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· Super Moderator
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Discussion Starter · #3 ·
He said that the increased delivery ratio is causing a huge change needed in the jetting. Now he has a Lectron and is having to make his own metering rod for it, much leaner than anything they make available. Once he gets the jetting straightened out then he will quantify the power increase.
 

· 1986 Honda TRX 250r
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Its great someone is trying different things. I would question how much it would actually flow though. In my head I see the area behind the single large valve is going to be area of high/low pressures and turbulence. kind of like the difference between a straight through muffler or a "turbo" muffler for a muscle car. its not a straight though path for the air to travel. it has to make a lot of turns and twists. Also you have to remember that valve has to open 10,000 times per minute maybe more. Im doubting it would allow the engine to rev much but hey im no mechanical engineer! I dont recognize what engine this bolts to though. Im comparing to a typical v reed valve 2 stroke engine. Would be love to hear results!
 

· Super Moderator
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Discussion Starter · #5 ·
I know the inventor and he showed me a video of him blasting down the street with it, no problem.
From his description it is creating a higher delivery ratio which is causing a need for the jetting to be much leaner (for the same amount of gasoline ingested). The valve itself is very lightweight and is moved back and forth by the air forces applied to it. Reeds can't utilize the end-of-intake-cycle pressure wave to close it right away which means at high RPM it can take 30 degrees of crank rotation to close, allowing intake reversion. This new valve has no reversion.
 

· 1986 Honda TRX 250r
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2,621 Posts
Interesting! The metal spring loaded valve is a double edge sword in my eyes as you cant get too stiff a spring, or it will resist opening and restrict flow, too soft and it wont close until a reversion occurs. Kind of the same thing with a typical reed valve. I get a kick out of discussing this kind of stuff so dont take my comments as negative! One thing i did as a kid was grab the air compressor blow gun and take a reed valve and try to blow air though it as if the engine were, but without the quick gulps an engine creates. What I found was interesting was how little the reed valve had to be open to flow a LOT of air. the ability of a typical reed valve to flow a lot of air without the petals being open much is what makes them shine i assume. lot of surface area like a pleated air filter. Why moto tassinari had designed he v force reed valve with two set of reed petals instead of the conventional single pair im assuming. More surface area. Great discussion here though im glad you posted this. But you never explained what engine this new reed valve was designed for? maybe were not on the same page!
 

· Super Moderator
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Discussion Starter · #7 ·
the spring is soft because the valve easily catches any reversion to rapidly close it. At low RPM the spring closes it before the reversion would happen.
It's a design that can be sized for any engine although the inventor is testing it on his YZ125. He says he tested it up to 13K RPM, no problem.
 
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