Most modern motorcycles have eschewed carburetors for electronic fuel injection, including the old holdouts, Harley-Davidson, who had finally made the switch to fuel injection across the entire product lineup in 2007. Electronic fuel injection might be the norm for most new motorcycles today, but many smaller dirt bikes, older classic vintage models, and customized hot rod bikes, still favor the traditional carbureted setup. In motorcycles that use carburetors, fuel flow is controlled by gravity. Motorcycle fuel tanks are positioned higher than the carburetor. The fuel valve, or fuel petcock, is a small shut-off valve that controls the flow of liquid fuel. Most older designs incorporate a 3-position fuel petcock valve: ON, OFF, and RESERVE. The RESERVE setting is used to access the bottom portion of the fuel tank. This was due to compensate for the lack of a proper fuel gauge. Today’s modern systems use an automatic, vacuum operated petcock that often include a PRIME position as to allow fuel flow into the carburetor without having to fire the engine. A faulty fuel petcock, like any fuel delivery system problem, can cause issues with your bike’s performance. Sputtering, stalling, failure to crank, and poor idle quality are some of the ailments that can be attributed to a bad fuel valve. This relatively simple and inexpensive fix can save you valuable time, effort, and money versus going out and replacing the entire fuel system. HQ Powersports specializes in high quality maintenance parts and performance parts for motorcycles. We stock a full assortment of brand new, OEM-quality aftermarket replacement fuel petcocks for motorcycles by Honda, Kawasaki, Suzuki, and Yamaha.