Exhaust system Sport GIANNELLI Reverse 31607E for 50ccm standard engines and 70cc sport cylinder. Great in performance, but small in price. The 'Reverse' series has been completely redeveloped by the R & D department. The racing exhaust GIANNELLI Reverse has a handmade case and a damper, which is made of stainless steel and then provided with a Kevlar sheathing. The housing is made of special steel. Very good torque curve and very good performance on 50s and 70s sports cylinders. The best thing, however, is that the racing exhaust is not throttled though has an e-mark and can be used legally in road traffic. Note: of course, as with all performance changes, the variomatic tuning needs to be adjusted as the Racing Exhaust alters the torque and shifts the optimal shift point. The main nozzle should be installed about 10% larger than originals.