The Harley-Davidson Servi-Cycle was powered by a 45 c.i. V-twin engine with an accessory tow bar and bumper clamp.
A worker would drive the rig to a customers home or place of business to pick up a car scheduled for service or repair work. The tow bar for the Servi-Cycle was quickly attached to the bumper of the automobile and the vehicle was then driven back to the shop. After work was completed the order was reversed, and afterward, the rider could pick up another vehicle or return to the garage.
This photo is from the Forrest Cadillac dealership at 7033 Forsyth Boulevard in Clayton, Missouri, a suburb of Saint Louis.