Reed valve

So I have been reading up on reed valves, and was wondering what does it mean when a reed is "digested by the engine"? is this akin to a person digesting a food item, or more like a person digesting, say, a broken reed?

Also, are the performance gains noticeable/worth it? Sounds like the valve basically standardizes your fuel-air mix ratio, no?

Re: Reed valve

thickness and material.

Re: Reed valve

digested by the engine

The reed moves, or flexes, on every intake/exhaust cycle. ALL materials, be they metal, or that new fangled carbon fiber, "fatigue", meaning they have a cycle life, so many "flexes", and they break up/off, and are sucked into the engine. Now you have shrapnel, of one sort, or another, flying about inside your engine, making short work of the bearings. The claim that a carbon fiber reed does not bother anything when it gets sucked in is false, the damage is less, but there is still damage.

A 2 stroke engine has 3 methods of induction: piston port, reed, or disk valve. The advantages to reed induction are: low cost (higher than piston port, lower than disk valve), and a longer induction time than piston port (giving better performance than piston port induction). So generally it gives the best performance for a reasonable cost. Reed valves are a regular service item.

There are some situations that reed valves are not suitable, one is a supercharged/turbocharged situation (2 cycle diesel), where the positive pressure in the intake will hold them open.

Re: Reed valve

What bike do you have?

You can pretty much count on whatever after market reed treats has for your bike is going to be about the best performance jump for the buck.

Along with hi flow filter and hi compression head, reeds are the easiest, cheapest and fastest way to get a little extra zip out of your bike.

And yes, when an engine sucks in its reeds, its more like when the viet cong would grind up glass and put it in coca cola. It would be like a person digesting that.

The dual stage reeds from treats are made of plastic, and I feel like that would be a pretty harmless material to be put through an engine.

Re: Reed valve

_pretty harmless material_

Ball bearings (like what is on your crankshaft) are what is called "zero clearance bearings", meaning: there is a very small amount of room between the balls, and the races, The introduction of ANY foreign material (that the bearing can't smash out of the way) into the bearing causes immediate failure. Reeds are not going to break off at low RPM, maybe your engine will stop before that bearing spins on the crank, or in the case, or maybe it won't.

Reed valves should be replaced @ rebuild time.

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