Valve Set GY6 - B2B Product Page Valve Set GY6 The valve's role is specifically responsible for the input of air into the engine and discharge the exhaust gas after combustion. From the engine structure, it is divided into the intake valve and exhaust valve. The intake valve is generally made of alloy steel, and the exhaust valve is made of heat-resistant alloy. High-performance engine component for optimal combustion. Durable construction using specialized alloys for