Aprilia RS660/Tuono 660/Tuareg 660 Graves Smog Block Off Plate
Graves Motorsports Smog Block Off Plates Graves Motorsports smog block off plates are designed to seal off the ports on the valve cover used by the air injection system (a.k.a smog pumps or AIS). The air induction system (AIS) burns unburned exhaust gases by injecting fresh air (secondary air) into the exhaust port, reducing the emission of hydrocarbons. Once these are capped off the air injection system can be safely removed. These smog block...