What happens when a motorcycle valve is broken?

[VonSawyer]

Motorcycle valve damage will reduce the engine's power. Introduction: The intake valve mainly regulates the opening and closing timing to control the intake air volume. If the intake valve opens too early, the increased air intake will raise the cylinder compression pressure, resulting in insufficient ignition voltage and reduced piston thrust, thereby decreasing engine performance. Conversely, if the intake valve opens too late, the reduced air intake will lower the air-fuel ratio, leading to incomplete combustion, carbon deposits in the cylinder and spark plug, black smoke emissions, increased fuel consumption, and diminished engine power. Related Information: If the intake valve spring breaks, carburetor-equipped engines may produce a coughing sound, and the exhaust pipe may emit a "popping" backfire. The operation of adjacent cylinders may also be affected, causing the engine to lose power. Removing the air filter and placing a hand over the carburetor's intake port will reveal neither suction nor blowing. When removing the spark plug from the cylinder with the broken valve spring, oil traces may be found on the spark plug electrodes.