In 1981, Intercontinental A (ICA) was introduced alongside Formula K as a secondary direct-drive class for the European Championship.

Stefano Modena completed back-to-back ICA European Championships in 1984, a feat that would not be repeated until Andrea Kimi Antonelli under OK regulations in 2021.

With the end of KF1 regulations, KF2 became known as simply KF and returned to the World Championship as the primary class once more.

There are eight main technical features of the OK regulations:[3] Engines, chassis, bodywork, brakes and tyres are subject to the homologation system put in place by the CIK-FIA.

Each year, the tyres and the fuel for each category, as well as the KZ and KZ2 carburettor, are chosen after a call for tenders.