Developed during the Great Depression and authorized for production in 1931, the Knucklehead was Harley-Davidson’s high-stakes gamble to outperform its rival, Indian Motorcycle. Despite early "teething troubles"—including oil leaks and brittle valve springs—it successfully established the template for the modern American V-twin. The Genius Engineering Of Harley-Davidson's Knucklehead

: Approximately 36–40 horsepower, a significant increase for its time. Transmission : Four-speed constant mesh transmission.

: Introduced a dry-sump system with a mechanical oil pump. 📜 Historical Significance

: Originally 61 cubic inches (1,000cc); increased to 74 cubic inches (1,200cc) in 1941.