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Affect of Rad Valve on Jetting?

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Reed valve should not change jetting at all. Have you done a leak down test?

not true at all, i would try 5 less on the main and then go from there.

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How does a reed cange pumping efficiency?

Say your reeds have a crack I'm them or are worn out and have a opening where they should be closed. This will affect how much fuel is getting sucked in therefore your jetting will be for these broken reeds or work out reeds. Putting fresh ones in will act differently (if you had problems with old ones) therefore rejetting will come right after!

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Say your reeds have a crack I'm them or are worn out and have a opening where they should be closed. This will affect how much fuel is getting sucked in therefore your jetting will be for these broken reeds or work out reeds. Putting fresh ones in will act differently (if you had problems with old ones) therefore rejetting will come right after!

Jetting changes to resolve a problem from an unmaintained bike does not make sense.

 

If your house is on fire, you do not open a window if you get hot. You put the fire out. Likewise, worn out reeds get replaced.

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Jetting changes to resolve a problem from an unmaintained bike does not make sense.

If your house is on fire, you do not open a window if you get hot. You put the fire out. Likewise, worn out reeds get replaced.

Yes but a bike can still run on bad reeds! You may not know that your reeds are bad and just keep changing the jetting. Regardless, any time your making a small change in fuel, air, or exhaust you have to rejett for the bike to run to FULL POTENTIAL

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Yes but a bike can still run on bad reeds! You may not know that your reeds are bad and just keep changing the jetting. Regardless, any time your making a small change in fuel, air, or exhaust you have to rejett for the bike to run to FULL POTENTIAL

A man with no legs can run too. You service a bike, fixing what is broken. You do a leak down test on a regular basis to check the health.

You jet for changes in oil/fix mix ratio or changes in air density. You know when you change the ratio or the air density changes. It is not mysterious.

Totally different things.

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A man with no legs can run too. You service a bike, fixing what is broken. You do a leak down test on a regular basis to check the health.

You jet for changes in oil/fix mix ratio or changes in air density. You know when you change the ratio or the air density changes. It is not mysterious.

Totally different things.

Clearly we are not on the same page. We will leave it at that

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Ive often read that reeds alone require different jetting, i assumed a reed valve would require the same?

Id never re-jet to correct a broken reed.

Reed valve (aka 'reeds') rarely require different jetting. Better reeds will make/enable a bike to run 'crisper'. They will not make it faster or make more power. Now a bike with old reeds and then replaced with new, properly working reeds will often appear to be making more power but that is only because the old reeds were shot and you had been making less power. Look at this way (we will assume the rings, seals, powervalve and everything else is always in perfect condition). A bike makes 40hp peak. Reeds wear out, the power drops to 37 very slowly over time, like peeling paint. Finally, you replace the reeds. Suddenly, you are making 40hp again., it feels like you are making more power when in fact, you are just making the power it used to make. New paint does not add square footage to your house, it just makes it seem like a new place.

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Reed valve (aka 'reeds') rarely require different jetting. Better reeds will make/enable a bike to run 'crisper'. They will not make it faster or make more power. Now a bike with old reeds and then replaced with new, properly working reeds will often appear to be making more power but that is only because the old reeds were shot and you had been making less power. Look at this way (we will assume the rings, seals, powervalve and everything else is always in perfect condition). A bike makes 40hp peak. Reeds wear out, the power drops to 37 very slowly over time, like peeling paint. Finally, you replace the reeds. Suddenly, you are making 40hp again., it feels like you are making more power when in fact, you are just making the power it used to make. New paint does not add square footage to your house, it just makes it seem like a new place.

Ok

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Reed valve (aka 'reeds') rarely require different jetting. Better reeds will make/enable a bike to run 'crisper'. They will not make it faster or make more power. Now a bike with old reeds and then replaced with new, properly working reeds will often appear to be making more power but that is only because the old reeds were shot and you had been making less power. Look at this way (we will assume the rings, seals, powervalve and everything else is always in perfect condition). A bike makes 40hp peak. Reeds wear out, the power drops to 37 very slowly over time, like peeling paint. Finally, you replace the reeds. Suddenly, you are making 40hp again., it feels like you are making more power when in fact, you are just making the power it used to make. New paint does not add square footage to your house, it just makes it seem like a new place.

when i said "reed valve" i meant "rad valve"

The all aluminum Boyesen unit seem to have less obstuctions than the stock unit with the goofy plastic block, wich should make for better flow?

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when i said "reed valve" i meant "rad valve"

The all aluminum Boyesen unit seem to have less obstuctions than the stock unit with the goofy plastic block, wich should make for better flow?

The flow restriction is typically the ports and not the reeds. However, you'd have to see flow bench numbers to fairly compare. Keep in mind, too much flow is just as bad as insufficient flow. Everything in an engine has to be sized to work together. For example, imagine a water pipe that was one inch in diameter. You put a section of pipe in to be two inches in diameter then reduce it back down to one inch. Will it flow better? No. The flow at the beginning and end will be the same. What will happen is the velocity at the two inch section will slow down. In some cases, that can cause fuel atomoization to condense for example, and too much vloume on the cranckcase side can reduce the 'supercharging effect' the crankcase and piston provide to pump the charge through the ports and into the barrel. This is whay may engines use 'stuffers'. By the same token, it is possible an engine has too little volume and extra space can improve things. You need to have accurate testing to confirm a change is valid. Sadly, many parts companies main goal is to sell parts. This does not mean the 'RAD Block' is one of them. .

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