No person shall operate on a highway a vehicle that has greater weight on any tire per inch of width of the tire which is in contact with the surface of the highway, than four hundred (400) pounds, for iron or steel tires, or six hundred (600) pounds, for solid rubber or rubber compounded tires.
Maximum weight on iron and solid tires
KRS § 189.200, under TRAFFIC REGULATIONS -- VEHICLE EQUIPMENT AND STORAGE.
KRS § 189.200