When setting up your scooter the last operation to make is the transmission calibration. First of all, you have to check that the engine is not defective. If you want to set up a scooter the best thing to do is to buy a POLINI variator. If you have already assembled a standard Polini muffler it is enough to modify the rollers calibration and change with a lighter serie. If you also fit a power unit we suggest adding the gears that let you a better set up of the transmission. If you decide to fit an EVOLUTION cylinder kit it is necessary to fit the corresponding EVOLUTION transmission you find in the POLINI catalogue.