daños → Reemplazar.
Suciedad → Limpiar.
2. Inspeccionar:
Eje del acelerador 1
Resorte 2
Palanca 1 3
Resorte 1 4
Palanca 2 5
Resorte 2 6
Sucio → Limpiar.
Válvula de corte de aire
1. Inspeccionar:
Diafragma (válvula de corte de
aire) 1
Muelle (válvula de corte de
aire) 2
Cubierta de la válvula de corte
de aire 3
Junta tórica 4
Desgarraduras (diafragma)/
daños → Reemplazar.
MONTAJE E INSTALACIÓN
Carburador
1. Instalar:
Empujador de arranque en
caliente (rojo) 1
Empujador de arranque en frío
2

ENG
4 - 15
CARBURATEUR
VERGASER
CARBURADOR
2. Montieren:
Hauptluftdüse 1
Leerlaufluftdüse 2
O-Ring 3
Ansaugstutzen 4
T R..5 Nm (0,5 m · kg)
3. Montieren:
Feder 1 1
Hebel 1 2
(zum Hebel 2 3)
HINWEIS:
Sicherstellen, daß die Feder 1 auf
den Anschlag a von Hebel 2 paßt.
4. Montieren:
Feder 2 1
(zum Hebel 2 2)
5. Montieren:
Stößelstangen-Verbin-
dungshebel-Baugruppe 1
HINWEIS:
Sicherstellen, daß der Anschlag a
der Feder 2 in die Vertiefung b am
Vergaser paßt.
6. Montieren:
Unterlegscheibe 1
Sicherungsring 2 2. Monter:
Gicleur d’air principal 1
Gicleur d’air de ralenti 2
Joint torque 3
Raccord d’admission 4 T R..5 Nm (0,5 m · kg, 3,6 ft · lb)
3. Installer:
Ressort 1 1
Levier 1 2
Au levier 2 3.
N.B.:
S’assurer que le ressort 1 s’adapte à la
butée a du levier 2.
4. Installer:
Ressort 2 1
Au levier 2 2.
5. Installer:
Ensemble de levier de timone-
rie de la tige de commande 1
N.B.:
S’assurer que la butée a du ressort 2
rentre dans l’encoche b du carburateur.
6. Installer:
Rondelle ordinaire 1
Circlip 2 2. Instalar:
Surtidor de aire principal 1
Surtidor de aire piloto 2
Junta tórica 3
Junta de admisión 4
T R..5 Nm (0,5 m · kg, 3,6 ft · lb)
3. Instalar:
Resorte 1 1
Palanca 1 2
A palanca 2 3
NOTA:
Asegúrese que el resorte 1 encaje en el
tope a de la palanca 2.
4. Instalar:
Resorte 2 1
A palanca 2 2
5. Instalar:
Conjunto de la palanca de
conexión de la biela de empuje
1
NOTA:
Asegúrese de que el tope a del resorte 2
encaje dentro de la ranura b en el carbu-
rador.
6. Instalar:
Arandela plana 1
Circlip 2

4 - 28
ENG

CAMSHAFTS
2. Install:

Timing chain tensioner
3. Turn:

Crankshaft
Counterclockwise several turns
4. Check:

Rotor “I” mark
Align with the crankcase stationary
pointer.

Camshaft match marks
Align with the cylinder head surface.
Out of alignment
→
Adjust.

Install the clips and camshaft caps
4
.
T R..

Bolt (camshaft cap):
10 Nm (1.0 m • kg, 7.2 ft • lb)
NOTE:

Tighten the bolts (camshaft cap)
5
in a
crisscross pattern.
CAUTION:

The bolts (camshaft cap) must be tight-
ened evenly, or damage to the cylinder
head, camshaft caps, and camshaft will
result.
Installation steps:

While pressing the tensioner rod lightly
with fingers, use a thin screwdriver and
wind the tensioner rod up fully clockwise.

With the rod fully wound and the chain
tensioner UP mark
a
facing upward,
install the gasket
1
and the chain ten-
sioner
2
, and tighten the bolt
3
to the
specified torque.
T R..

Bolt (timing chain tensioner):
10 Nm (1.0 m • kg, 7.2 ft • lb)

Release the screwdriver, check the ten-
sioner rod to come out and tighten the
gasket
4
and the cap bolt
5
to the speci-
fied torque.
T R..

Tensioner cap bolt:
7 Nm (0.7 m • kg, 5.1 ft • lb)

5 - 39
CHASFRONT FORK
26. Tighten:
Cap bolt (locknut) 1
NOTE:
While compressing the fork spring, set the
thin type spanners 2 between the spacer 3
and spring guide 4.
Hold the locknut 5 and tighten the cap bolt
with specified torque.
T R..29 Nm (2.9 m · kg, 21 ft · lb)
27. Install:
Cap bolt 1
To outer tube.
NOTE:
Temporarily tighten the cap bolt.
28. Install:
Protector guide 1
Installation
1. Install:
Front fork 1
NOTE:
Temporarily tighten the pinch bolts (under
bracket).
Do not tighten the pinch bolts (handle crown)
yet.
2. Tighten:
Cap bolt 1
3. Adjust:
Front fork top end a
Front fork top end (standard) a:
Zero mm (Zero in)
T R..30 Nm (3.0 m · kg, 22 ft · lb)

5 - 40
CHASFRONT FORK
4. Tighten:
Pinch bolt (handle crown) 1
Pinch bolt (under bracket) 2
CAUTION:
Tighten the under bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
5. Install:
Brake hose holder 1
Caliper 2
Bolt (caliper) 3
NOTE:
Fit the brake hose holder cut a over the pro-
jection b on the front fork and clamp the brake
hose.
6. Install:
Brake hose holder 1
Bolt (brake hose holder) 2
Protector 3
Bolt (protector) 4
NOTE:
When installing the brake hose holder, pass
the brake hose 5 in front of the axle boss a,
then fit it into the hose groove b so that the
brake hose does not contact the nut (wheel
axle).
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
7. Adjust:
Rebound damping force
NOTE:
Turn in the damping adjuster 1 finger-tight
and then turn out to the originally set position.