Powersports Valves & Valvetrain Parts

Depending on the type of your engine, it has one or two inlet and outlet valves per cylinder. The first ones open to allow the air/fuel mixture to get into the cylinder and initiate the combustion process, while the other ones are meant to guide exhaust gases away from the engine. Both inlet and outlet valves are engineered to open at a precise time to ensure smooth and efficient operation of your engine. The gap that appears when the valve is opened should also be of correct size, so that the right amount of the mixture enters the cylinder.

When the engine is running, the camshaft rotates and pushes the right valve to open it. To do this, the camshaft must negotiate the resistance of the valve spring which keeps the valve raised (closed). The spring is very strong to ensure no gap exists between the valve and the cylinder when the valve is closed. If it gets damaged, the valve will stay opened as long as the engine is running, which may not only reduce the compression, but also cause damage to the valve, so the failed spring must be replaced as soon as possible.

Each valve is perfectly straight to ensure smooth and easy movements inside the cylinder head. However, overheating, improper timing or a cracked spring may damage or misform the valve, so it will not be able to do its job properly. Since it is next to impossible to fix a bent or damaged valve, the only way to solve the problem is to replace the failed valve. However, if even one of your valves is damaged, it is recommended to replace all the valves in the engine to ensure their even wear.