they give you "rap" if you are being a douche about it, more than likely. In some states, in addition to having a decibel meter reading, the officer can make an aural estimation. If your pipe is being heard 4 city blocks away, that probably a good indicator your system is too loud. Nobody wants to hear loud pipes, Harley, Sportbike, or otherwise. If you are one of those idiots that sits at a light and hocks the throttle, or stunts, or performs other acts that bring attention to themselves... don't be shocked when the Police give you some attention. Stay low key, fly under the radar.