The Harley-Davidson Servi Car...
I have learned a great deal about them in the past six months. This is one of those vehicles that you either love it or hate it- sort of like the Chevrolet El Camino.
They were produced from about 1932 to about 1974. The reason I say "about" is because there is often a difference between calendar year and the vin number of the motorcycle.
They were powered by a Flathead 45 cid V-Twin engine and most were tank shift 3-speeds with a reverse and a foot clutch. They were not a "suicide clutch" but a rocker friction foot clutch.
From the beginning of production to 1958- they were a Springer front fork and the first generation spring type frame. From 1958 to the end of the production run they were a hydraulic fork and the second generation frame to accompany the newer rear shocks.
In 1963 the engine was fitted with an electric starter.
Many Servi Cars were use by police departments for marking tires on parking violator's vehicles and traffic control. Many were operated by female police officers. I can remember that firsthand.