When we traced the origins of the Sportster motorcycle, we went back as far as the 1929 model WL, a 45 cubic inch middleweight. In 1952, the W models were replaced with the venerable K series, replete with new swing arm rear suspension, foot shift and telescopic forks. The K model engine was a single unit, with just one set of cases that housed the flywheels, crankpin, ears and cams, chain primary drive and the four-speed transmission.
For the next few years, H-D improved upon the K, but ultimately, a new bike was needed to make Harley-Davidson middleweights more competitive. In 1957, the Sportster XL model was introduced. Incorporating some of the engineering of the W and K models, the XL model finally brought overhead valves into the mix. The design sported cast iron cylinder heads and rocker boxes that eventually gave rise to the Shovelhead engine design in 1966.
Soon after came the XLCH, a designation for an off-road, tuned Sportster motorcycle. That bike was marketed nationwide by 1959 and introduced Sportster motorcycle riders to the "peanut" gas tank. Other incarnations showed the versatility of the Sportster platform, such as the dirt track-ready XLR (later replaced by the XR-750 in 1970), the XLCR CafŽ Racer in 1977, the XLS Roadster in 1980, the bare-bones XLX-61 in 1983, and the XLH 883, 1100 and 1200 bikes in the 1980s. The 1984 XR-1000 was one of the most unusual members of the family; it was street-legal bike but hardly looked the part.
The Sportster motorcycles diverse genealogy, reliability, and performance led to its place in motorcycle history. A formidable contender, the Sportster motorcycle will thrill riders for years to come.