i was wondering is the exaust wrap made any diffrencein power or if it makes the motor run cooler
exaust wrap
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Other than maybe help keeping some(little if any) heat off of the tank, and surrounding items, harness, I'm not sure doing it on these quads would benifit anything , probably would rust out the header faster if anything. And I doubt you would get the wrap clean!
Get back to school!
I have my toomey ceramic coated but do not have a chromed stock toomey to see if any engine heat or power is achieved!
I do not think it will make you run a hotter motor!
Maybe help the waves bounce faster back to the motor as the sound waves can move faster through hotter temps, good or bad thing? Beyond my experience! *shrugs*
Get back to school!
I have my toomey ceramic coated but do not have a chromed stock toomey to see if any engine heat or power is achieved!
I do not think it will make you run a hotter motor!
Maybe help the waves bounce faster back to the motor as the sound waves can move faster through hotter temps, good or bad thing? Beyond my experience! *shrugs*
It increases the rpm range of your pipe, makes it a screamer when the engine and pipe warm up. Some say it plays havoc with jetting, I don't know that.
It does tend to encourage rust on black pipes and tarnishing on chrome pipes.
It quiets a lot of the "ping" noise.
Sleds (snowmobiles) and the DT200 make use of double pipes to both quiet them down and increase the rpm range when run WOT for several minutes.
I messed with it with my KTM several years ago but found it looked like hell, held water and mud, more trouble than gain.
If I were to run a pipe guard I might try it again. I just used fiberglass cloth.
Steve
well im not gonna worry about rust and i dont care about it holding mud because im gonna be raceing it
Header wrap is really meant for 4-strokes. Here's why. On a 4-stroke you want to eliminate ALL the burned gasses from the cylinder when the piston gets to TDC. More back-pressure means higher pressure inside the cylinder. Thus, less exhaust gas will be expelled. You want to eliminate the spent gasses inside the cylinder, so you will want the backpressure on a 4 stroke to be as low as possible.
Now a 2-stoke on the other hand, you want MORE back pressure since the compression and exhaust stroke are the same. Meaning, your fuel-charged air actually goes into the exhaust pipe, or, "expansion chamber" (vs. header) and then gets sucked back in on the upstroke into the combustion chamber. This is also known as supercharging. That's why 2-strokes with small displacement have more power compared to a 4-stroke.
You want your 2-stoke expansion chamber to stay cooler for more back pressure. You know how when you take a hot shower the curtain starts to suck in? That's because the cooler air outside the shower has more pressure then the hot air inside the shower. Header wrap keeps the header hotter thus, less pressure.
Now a 2-stoke on the other hand, you want MORE back pressure since the compression and exhaust stroke are the same. Meaning, your fuel-charged air actually goes into the exhaust pipe, or, "expansion chamber" (vs. header) and then gets sucked back in on the upstroke into the combustion chamber. This is also known as supercharging. That's why 2-strokes with small displacement have more power compared to a 4-stroke.
You want your 2-stoke expansion chamber to stay cooler for more back pressure. You know how when you take a hot shower the curtain starts to suck in? That's because the cooler air outside the shower has more pressure then the hot air inside the shower. Header wrap keeps the header hotter thus, less pressure.
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Right, need to eliminate ALL the burned gasses, so why don't you cool the exhaust gasses so they will reduce volume and get sucked out of the cylinder like that shower curtain? It is not as simple as all that. Keeping the gasses hot keeps the density down for easy flow and the velocity up for maximum momentum. There is even more...
So why don't we plug off our pipes on a 2 stroke for maximum backpressure and maximum power? Why do we look for free flowing silencers for more power on 2 strokes? Why does an oil soaked silencer kill the power of a 2 stroke?
It is all a balance, the backpressure thing on a 2 stroke. It is a balance of the pipe volume to the stinger diameter and flow. We want the backpressure to increase just at the end of the exhaust cycle, just before the exhaust port closes. We still want minimum back pressure, in fact a vacuum, at the start of the exhaust cycle. This vacuum is created by the momentum of the moving gasses in the stinger pipe, and the tuning dynamics of the pipe shape.
The shower curtain sucks in because the warmed air is less dense and raises and is displaced by the more dense outside cooler air.
Pipe dynamics on a 2 stroke are very complicated, and involve both flow and sonic tuning. Flow is affected by heat because it increases volume and velocity and reduces density. Sonic tuning is hugely affected because heat changes the speed of sound, effectively increasing the tuned rpm of any given pipe. This effect can be helpful to us because low rpm and load tend to keep the pipe tuned for a lower rpm, while high rpm and load tend to heat the pipe and its gasses so they deliver power at even greater rpm. Heat wrap and retarded timing both help this effect.
Right, need to eliminate ALL the burned gasses, so why don't you cool the exhaust gasses so they will reduce volume and get sucked out of the cylinder like that shower curtain? It is not as simple as all that. Keeping the gasses hot keeps the density down for easy flow and the velocity up for maximum momentum. There is even more...
So why don't we plug off our pipes on a 2 stroke for maximum backpressure and maximum power? Why do we look for free flowing silencers for more power on 2 strokes? Why does an oil soaked silencer kill the power of a 2 stroke?
It is all a balance, the backpressure thing on a 2 stroke. It is a balance of the pipe volume to the stinger diameter and flow. We want the backpressure to increase just at the end of the exhaust cycle, just before the exhaust port closes. We still want minimum back pressure, in fact a vacuum, at the start of the exhaust cycle. This vacuum is created by the momentum of the moving gasses in the stinger pipe, and the tuning dynamics of the pipe shape.
The shower curtain sucks in because the warmed air is less dense and raises and is displaced by the more dense outside cooler air.
Pipe dynamics on a 2 stroke are very complicated, and involve both flow and sonic tuning. Flow is affected by heat because it increases volume and velocity and reduces density. Sonic tuning is hugely affected because heat changes the speed of sound, effectively increasing the tuned rpm of any given pipe. This effect can be helpful to us because low rpm and load tend to keep the pipe tuned for a lower rpm, while high rpm and load tend to heat the pipe and its gasses so they deliver power at even greater rpm. Heat wrap and retarded timing both help this effect.
Nice, I like details. I was just trying to keep it simple for this 15 year old kid. But I (and many others on here) appreciate details like sonic tuning, etc. That's what the forum is for, to discuss!
I liked your illustration. Some of us are visual learners. Unfortunately for me I think I over-saturated my memory. But that may explain why I can't seem to remember a damn thing my wife says!
15 year old kids are pretty sharp these days. You don't have to tone it down for them, they get it darned fast! 
Little buggers, usually pretty good on the riding skills too.
Luckily the cunning and treachery of aged experience will usually beat the skill and dexterity of youth!
Little buggers, usually pretty good on the riding skills too.
Luckily the cunning and treachery of aged experience will usually beat the skill and dexterity of youth!
Well now that you mention it.... I was probably a lot smarter when I was 15 than I am now! Trouble is, I had zero common sense. Smart minus common sense equals trouble!
Right, need to eliminate ALL the burned gasses, so why don't you cool the exhaust gasses so they will reduce volume and get sucked out of the cylinder like that shower curtain? It is not as simple as all that. Keeping the gasses hot keeps the density down for easy flow and the velocity up for maximum momentum. There is even more...
So why don't we plug off our pipes on a 2 stroke for maximum backpressure and maximum power? Why do we look for free flowing silencers for more power on 2 strokes? Why does an oil soaked silencer kill the power of a 2 stroke?
It is all a balance, the backpressure thing on a 2 stroke. It is a balance of the pipe volume to the stinger diameter and flow. We want the backpressure to increase just at the end of the exhaust cycle, just before the exhaust port closes. We still want minimum back pressure, in fact a vacuum, at the start of the exhaust cycle. This vacuum is created by the momentum of the moving gasses in the stinger pipe, and the tuning dynamics of the pipe shape.
The shower curtain sucks in because the warmed air is less dense and raises and is displaced by the more dense outside cooler air.
Pipe dynamics on a 2 stroke are very complicated, and involve both flow and sonic tuning. Flow is affected by heat because it increases volume and velocity and reduces density. Sonic tuning is hugely affected because heat changes the speed of sound, effectively increasing the tuned rpm of any given pipe. This effect can be helpful to us because low rpm and load tend to keep the pipe tuned for a lower rpm, while high rpm and load tend to heat the pipe and its gasses so they deliver power at even greater rpm. Heat wrap and retarded timing both help this effect.
im goad you posted that diagram well i want get it then
