A fuel petcock is a small valve used to control the flow of fuel from the tank to the carburetor. This device found particularly on older motorcycle models, and on some other types of small engines like lawnmowers or small, carbureted engines can be manual, requiring you to open and close the petcock to start or stop fuel flow, or vacuum-operated, which automatically controls fuel flow based on the engine’s vacuum. A motorcycle petcock is essential for maintenance and safety, as it allows the rider to shut off the fuel supply when the bike is not in use or during repairs.
