A continuously variable transmission (CVT) is the holy grail of performance for two stroke engines. This is the case for two reasons: the two stroke engine's narrow power band and the CVT's ability to keep it in that power band. Without a variation in the gear ratio, gas scooters experience a very limited range of effective drive ratio. Even though the larger two stroke engines are very powerful, that power is not properly harnessed. What a CVT does is that it allows the engine's RPMs to stay within the power band through the entire acceleration of the scooter. This effects low-end power and high-end speed drastically.

This guide will show you how to modify a Goped GSR40 with a pocket bike continuously variable transmission. This guide is based on the original GSR40_CVT project.