Modify the Sportster engine to get even more horsepower
For most of us, the name Harley-Davidson brings to mind images of power and speed. The company has not suffered economically in the same way as manufacturers have in the European market in the last couple of years, and the Sportster has been in constant production since 1957. But if the speed and the power that you already get from your Sportster are not enough, you can increase it with a few simple modifications. If you have knowledge of motorcycle repair, you can do at least some of these procedures yourself.
1. Replace the standard air filter with a performance version, such as the hypercharger supplied by K&N. A high-flow air filter allows more air to flow through the engine, and improving the air filtration system lets the engine produce more power.
2. Change the carburetor to a fuel injection system (EFI). The upgraded system controls the air/fuel mixture, which results in a better performing engine.
3. Install a performance chip that not only increases the power immediately by automatically controlling the air flow and fuel burn, but also allows for the downloading of further modifications at a later date. However, the software packages can be quite complicated, so this might be one modification best left to a professional.
4. Change the factory exhaust system to a high flow/performance version that expels hot air faster and does not allow it to flow back and contaminate the engine. Increasing the diameter of your exhaust pipe lets the air flow out of your engine quicker, so the engine keeps cooler and produces more power.