I have the Polini Corsa 70cc kit. But you have to add a pipe and carb to make it work. I have Leo Vince RR pipe, 30mm carb & intake, Polini gear kit & Polini speed pulley. I tried to tune it myself but it was taking too much time. I had a shop do the tuning and it works super. Since they have all the tools and parts nessary to do the job. Save yourself some frustration and have a shop do the work. My bike currently runs 50mph and that´s not even at 1/2 throttle.