To meet the extremely strict Euro 4 emissions control the new models have been fitted with a number of new devices, all controlled by the new CDI / ECU unit. One of the major changes from a tuning perspective is the SAS (Secondary Air System) which essentially electronically controls and additional air supply to the main jet breather unit within the carb – causing the bike to lean out at certain times, therefore using less fuel and contributing less emissions.
The Malossi CDI / ECU does a couple of things. It changes the mapping of the engine timing, and also increases the rev limiter to 15,000rpm (far beyond what any cylinder fitted to this scooter is going to reach). The Malossi unit still fully supports the use of all the factory sensors, and the SAS system, just with some modifications to the way these systems work.