Harley-Davidson has used the 40mm Keihin constant velocity (CV) carburetor since 1988 on Sportsters and introduced them in 1990 on the Big Twins. The 1988 model differed from the 1989-and-later carbs ...

ATV Carburetor Adjustment involves tuning your ATV’s carb for maximum performance. How do I know my jetting is off? My ATV bogs down a lot, is jetting to blame? I have performance parts, what now?

Let's paint a picture: You've just stuffed your new engine between the framerails of your hot rod. All the hoses and lines are hooked up. It has fresh oil. Even the screw heads on the accessory ...