Henderson Model K

The Henderson Model K of 1920 was the first big redesign of the Henderson four after Ignaz Schwinn bought the make and moved it to the Excelsior works in Chicago. Arthur O. Lemon, who had joined Henderson as a salesman in 1915 and then worked in the Excelsior engineering department, is credited with the design. It was heavier, stronger and more reliable than the models before it, with a 79.4 cubic inch (1,301 cc) in-line four-cylinder side-valve engine rated at 18 hp, and a top speed of about 80 mph. The Model K is described as the first motorcycle to use full pressure engine lubrication and the first to offer an optional reverse gear for use with a sidecar. Every frame joint was a steel forging, and the machine had electric lighting and a fully enclosed chain, while the forks and handlebars were shared with the Series 20 Excelsior. William Henderson disliked the heavier direction and left to form the Ace Motor Corporation. The K stayed on sale until 1922, sales rose, and police departments bought it.