Gearbox barrel Derbi GPR et Aprilia RS New original gearbox barrel for 50cc motorcycle Derbi Euro 3 with starter for sports Derbi GPR et Aprilia RS4, RS with inverted box. Warning this model is not suitable for trails, supermotard enduros Derbi Senda, Drd Pro, Gilera Smt, Rcr, Aprilia Sx, Rx () Technical