This is a new set of heavy duty valve springs for use on GSX1100 GSX750, GS1100,GS750 16valve aircooled engines..  see our other listings for many more tGSX1100 tuning parts including dyna coils and ignitions, vance and hines exhausts, taylor ignition leads,mikuni carbs,wiseco pistons and rings,cometic gaskets,web and cam motion performance cams, ape tensioners and heavy duty cylinder studs,stainless race valves,carillo rods. etc.