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Air cleaner mod. Question?

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Old Feb 16, 2019 | 02:38 AM
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John Imm (John)'s Avatar
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Default Air cleaner mod. Question?


What is done with the air cleaner on a stage one. I don't want to get rid of the paper filter and go the K n M route because of the fine sand here in N. Florida. What else is done .
thanks
 
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Old Feb 16, 2019 | 03:25 AM
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Hi John,

The K&N oiled cotton based filter material will stop particles from reaching your intake just as well if not better than the OEM paper. The main advantage, for me, is that the K&N is a reusable lifetime filter. If you are looking to achieve more airflow, you might want to consider replacing the air cleaner altogether. The Screaming Eagle Ventilator is a nice choice and is very low profile. My knee no longer hits the air cleaner. If you want to stick with the paper element, that is what it comes with. And you should be ok if you change it every 10k. The K&N element is $60.00 more. You will also want to remap with a tuner. Also, if you are increasing the intake airflow, you should think about opening up the restricted exhaust as well. There are many after market products out there. Remember the M8 heads are extremely exhaust sensitive and don't perform well with a muffler over 4". The M8 needs a little back pressure to achieve it's low end torque potential.
 
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Old Feb 16, 2019 | 04:16 AM
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So the street cannons 4 1/2 with stock header pipes are too big?
 
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Old Feb 16, 2019 | 05:06 AM
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Originally Posted by Ridetothehill
Hi John,

The K&N oiled cotton based filter material will stop particles from reaching your intake just as well if not better than the OEM paper. The main advantage, for me, is that the K&N is a reusable lifetime filter. If you are looking to achieve more airflow, you might want to consider replacing the air cleaner altogether. The Screaming Eagle Ventilator is a nice choice and is very low profile. My knee no longer hits the air cleaner. If you want to stick with the paper element, that is what it comes with. And you should be ok if you change it every 10k. The K&N element is $60.00 more. You will also want to remap with a tuner. Also, if you are increasing the intake airflow, you should think about opening up the restricted exhaust as well. There are many after market products out there. Remember the M8 heads are extremely exhaust sensitive and don't perform well with a muffler over 4". The M8 needs a little back pressure to achieve it's low end torque potential.
just curious how you are qualifying these statements

re: K&N, from my experience I 'see' no way they can possibly prevent as much "or better" fine granular silty sediment and airborne contaminants from passing through the filter media as OEM paper. hold them both up to a light source and then look at what collects in a wash tub after cleaning them and it's painfully obvious to come to the conclusion OEM paper traps finer dirt...think people buy into the marketing statements and claims too much

re: muffler size, seems performance discrepancies have more to do with baffle size that OD of mufflers, 4.5" SE Street Canons perform great and provide plenty of "back pressure to achieve it's low end torque potential" so your statement I believe is too general and not entirely accurate
 
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Old Feb 16, 2019 | 06:01 AM
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Originally Posted by mjwebb
just curious how you are qualifying these statements

re: K&N, from my experience I 'see' no way they can possibly prevent as much "or better" fine granular silty sediment and airborne contaminants from passing through the filter media as OEM paper. hold them both up to a light source and then look at what collects in a wash tub after cleaning them and it's painfully obvious to come to the conclusion OEM paper traps finer dirt...think people buy into the marketing statements and claims too much

re: muffler size, seems performance discrepancies have more to do with baffle size that OD of mufflers, 4.5" SE Street Canons perform great and provide plenty of "back pressure to achieve it's low end torque potential" so your statement I believe is too general and not entirely accurate
My thinking is that the oiled element would trap the fine particles; although, this is just my opinion and after some thought, I'm thinking that so would the paper. Washing out each filter to determine which has trapped more dirt is a good idea. If one could have them each on different bikes that have run side by side in the same conditions, this would be an accurate and scientific assessment. As far as the diameter of exhaust, this would very much depend on what is inside the tube, of course, and yes it was a very general statement. The 4.5 Street Cannons might have the right baffling to prevent the inversion that is created with a larger diameter exhaust. So, maybe size doesn't matter.
 
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Old Feb 16, 2019 | 06:02 AM
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The purpose of the aftermarket intake is to get more air in. My original air cleaner was very restricted, for noise purposes. I drilled holes in the backing plate outside of the filter, goal was to get more air to the outside of the filter.
 
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Old Feb 16, 2019 | 09:06 AM
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Originally Posted by Ridetothehill
My thinking is that the oiled element would trap the fine particles; although, this is just my opinion and after some thought, I'm thinking that so would the paper. Washing out each filter to determine which has trapped more dirt is a good idea. If one could have them each on different bikes that have run side by side in the same conditions, this would be an accurate and scientific assessment. As far as the diameter of exhaust, this would very much depend on what is inside the tube, of course, and yes it was a very general statement. The 4.5 Street Cannons might have the right baffling to prevent the inversion that is created with a larger diameter exhaust. So, maybe size doesn't matter.
nah, one only needs to look thru the light source, the paper is so dense, the K&N I can see tiny pin holes of light even and not nearly as dense, just more porous so naturally small micron or whatever gets thru....who knows how much wear or how long or how many miles it would take to make a real world diff tho in these engines, might not matter at all for all I know..I'm just OCD about filters and fluids from starting back in the 70's racing mx, we changed gear oil and air filters after every race weekend...dirt in the engine is the enemy was pounded into my head at an early age and I learned firsthand how much longer a top end lasts on engines that weren't neglected
 
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Old Feb 16, 2019 | 12:17 PM
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I think what you will find is that the K&N improves air flow. This might be done by sacrificing filtration. I looked at a test that was done in 2003 that bore this out. You have to remember that's 15 years that both types of filtration have had a chance to make improvements. Here is the crux of the article.

"Each test filter was used in the same car, on the same roads for 500 miles. The darker deposits indicate poorer filtration, and lighter ones better filtration. That said, both the cotton gauze type (K&N) and foam filters (Amsoil & Jackson Racing) showed the same levels of filtration. Both performed poorly compared to the fiberous or paper filters (Napa, Baldwin, and Mazda)."

" In the end, paper or fiberous filters do remove more particles from the air before they enter your engine. The cotton gauze filters indeed offer better airflow. You have to decide for yourself whether you value every last ounce of power or filtration."

Here is a link to a performance test between stock, aftermarket, and K&N air filters. It was interesting.
https://www.bobistheoilguy.com/forum...-1#Post4925424

Here is a link to aftermarket air cleaner testing that Steve Cole did on the M8. Unfortunately it doesn't show the stock air cleaner, but I do have a dyno that we did when we were cam testing showing the difference between the stock AC and the Arlen Ness Big Sucker for the stock cover that Steve refers to as the S-1 in his tests.

https://www.hdforums.com/forum/milwa...round-2-a.html

Here's that dyno run.



The green is the stock air cleaner and the red is the S-1 Arlen Ness. So you can see as the rpm comes up and more air is needed the S-1, which uses a K&N or K&N type filter is moving more air and getting more power. This was a stock M8 107. The question, is it worth it on a stock motor? Probably not.
 
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Old Feb 19, 2019 | 04:28 AM
  #9  
John Imm (John)'s Avatar
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Originally Posted by Ridetothehill
Hi John,

The K&N oiled cotton based filter material will stop particles from reaching your intake just as well if not better than the OEM paper. The main advantage, for me, is that the K&N is a reusable lifetime filter. If you are looking to achieve more airflow, you might want to consider replacing the air cleaner altogether. The Screaming Eagle Ventilator is a nice choice and is very low profile. My knee no longer hits the air cleaner. If you want to stick with the paper element, that is what it comes with. And you should be ok if you change it every 10k. The K&N element is $60.00 more. You will also want to remap with a tuner. Also, if you are increasing the intake airflow, you should think about opening up the restricted exhaust as well. There are many after market products out there. Remember the M8 heads are extremely exhaust sensitive and don't perform well with a muffler over 4". The M8 needs a little back pressure to achieve it's low end torque potential.
Thanks man...the K&M definitely improves airflow and if lived anywhere else I would use one. In pensacola we have white silicate sand. Much smaller particles. When you take apart a local turbo filtered with a k&m you will see it gets by and eats them up. Never with the paper filter. I'm more wondering if I can route the oil lines from back into the throttle body. I've read that it causes carbon build up on the valves. Does the stage one do that or not .I really like to be a sleeper so I will drill lots of holes in places that are hidden for airflow and I have no cat. Without removing the slip on and shining a light it's undetectable. I don't care about warranty ... anything they can jerk u around on they will anyway so I do everything I can myself I've never had a breakdown. I love my bike now. She was about to get traded for an Indian if the cat removal had not worked so well.

 

Last edited by John Imm (John); Feb 19, 2019 at 04:32 AM.
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