Most of the Laydown guys I know are using the Hoosier 10.5×4.50-6 Enduro Tire on front and rear. The tire seems wider than most 5.0 wide tires and being a sportsman it is plenty of tire to hold the kart. I would mount them on 6″ wide wheels. I have used these at Daytona as well as Hallett, those are two completely different tracks and this setup of tires works great. The controls and opens are using wider tires on the rear.