Reed Valve

[Chiron TL-34]

I constantly read about these "reed valves" on this forum, and I have absolutely no idea what they are. After looking at pictures, it just looks like some intake header. I've also read that it is necessary to get a windowed piston, but I also have no concept of what those are. Can someone please explain what these are and their functionality?

 

[Chainlube]

The reed opens and closes as the fuel mixture flows through the carb, and won't let the gas go back out the carb. A windowed piston makes the new charge bigger.

 

[ImpulseRocket]

I constantly read about these "reed valves" on this forum, and I have absolutely no idea what they are. After looking at pictures, it just looks like some intake header. I've also read that it is necessary to get a windowed piston, but I also have no concept of what those are. Can someone please explain what these are and their functionality?

Either a windowed piston, or intake durations exceeding around 150 degrees, a reed valve is required. The windowed piston is often used to achieve the same effect as the large intake duration, but without needing to have such a large intake port, which may not always be possible for reliability or function reasons.

Chainlube covered the function. Think of it like a check valve, or if you are an electronics person, a diode. Only allows the intake to flow one direction.