Reed valve

From CycleChaos
Jump to navigation Jump to search

The Reed Inlet Valve is used in two stroke engines and is almost as simple as the Piston Inlet Port but instead substitutes a reed type check valve in the intake tract for the piston controlled port.

The reed valve restricts flow of gases to a single direction and consist of thin flexible metal or fiberglass strips fixed on one end that open and close upon changing pressures across opposite sides of the valve.

Reed valve engines deliver power over a wider RPM range than the piston port types, making them more useful in many applications, such as motorcycles, ATVs, and marine outboard engines. Reed valved engines do not lose fresh fuel charge out of the crankcase like piston port engines do.

Many early two-stroke engines, particularly small marine types, employed a poppet type check valve for the same purpose, but the inertia of the valve made it suitable for low speed use only.

Also see: Rotary Disc Valve and Piston Inlet Port