The sounds of merriment fill the 100,000-square-foot space at Phoenix Indoor Karting where full-sized go-karts speed around a half-mile track and, on a second, remote-controlled trucks race atop imported race clay, careening into the air as they fly over bumps. To compete on this 8,400-square-foot dirt track, racers can bring their own remote-controlled rides or rent a tricked-out Traxxas Slash 4x4 from the facility. On the go-kart track, riders commandeer Bowman karts equipped with electric engines for zero emissions and Decuzzi race tires designed to grip the track on tight turns much more effectively than tires wrapped in Scotch tape. Anyone over the height of 54 inches can ride, as the track keeps junior karts in its fleet. Meanwhile, between races, drivers and spectators can refuel at the onsite grill.