Original Kart, or OK, is open to drivers aged at least 14 years old.
OK is a CIK-FIA international karting class and the primary direct-drive category in the FIA Karting World and European Championships. Unlike gearbox classes, an OK kart sends engine power directly through the chain without a multi-speed transmission.
The class was introduced in 2016, replacing the KF regulations. Its rules simplified the equipment by removing features such as the electric starter and much of the electronics; OK karts are typically push-started. The class uses a 125cc water-cooled two-stroke engine.
The age limit is easy to confuse with OK-Junior, the related junior class for younger competitors. OK-Junior is designed for drivers roughly 12 to 14, with different technical restrictions, while the senior OK category begins at 14. National events can apply their own licensing details, but the international class definition sets 14 as the minimum age.