Yamaha 4SH-28199-67 Owner's Manual page 208

With the engine idling, lift the shift pedal to the
1st gear position and then release the parking
brake. Apply the throttle slowly and smoothly.
The centrifugal clutch will engage and you will
start to accelerate. Once the ATV has attained
adequate speed, release the throttle and lift the
shift pedal to the 2nd gear position. Release
the shift pedal and apply the throttle smoothly.
Use this same procedure as you move into the
higher gears. Be sure to coordinate the use of
the throttle and shift pedal properly. If the
throttle is applied too abruptly or if the throttle
is not released during shifting, or if the shift
pedal is not released before applying the throt-
tle, the front wheels may lift off the ground re-
sulting in a loss of directional control. Avoid
higher speeds until you are thoroughly familiar
with the operation of your ATV.
CAUTION:
Do not shift gears without releasing the throt-
tle. Damage to the engine or drive train may
occur.
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