VFORCE3 VALVE SYSTEM KX250 '05 V307BMoto Tassinari has extracted more power and more performance from our already proven Vforce3 reed valve system design for the 85cc market, by offering the all new Vforce3i with integrated intake boot (included on CR, RM & YZ models only). the Vforce3i shares many of the same features as its legendary big brother, along with these additional unique features Straight Shot newly designed 3i intake boot with centralized opening offers a straight shot