If you are a faithful to the Sturgis rally, you know that ambient conditions in the Black Hills vary an extraordinary amount. During the same day riding altitudes can vary from 3500 to over 6500 feet, creating rich conditions that are unnecessary and waste a lot of fuel. Reason why the Thundermax and Zipper’s Performance display at Black Hills Harley-Davidson in Rapid City is always jammed with riders impatient to get their bikes equipped with the “ThunderMax® Auto Tune.”
This system automatically correct ambient variables as you ride, increasing your engine’s efficiency while working to keep your engine running cooler. To help you cruise the Black Hills worry-free, the ThunderMax® crew will be set up on the parking lot of Black Hills Harley-Davidson Rapid City and ready to work as early as July 30th through August 13th, 2011, and I recommend that you set up an appointment in advance by calling 410-579-2828. Zippers Performance Products.