Indian Powerplus 1919

1919 Indian Powerplus motorcycle. The Powerplus model was built from 1916 to 1923 by the Hendee Manufacturing Company. Designed by Charles Gustafson, the Powerplus's engine was Indian's first flathead (side valve) engine. In 1923-24, when Indian Chief was introduced, Powerplus was sold under the name of Indian Standard.

"Charles Gustafson left Reading Standard in 1909 and joined Indian as Oscar Hedstrom's assistant. Gustafson had designed side valve "flathead" engines for Reading Standard, which had been the first motorcycle manufacturer in the United States to use a flathead engine in a production motorcycle. When Hedstrom left Indian in 1913, Gustafson became Indian's chief engineer. In late 1915, Indian introduced Gustafson's replacement for Hedstrom's 61-cubic-inch (1,000 cc) V-twin engine. The new engine used side valves instead of the inlet-over-exhaust (IOE) valve layout used in Hedstrom's designs. The flathead engine was quieter and less expensive to manufacture than the earlier IOE engine and needed less maintenance. It was named "Powerplus" because its output of approximately 16 horsepower (12 kW) was noticeably greater than that of the earlier engine. The new engine was installed in the existing frames for Indian V-twin motorcycles, and used existing drivetrain components, tanks, handlebars, and other components. The drive train included a clutch, a kickstarter, and a three-speed gearbox. The standard frame for the Powerplus had a conventional rigid rear wheel mounting, but the Powerplus was also available with Indian's Cradle Spring Frame. Introduced in 1913, the Cradle Spring Frame had a rear swingarm linked to trailing leaf springs." (from Wikipedia)