That is a Harley-Davidson going somewhere. The sound that lives behind the rider's ears, the sound assaulting pedestrians on any street corner, the drivers inside any car. The sound of idle made urgent and purposeful and businesslike. As many Harley riders will say, that is not noise. Other bikes make noise.
Machines make noise.
Big trucks and jet planes and buildings collapsing and trees falling in the woods when no one is there make noise. Harley-Davidsons make a sound like no other bike still in business. Other makers can manufacture bikes that look like Harleys, but no one has been willing to invite the vibration in order to produce the sound. It's the vibration that brings up the front wheel on Main Street in Hollister and on the main straight at Daytona. It blasts the leaves at the Rock Store and tears at the smooth warm Sunday afternoon air in Malibu.