2001 YAMAHA WR 400F Manuale duso (in Italian)

Page 401 of 762

YAMAHA WR 400F 2001  Manuale duso (in Italian) ENG
4 - 33
SOUPAPES ET RESSORTS DE SOUPAPE
VENTILE UND VENTILFEDERN
VÁLVULAS Y MUELLES DE VÁLVULA
AUSBAU
1. Demontieren: 
lTassenstößel 1 
lVentilplättchen 2 
HINWEIS:
Die jeweilige Einbaulage de

Page 402 of 762

YAMAHA WR 400F 2001  Manuale duso (in Italian) 4 - 34
ENGVALVES AND VALVE SPRINGS
INSPECTION
Valve
1. Measure:
lStem-to-guide clearance
Out of specification ® Replace the
valve guide. Stem-to-guide clearance =
valve guide inside diameter a – 
v

Page 403 of 762

YAMAHA WR 400F 2001  Manuale duso (in Italian) ENG
4 - 34
SOUPAPES ET RESSORTS DE SOUPAPE
VENTILE UND VENTILFEDERN
VÁLVULAS Y MUELLES DE VÁLVULA
PRÜFUNG
Ventil
1. Messen:
lVentilschaftspiel
Unvorschriftsmäßig ® Ven-
tilführung erneuern. Ven

Page 404 of 762

YAMAHA WR 400F 2001  Manuale duso (in Italian) 4 - 35
ENGVALVES AND VALVE SPRINGS
Valve guide remover:
Intake 4.5 mm (0.18 in)
YM-4116/90890-04116
Exhaust 5.0 mm (0.20 in)
YM-4097/90890-04097
Valve guide installer:
Intake
YM-4117/90890-04117
Exhau

Page 405 of 762

YAMAHA WR 400F 2001  Manuale duso (in Italian) ENG
4 - 35
SOUPAPES ET RESSORTS DE SOUPAPE
VENTILE UND VENTILFEDERN
VÁLVULAS Y MUELLES DE VÁLVULA
Ventilführungs-Austreiber
Einlaß (4,5 mm)
YM-4116/
90890-04116
Auslaß (5,0 mm)
YM-4097/
90890-040

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YAMAHA WR 400F 2001  Manuale duso (in Italian) 4 - 36
ENGVALVES AND VALVE SPRINGS
5. Measure:
lRunout (valve stem)
Out of specification ® Replace.
NOTE:
lWhen installing a new valve always replace
the guide.
lIf the valve is removed or replaced a

Page 407 of 762

YAMAHA WR 400F 2001  Manuale duso (in Italian) ENG
4 - 36
SOUPAPES ET RESSORTS DE SOUPAPE
VENTILE UND VENTILFEDERN
VÁLVULAS Y MUELLES DE VÁLVULA
5. Messen:
lVentilschaftschlag
Unvorschriftsmäßig ® 
Erneuern.
HINWEIS:
lBeim Einbau eines neuen

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YAMAHA WR 400F 2001  Manuale duso (in Italian) 4 - 37
ENGVALVES AND VALVE SPRINGS
9. Lap:
lValve face
lValve seat
NOTE:
After refacing the valve seat or replacing the
valve and valve guide, the valve seat and
valve face should be lapped.
Lapping s