Gearbox or shifter karts, are those which include a gearbox of at least 2 different gears, although 6 are more common. Originally engines derived from the motorcycle industry were used however kart specific engines were later developed leading to the development of the KZ international categories under the CIK FIA umbrella which is now utilised in most parts of the world, although in some countries - mainly the America's, categories using motorcycle engines still are prominent. "Gearbox" is a type of drive of kart.