Mini 4WD Gear Ratios Explained

Gear ratio converts motor output into wheel speed, and it is the cheapest meaningful tuning change available.

What the numbers mean

A 5:1 ratio turns the wheels once for every five motor revolutions, favouring acceleration. A 3.5:1 ratio favours top speed. Tamiya supplies several ratios as separate gear sets.

Match the ratio to the track

Short, technical layouts with frequent corners want acceleration, so a higher ratio. Long, open layouts with real straights want a lower ratio so the car can actually reach speed.

Mesh quality matters more

A perfectly chosen ratio in a badly meshed drivetrain is slower than a compromise ratio running smoothly. Check that the gears turn freely before changing the ratio at all.

Deburr new gears

Fresh gears often carry moulding flash. Running them in gently, or carefully removing flash, reduces noise and drag from the first lap.