ignition curvesfor vehicles with immobilizer TUNING SPORT – high-performanceProduct descriptionOriginal PIAGGIO CDI units limit the rpm to a certain level in order to restrict the scooters top speed and extend the effective life of engine components, especially on the larger capacity machines. This leads to a quick and easy boost in power and speed being possible through ignition tuning. HPI have replacement CDI units available for many PIAGGIO scooter models which replace the original items completely, Plug & Play!