Yamaha YZ450FY 2009 Owner's Service Manual page 172

REMOVING THE ROTOR
1. Remove:
• Nut (rotor) "1"
• Washer
2. Remove:
• Rotor "1"
Use the rotor puller 2.
Rotor puller:
YM-04151/90890-04151
CHECKING THE CDI MAGNETO
1. Inspect:
• Rotor inner surface "a"
• Stator outer surface "b"
Damage→Inspect the crankshaft runout and
crankshaft bearing.
If necessary, replace CDI magneto and/or
stator.
CHECKING THE WOODRUFF KEY
1. Inspect:
• Woodruff key "1"
Damage → Replace.
INSTALLING THE CDI MAGNETO
1. Install:
• Stator "1"
• Screw (stator) "2"
Screw (stator):
10 Nm (1.0 m•kg, 7.2ft•lb)
• Apply the sealant on the grommet of the CDI
magneto lead.
• Tighten the screws using the T30 bit.
YAMAHA Bond No. 1215 (ThreeB-
®
ond No. 1215):
90890-85505
2. Install:
• Woodruff key "1"
• Rotor "2"
• Degrease the contact surfaces of the tapered
portions of the crankshaft and rotor.
• When installing the woodruff key, make sure
that its flat surface "a" is in parallel with the
crankshaft center line "b".
• When installing the rotor, align the keyway "c"
of the rotor with the woodruff key.
4-71
CDI MAGNETO