2-strokes up to 90cc and 4-strokes up to 150cc in the mini class. Adults MAY ride. All riders must have one brake and a tether kill switch. There is no limit on fuel, length or rear tire. Paddle tires and/or steel blots or steel paddles are ok, (with safety rear fender). 450 stock class = no paddles and no extensions. In stock classes, the top 32 NAHA pro riders may ride in the 450 class ONLY.