Harley-Davidson introduced the Sportster motorcycle family in 1957.
The Sportster was developed as a lighter, sportier model line than Harley-Davidson’s larger touring motorcycles. Its original Ironhead engine was an overhead-valve V-twin, replacing the older K-series engine architecture used immediately before it. The model became one of Harley-Davidson’s longest-running nameplates.
People sometimes confuse the Sportster’s introduction with the later evolution of its engines. The original Sportster used an iron-cylinder-head engine, while the Evolution engine arrived in 1986 and brought major improvements in reliability and performance.
The Sportster name covered many versions over the decades, including standard, custom, roadster, and performance-oriented variants. Its compact dimensions helped it appeal to riders seeking a more manageable Harley-Davidson motorcycle.