bike was running perfect with rush exhaust .pulled them off and put the Kerker stout 4 inch on and now it is running like really bad ---jumping and lurching on takeoff but runs like a scalded dog after you get it above 40 mph.tried them once before about one month ago same result.my bike is an 08 flhx streetglide fuel injected and i am thinking it has to do with the computer.-thanks in advance for all info