Removing Air Suction Valve System: WHY???
#21
08-04-2014, 09:25 PM
Join Date: Jan 2013
Location: Las Vegas, NV
Posts: 1,422
Explain how there is a difference between hot and hot? If your exhaust runs say 1700° with the air injection and runs 1700° with the wrap, what is the difference? If there is any gain with header wrap or ceramic coating to hold exhaust heat to maintain exhaust velocity it seems that the holding of exhaust heat through the air injector would do somewhat the same thing. But it seems no one has actually shown significant gain from either.
The only reason to remove pollution stuff that makes remote sense is the slight weight loss and the elimination of some stuff in the engine area under the fuel tank. There is no performance gain otherwise.
I was going to remove mine, but then when it came down to it, it was easier to just plug everything back in. As for weight - maybe I skip a few second helpings and save more.
The only reason to remove pollution stuff that makes remote sense is the slight weight loss and the elimination of some stuff in the engine area under the fuel tank. There is no performance gain otherwise.
I was going to remove mine, but then when it came down to it, it was easier to just plug everything back in. As for weight - maybe I skip a few second helpings and save more.
Well the difference is that header wrap hold the heat in, which is what heats up the exhaust and helps it flow better. The air injection system heats the exhaust up and because the pipe is open to the outside air all of that heat is coming off the pipe, theoretically being *wasted* in the sense of scavenging the gasses, not to mention burning your legs.
I say get rid of it, it doesn't do anything good, it doesn't REALLY do anything bad, but removing it nets more gain than leaving it on. I waited until my big bore to rip it off, since I was already in there.
Last edited by RockabillSlapMatt; 08-04-2014 at 09:28 PM.
#22
08-05-2014, 01:28 PM
Actually feeding air reduces CO and unburned fuel... Pollutants. It doesn't cost any horsepower either. For that, I'm okay. My choice. If it was hanging off the side of the engine, like XR650Ls do, it would be gone. But where it's at, "it ain't eatin' any oats" so it's easier to just stick it back in there for now.
Fact is I got a few gaskets to see if I can make a block off plate that doesn't cost a fortune. I have to get a quote on cost. What would a fair price be? Remember postage would be maybe two bucks since it would likely weigh more than an ounce probably require shorter screws and gasket.
Fact is I got a few gaskets to see if I can make a block off plate that doesn't cost a fortune. I have to get a quote on cost. What would a fair price be? Remember postage would be maybe two bucks since it would likely weigh more than an ounce probably require shorter screws and gasket.
Last edited by klx678; 08-05-2014 at 01:30 PM.
#23
08-05-2014, 05:54 PM
Join Date: Jan 2013
Location: Las Vegas, NV
Posts: 1,422
Well, i think the key is to not makethe block off plate as thck as bills, not sure why he does that, oerhaps to prevent warpage???? I say $15 is a good price, so ~$17 shipped?
#25
08-05-2014, 10:33 PM
My smog stuff is still on. It doesn't hurt anything and there is no performance to be gained by removing it. Heck, if the OEM muffler wasn't such a restriction and was louder, I wouldn't mind it being a cat converter either. I'm not a tree hugger but unless I get something for it, I don't see the benefit of making things pollute more.
Oh and I ride in shorts all the time. Ride hard even. That dang header pipe is hot so don't touch it. If you don't touch it then it's fine.
Oh and I ride in shorts all the time. Ride hard even. That dang header pipe is hot so don't touch it. If you don't touch it then it's fine.
I'm kind of betting it will burn the snot out of your fingers.
My 650 has no pollution equipment and I can tell you it gets hot too! Anyone actually taken any temp readings or is this guesstimation? Not that it really matters.
#26
08-06-2014, 10:55 PM
Join Date: Mar 2010
Location: South Puget Sound, WA
Posts: 740
You're talking about a 10-20 degree difference in ambient temps compared to a header pipe at what 1000? 1500? degrees. Meh.
#27
08-07-2014, 12:13 AM
Yes Puget sound is where I live and yes we see triple digits. In the 90s just this week. I also ride in Eastern WA where it has been ridden in triple digits while I'm in shorts. Not as often as you Texans but perhaps you're legs are just softer? I do have pretty hairy legs along with moss on my back from all the rain.
You're talking about a 10-20 degree difference in ambient temps compared to a header pipe at what 1000? 1500? degrees. Meh.
You're talking about a 10-20 degree difference in ambient temps compared to a header pipe at what 1000? 1500? degrees. Meh.
#28
08-07-2014, 01:12 AM
It's an old issue in KF.. You don't have to take my word for it - If you research our threads, you'll find the info you need to make your own decision. I'd start by searching for "cherry".
I can save you the research as I've done it long ago.. The air injection system can cause an extra hot secondary burn in the header, especially after fattening up the AFR.
Here is a couple of excerpts from a little research...
Do you still have the fresh air injection system on the bike?...the one that allows air to pass into the exhaust after the combustion chamber to make a secondary burn for cleaner emissions. If the previous owner richened up the mixture to match an exhaust mod, with the stock system on there you could be getting a strong secondary burn in the exhaust with the extra fuel causing extreme exhaust pipe heat.
Otherwise extreme exhaust pipe temps are usually caused by an extremely lean condition, but with the stock system on there, that doesn't sound likely.
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Totally stock 2009 exhaust on my KLX gets ripping hot under normal driving. It stays hot too, long after the bike has cooled down that muffler is still scorching hot. With factory jetting if I run the bike with the choke on to warm it up for a couple of minutes the headpipe will glow red, visible in the dark only.
These new bikes are meant to use the exhaust system as an afterburner combustion chamber. Expect high heat. Not all cats need extra air to reburn the pollutants, I would say most modern vehicles use a cat that requires no air supply to work. Just high temps and pollutants.
In the OP's case, you are running rich with the stock exhaust. If there's enough air then it will be burning in the pipe.
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I can save you the research as I've done it long ago.. The air injection system can cause an extra hot secondary burn in the header, especially after fattening up the AFR.
Here is a couple of excerpts from a little research...
Do you still have the fresh air injection system on the bike?...the one that allows air to pass into the exhaust after the combustion chamber to make a secondary burn for cleaner emissions. If the previous owner richened up the mixture to match an exhaust mod, with the stock system on there you could be getting a strong secondary burn in the exhaust with the extra fuel causing extreme exhaust pipe heat.
Otherwise extreme exhaust pipe temps are usually caused by an extremely lean condition, but with the stock system on there, that doesn't sound likely.
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Totally stock 2009 exhaust on my KLX gets ripping hot under normal driving. It stays hot too, long after the bike has cooled down that muffler is still scorching hot. With factory jetting if I run the bike with the choke on to warm it up for a couple of minutes the headpipe will glow red, visible in the dark only.
These new bikes are meant to use the exhaust system as an afterburner combustion chamber. Expect high heat. Not all cats need extra air to reburn the pollutants, I would say most modern vehicles use a cat that requires no air supply to work. Just high temps and pollutants.
In the OP's case, you are running rich with the stock exhaust. If there's enough air then it will be burning in the pipe.
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Last edited by Klxster; 08-07-2014 at 01:22 AM.
#29
08-07-2014, 01:33 AM
Sorry boys and girls, this thread must have been an unintended consequence of my wanting to remove the smog junk on my bike. Clearly I've started a proxy war via my last thread. I can't pick sides because I've got family up by Highbeam but I love Texas so I'll just sit back and enjoy my over priced Starbucks and moderate 70 degree weather here at home while I watch this unfold.
On a serious note I'll say I like clean air and water like everyone else. It's hard to be a gear head and for the environment when your dealing with internal combustion engines but we don't have to be Eco ******** either. I hate oil leaks, smoke, coolant leaks or just doing things counter productive to making power. I see validity on both sides of the argument.
My two cents
-Big Al
When I say making power I should have said with efficiency comes power. Not running rich or lean and so on, yes you'll always pollute more when you pump up a engine but you can still tune it properly and make it as efficient as possible for what your doing. I see guys, mainly in the automotive world, over fueling cars, running terrible intakes and just doing all kinds of crap that's useless.
On a serious note I'll say I like clean air and water like everyone else. It's hard to be a gear head and for the environment when your dealing with internal combustion engines but we don't have to be Eco ******** either. I hate oil leaks, smoke, coolant leaks or just doing things counter productive to making power. I see validity on both sides of the argument.
My two cents
-Big Al
When I say making power I should have said with efficiency comes power. Not running rich or lean and so on, yes you'll always pollute more when you pump up a engine but you can still tune it properly and make it as efficient as possible for what your doing. I see guys, mainly in the automotive world, over fueling cars, running terrible intakes and just doing all kinds of crap that's useless.
Last edited by NorCalKLX; 08-07-2014 at 01:39 AM. Reason: Add statement
#30
08-07-2014, 12:45 PM
In the street rod world they are getting both more power and clean burn. More and more in the aftermarket automotive area pollution is a concern for manufacturers due to E-checks. They have to make clean burning high performance parts if they want that big street scene sales.
Not so true yet on bikes though.
I don't know if I said it, but the main reason the pollution stuff is still on my bike is because I got lazy.
The cam work is done, valves shimmed, etc and everything is ready to button up... It was easier to stick the pollution stuff back on than to go about plugging this and that up. So I did, knowing it wasn't draining any power. I'm environmentally conscious due to laziness!
Not so true yet on bikes though.
I don't know if I said it, but the main reason the pollution stuff is still on my bike is because I got lazy.
The cam work is done, valves shimmed, etc and everything is ready to button up... It was easier to stick the pollution stuff back on than to go about plugging this and that up. So I did, knowing it wasn't draining any power. I'm environmentally conscious due to laziness!