What can you do to a road king to make it faster and louder?

To make a Harley-Davidson Road King faster, consider upgrading the exhaust system to a high-performance aftermarket option, which can also enhance the sound. Additionally, tuning the engine with a performance ECU or adding a high-flow air intake can improve power output. Installing a more aggressive camshaft and optimizing the bike's gearing can also contribute to increased speed. Always ensure that modifications comply with local noise and emissions regulations.