Title: B4/Renault MSA Formula KF1 British Championship

Overview: Replaces Formula A and is the fastest direct drive karting class, with many drivers also participating in European and World Karting championships. Also known as the MSA (Motor Sports Association) British Kart Championship.

Driver age: 16 (or 15 with international licence)

Engine: 125cc reed valve TAG. Max 16,000rpm, electric starter.

Drive: Direct drive (no gears), centrifugal clutch.

Tyres: Dunlop DDM

Chassis: CIK homologated

Identification: Yellow plate, black numbers

Format: Timed qualifying determines grid position for two heats; best 24 drivers progress to two finals, both scoring championship points. Finishing order of final one is the grid order for final two. 12 championship races (six events) with the worst two scores (not including disqualifications) dropped.