Definition of an ATV According to Wisconsin Law

An ATV is an engine-driven device that:

• Has a net weight of 900 pounds or less and…
• Is 48 inches or less in width and…
• Is equipped with a seat designed to be straddled by the operator and…
• Is designed to travel on three or more low-pressure tires.

A low-pressure tire is a tire that:

• Has a minimum width of six inches and…
• Is designed to be mounted on a rim with a maximum diameter of 12 inches and…
  
• Is designed to be inflated with an operating pressure not to exceed six pounds per square inch as recommended by the manufacturer.
  

This definition includes a small ATV—an all-terrain vehicle that has four wheels and that has either an engine certified by the manufacturer at not more than 90 cubic centimeters or an equivalent power unit.