Yamaha Raptor 90 2017 Owner's Manual page 4

Your ATV was delivered with an adjustable speed limiter. Yamaha recommends that all beginners start off
to limit the amount of speed available while they learn. The adjusting screw may be gradually turned out
as the beginner becomes more familiar with operating the ATV. Parents should decide when to adjust the
ATV for more power as their youngster's riding skills improve. Once the ATV rider can operate with skill at
the top speed permitted by adjusting the vehicle speed limiter alone, the engine speed limiter plate can be
removed. Since removal of this limiter will result in a significant increase in power, turn the vehicle speed
limiter adjusting screw completely back in again; adjust it out in stages as done previously.
If your child is a beginner or is inexperienced, he or she should take a training course.