The CV carburetor is already a pretty good performing piece of equipment that is more than adequate for most street run Harleys. One flaw however is their tendency to have "flat spots" during acceleration. With it's Constant Velocity slide design it requires very little adjustment and it is self compensating when you drive up in higher altitudes. Unlike typical carburetors that may require re-jetting every time you want to take a run to the mountains. This short, to the point DVD demonstrates how easy it is to install a carburetor tuning kit to eliminate those flat spots and increase fuel efficiency and performance.