A device used to determine the optimal relationship between the engine’s output and the kart’s wheel speed is essential for maximizing performance. This device provides numerical outputs that indicate the number of engine revolutions required to turn the rear axle once. This calculation involves consideration of the number of teeth on the engine sprocket (driver) and the axle sprocket (driven). For example, a calculation showing a ‘4.0’ outcome suggests that the engine must rotate four times for each single rotation of the rear axle.
Selecting the appropriate numerical relationship is crucial for achieving top speeds and optimal acceleration on a go-kart. A lower number provides faster acceleration but reduces top speed, while a higher number yields a greater top speed but compromises acceleration. Historically, manual calculation was the standard practice, often requiring complex mathematics and experience to estimate adequately. These calculations help to find the ideal balance between acceleration and maximum speed, adapting to various track conditions, driver preferences, and engine characteristics.