Motorcycle Fuel Petcocks
An integral part of carburetted motorcycles, fuel petcocks, also called fuel taps, are what control the flow of fuel from the fuel tank to the carburettor. Motorcycles with fuel injection systems usually do not have fuel petcocks. If you notice that your motorcycle's petcock is leaking fuel or otherwise not functioning properly, then it may be time to replace it. However, not all fuel petcocks fit all motorcycles.Automatic or Manual Petcocks
Some motorcycles are fitted with manual petcocks. In this case, the user has to manually turn the petcock to the 'On' position to allow fuel flow from the tank. This differs from automatic petcocks. Here, the vacuum created when the engine is turning automatically opens a valve that allows fuel flow. An easy way to identify whether a petcock is automatic or manual is to look at the markings on it. Manual ones have these three positions: Off, On and Reserve; while automatic ones have the following three: On, Prime and Reserve.Size and Direction
The fuel petcock connects to the fuel tank through a threaded hole. Make sure the size of the hole in the tank and the threads of the petcock match. Moreover, some fuel tanks feature the hole on the left-hand side of the tank, while others have it on the right. It is important to use a petcock designed for the correct side, because if you do not, then the petcock's knob will face inward, thereby making it difficult to access.Integrated Filter
Some fuel petcocks feature an integrated fuel filter that prevents dirt and debris from entering the fuel delivery system. While this is good to have in the petcock itself, in case yours does not have a filter, you can always add a separate motorcycle fuel filter to the line between the petcock and the carburettor to achieve the same effect.Original Replacements
If original motorcycle parts for your make and model are available, then they are the best option because you are assured of perfect fit and functionality. Petcocks for popular motorcycle brands, such as Honda, Suzuki and Yamaha, are not difficult to find.