Curiously, Harley sounds don't raise my hackles the way a loud sport-bike does. What are they, Ducati's or something? There is just something just so shrill about their sound.
Captain Pedantic, swooping in to nitpick with one correction, Citizen: Ducatis run V-twins these days, much like Harleys (though that is where the comparison stops). Ducati did make parallel twins some forty years ago, and they were...less than reliable.