Yamaha YFM660FS Grizzly 4x4 Supplementary Service Manual page 93

GEN
FEATURES
INFO
4WD
When the 4WD mode is selected, the gear motor is operated, and the drive clutch 2 moves to the
right and engages with the left differential side gear 3. Accordingly, power is transmitted as follows:
ring gear 5 → differential pinion gear 4 → left differential side gear 3 → drive clutch 2 → adapter
1 → left front constant velocity joint.
Meanwhile, power from the differential pinion gear 4 is transmitted to the right front constant veloc-
ity joint via the right differential side gear 6.
The ring gear 5 and the drive clutch 2 are not engaged at this time. Therefore, the rotational differ-
ence that occurs between the right and left wheels, while the handlebar is being turned, is absorbed
by the difference in the rotational speeds of the ring gear 5 and the left differential side gear 3.
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