A Harley-Davidson Sportster is a popular line of motorcycles, and the horsepower output can vary depending on the specific model and year. Generally, the Sportster models have a range of horsepower between 53 and 65 horsepower. However, it's important to note that these figures can vary slightly depending on factors such as engine modifications, aftermarket components, and the specific configuration of the motorcycle. For the most accurate and up-to-date information, it's recommended to consult the official Harley-Davidson website or refer to the specifications of the particular Sportster model you are interested in.