stiffness: reinforced XL12 pcsProduct descriptionA clutch spring kit produced by STOFFI, for all Vespa smallframe models with a single spring. This clutch replaces the central spring found on the smallframe clutch, this set of springs is suitable with 95% of all common smallframe clutch types. Up to a cylinder capacity of 75cc only six soft springs are necessary, larger capacity engines will require twelve soft springs fitted. Please do not include a pressure plate with a bearing mechanism as they require too much space! We recommend the use of a set of MALOSSI friction plates (#52165210), or another four-plate clutch kit of equivalent quality. If you choose to fit a three-plate clutch then the twelve spring set up is essential. From 12PS we recommend the use of the stiffer springs, the clutch is suitable for engines with a power output of up to 20PS. STOFFI himself uses this clutch type for his scooter racing in the ‘Trofeo Parmakit’ class with 18PS at the rear wheel and it performs