Beneath the Dark Custom styling lurks a liquid-cooled 750 cc Revolution X V-Twin engine. Traffic has never been beaten harder. Last year, we unleashed a new form of rebellion on the urban grid. The Harley-Davidson Street 750 motorcycle. This is a machine built to let you shred traffic in plenty of infinitely customizable Harley-Davidson Dark Custom style. Liquid-cooled engine. Quick handling. A suspension tuned for rough pavement. Fire up the blacked out engine, send some sound out the blacked out pipes, and get behind the café racer windscreen and go. Consider the traffic whipped.