KZ2 is a kart racing class using 125 cc water-cooled two-stroke engines yielding about 45 hp. The engines are equipped with a 6-speed gearbox. Technical regulations are similar to KZ1 except for the gearbox which must be "hand-operated and exclusively mechanical without a servo system", and the use of medium tires. Both the engine and chassis must be approved by the CIK-FIA racing governing commission. The class is open to drivers aged 15 and up with the minimum weight being 175kg, this includes the kart and driver.
This class used to be called Intercontinental C (ICC) and was renamed by the CIK-FIA in January 2007.
The class is run in both national and continental championships and is popular in Europe and the USA. In the UK, since the beginning of 2019, The Motorsport UK run championship is the only British Championship and runs to CIK regulations with Le Cont tyres. The NKF Super 4 series continues as KZ UK with a minimum weight of 180kg but has no championship status.
-  – Article 12, Specific Regulations for KZ2 & KZ1, p. 374