[4] Charles Gustafson left Reading Standard in 1909 and joined Indian as Oscar Hedstrom's assistant.

[4] In late 1915, Indian introduced Gustafson's replacement for Hedstrom's 61-cubic-inch (1,000 cc) V-twin engine.

It was named "Powerplus" because its output of approximately 16 horsepower (12 kW) was noticeably greater than that of the earlier engine.

Three controls were on the right side of the gas tank, a vertically operated shifter, an exhaust valve lifter, and a hand clutch lever.

[2] Between 24 and 28 August 1915, Erwin "Cannonball" Baker rode an early Indian Powerplus from Vancouver to Tijuana in 3 days, 9 hours and 15 minutes, establishing a new "Three Flags" record.