Honda TRX500FA 2006 Owner's Manual page 114

Shifting Gears
The drive mode select switch ( ) is located on the left side of the handle 3
cover.
To select the drive mode, bring the ATV to a complete stop and turn the
drive mode select switch.
The mode will not change if the switch is operated while the vehicle is
moving.
(3)
(3) drive mode select switch
Basic Operation & Riding
105