What is a governor on a four-wheeler?

Child size ATVs generally have governors so that the parent can control the maximum speed a child can reach on the four wheeler. This may be done by adjusting the tension on the throttle so that speed is limited. Another feature some kid's quads have is a tether that a parent can hold while walking behind the machine. If the tether breaks free from the quad, the motor will cease to operate and will stop the machine.

These are the most common forms of ATV governors.