The American Henderson Motorcycle Company was started in 1911, by Tom W and William G.Henderson in Detroit, Michigan. Henderson produced its first motorcycle Henderson 1911 in 1911, with its 934ccm in-line (IOE), or "inlet over exhaust" 4-cylinder motor.

Henderson 1915 Model Four. By 1915 the first production model began rolling off the assembly line. The 1912 model had the designation "4" after the 57ccm inline four-cylinder engine; producing 6hp.

Both brothers stayed with the company, until Arthur O.Lemon stepped in to design 1921s revolutionary Model K, the first motorcycle to use full pressure lubrication. Dreaming of lighter and faster machines, William left the company to form Ace Motor Corporation, and met his untimely end while taking his Ace Sporting Solo for its first test drive Henderson KJ motorcycle.