Author Topic: Reusable air filters  (Read 858 times)

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Hoiho

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on: April 07, 2021, 03:29:10 am
Given the bad rep K&N and other reusables often get for poor particle filtration; I'm suprised that so many folk install these things in place of the stock filter.

Are most folk at the drag strip each wkd trying to eke out every last micro-hp, or have they just turned a blind eye??

Discuss  ;D


RalphG

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Reply #1 on: April 07, 2021, 03:31:06 am
I've used K&N filters for over 30 years.   No inclination to stop.

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6504me

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Reply #2 on: April 07, 2021, 05:02:38 am
Most problems with K&Ns are the loose nut in front of the filter.

Drying them with compressed air is a BIG no-no. Over oiling is another mistake lots of people make.

Properly cleaned and oiled K&Ns give good service on the street and save $$$ in the long run.


NVDucati

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Reply #3 on: April 07, 2021, 05:18:24 am
Given the bad rep K&N and other reusables often get for poor particle filtration; I'm suprised that so many folk install these things in place of the stock filter.

Are most folk at the drag strip each wkd trying to eke out every last micro-hp, or have they just turned a blind eye??

Discuss  ;D
Honestly, the bad rep that K&N has been given over the last couple of decade has me stumped.
Anyone who really wants to find out about air filters and compare the various types and brands should start with learning about the "Frazier Permeability Test ".
   In respect to everyone's time and because i don't know how many people care I'll just drop a couple of URLs and  snipits as a starting point.
http://frazierinstrument.com/products/fap/fap-description.html
"The Frazier Precision Instrument Company manufactures a Differential Pressure Air Permeability Instrument in three models.  The First model, The Low Pressure Instrument  was developed by the National Institute of Standards and Technology for measuring the air permeability of textile type materials and is the acknowledged standard of the U.S. Government and the U.S. Textile Industry. Frazier, in conjunction with the  U.S. Air Force developed a second model, the High Pressure Instrument on the same principle as the Low Pressure Instrument, but designed it with a much greater versatility of use through its higher attainable air flow and differential pressure. The third model is the Frazier 2000TM.      Model Comparison Chart

The Frazier 2000® is the next generation of Frazier Differential Pressure Air Permeability Instruments.  This new instrument builds on Frazier's well-known reputation and implements electronic pressure sensing as well as computerized logging and manipulation of the electronic measurements.  The Frazier 2000® brings a whole new era of reliability and productivity to the field of permeability testing and measurement.  The Frazier 2000® has all the same features of High Pressure Permeability Instrument in addition to those listed. (Additional Information about the Frazier 2000) The Frazier 2000 requires the use of a Windows based personal computer not included."


https://www.knfilters.com/efficiency_testing.htm
"K&N operates an in-house filtration test lab with two different testing machines built in consultation with Southwest Research Institute, one of the pre-eminent testing companies in the world. Most of the filtration testing we perform on our air filters is performed in our lab that operates on a year round basis. Occasionally, we send air filters out for testing with an independent lab, either to confirm our in-house testing or to reduce the capacity requirements on our lab.
   We perform tests of filters both in the factory air box and in SAE/ISO recommended test housing fixtures. Our goal is to design filters with the maximum possible airflow achievable while providing guaranteed engine protection.
   Our actual air filters when tested generally demonstrate a cumulative filtration efficiency of between 96% and 99%. All this testing we do allows us to guarantee our air filters provide all the protection your vehicle will ever need.
   For a more technical explanation of our filtration test stand procedures see our Efficiency Testing Procedure."

https://www.knfilters.com/efficiency_testing_procedure.htm

https://www.totalmotorcycle.com/downloads/aftermarketfilters-Airfilters#PAPER
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Karl Fenn

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Reply #4 on: April 07, 2021, 10:17:10 am
Well to be honest it's the cost that stops me using them, and also l am not convinced it filters particles and microns as well as the stock filters.


zimmemr

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Reply #5 on: April 07, 2021, 01:42:01 pm
Given the bad rep K&N and other reusables often get for poor particle filtration; I'm suprised that so many folk install these things in place of the stock filter.

Are most folk at the drag strip each wkd trying to eke out every last micro-hp, or have they just turned a blind eye??

Discuss  ;D

 I used K&N filters on most of my dirt trackers, sometimes with a "sock" if it was dusty, more often without one for at least thirty years and never lost an engine due to dirt ingestion. I'd venture to say that among dirt trackers the K&N is probably the most popular filter out there.

 I can also tell you that it's an extremely popular filter in the construction industry. Lot's of earth moving and farming equipment have them installed, normally with a pre-filter, which is standard practice. If your excavator or combine goes down, it's expensive and a huge PITA for everyone involved so nobody skimps on filters,  I think the popularity of the K&N in that instance would speak volumes.

Lastly given the size of the company you'd have to think that they must be doing something right to sell all of those filters.

For the record I have one in my Interceptor and my DR400EZ. And will install one in my Himalayan as soon as it needs one. 8)


GravyDavy

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Reply #6 on: April 07, 2021, 03:58:41 pm
Well to be honest it's the cost that stops me using them, and also l am not convinced it filters particles and microns as well as the stock filters.
I don't know if this is still the case, but they used to advertise airflow measured with a new, clean filter, and filtering effectiveness with a very dirty one.  They didn't specify filtering effectiveness of a new one with all of the big holes that you can clearly see light through, only one that was approaching being clogged.

Once I noticed that, I never looked at them again.  Does anybody know if they are publishing the micron rating of a new, properly oiled one?


Jack Straw

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Reply #7 on: April 07, 2021, 04:10:53 pm
For the last 25 vehicles I've owned I don't think Ive given more than 90 seconds of thought to elfin' air cleaners.
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NVDucati

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Reply #8 on: April 07, 2021, 04:12:37 pm
I don't know if this is still the case, but they used to advertise airflow measured with a new, clean filter, and filtering effectiveness with a very dirty one.  They didn't specify filtering effectiveness of a new one with all of the big holes that you can clearly see light through, only one that was approaching being clogged.

Once I noticed that, I never looked at them again.  Does anybody know if they are publishing the micron rating of a new, properly oiled one?

Geez ... (you're just pulling my leg? Right?)
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GravyDavy

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Reply #9 on: April 07, 2021, 04:23:48 pm
Geez ... (you're just pulling my leg? Right?)

Unfortunately, no.  Those were really their claims in ads and magazine articles. Bear in mind that I'm talking about sometime in the 70's when they were still a new innovation.  A whole lot may have changed since then, but after that first impression I've literally never looked at gauze filters again. I'm not a performance or ultra-mileage rider, so buying a new paper filter every few years just isn't an issue for me.


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Reply #10 on: April 07, 2021, 04:24:32 pm
Seems like most if not all the "bad rap" they get is from people using testing data of dubious relevance while the people who have used them for decades like them and have had no issues. I don't worry about using them and don't get paid to convert others to their use, so I don't worry about them using them either.


BlackIce619

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Reply #11 on: April 07, 2021, 05:19:09 pm
This is a great discussion. I have always used reusable air filters on all my vehicles. It probably has saved me money in the long run for sure, but am going to hang out in this post to see what everyone thinks. If the complaint is about K&N, then I am glad I have the S&S version  :P
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NVDucati

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Reply #12 on: April 07, 2021, 05:44:36 pm
Unfortunately, no.  Those were really their claims in ads and magazine articles. Bear in mind that I'm talking about sometime in the 70's when they were still a new innovation.  A whole lot may have changed since then, but after that first impression I've literally never looked at gauze filters again. I'm not a performance or ultra-mileage rider, so buying a new paper filter every few years just isn't an issue for me.
No worries GravyDavy. I was reacting to your question “Does anybody know if they are publishing the micron rating of a new, properly oiled one?” when I had just, minutes before, posted links to specific, independent information.

I truly get it that none of this might matter, at all, to some folks. But I guess I could have also mentioned that the FAA has certified K&N filtration for aircraft. One supplier cites:
“K&N re-cleanable air filter media
Up to 50% more air flow with the same dirt holding capability
NO ADS (Airworthiness Directive) 
Increased horsepower
Reported fuel savings of .3 to .5 gallons per hour”

A third to a half gallon saved per hour is a big deal for pilots. Not so much as a money saver but for the effect on available range. (from 6000ft you can’t just push your plane to the next gas station) Even if one only looks at it from an ecological viewpoint including the notion of the disposables… it is not just a drag strip thing. Don’t know if that matters.
   Last, how often one changes a air filter is subject to a lot of considerations. One consideration should be that as any air filter gets covered with dust, it creates a vacuum on the fuel intake side. Paper filters are more prone to eventually suck the particles right on through much sooner.
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Hoiho

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Reply #13 on: April 08, 2021, 11:32:27 am
So, this is the problem as i see it: once the oiled-cotton filter gets dirty enough that all the oil dries out, it’s possible for dusty air to make its way through the more porous filter media and into your engine, whereas a paper filter with it's much smaller voids would simply become blocked.

Am I missing something?


viczena

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Reply #14 on: April 08, 2021, 11:35:39 am
Do you want a blocked paper filter or a k&N which is regurlary moisted by the oil from the casevent?
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Hoiho

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Reply #15 on: April 08, 2021, 12:05:51 pm
Neither! Although when a opaque paper filter is blocked it's likely easier to see than deciding when an oiled cotton filter isn't working properly.. if you get my meaning.


viczena

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Reply #16 on: April 08, 2021, 12:10:47 pm
I use K&N for all my bikes. It is easy to see if it is clocked. Brake cleaner, dry with presurized air, thats it. Once a year. Or every 6 month if driving in really dirty conditions.
« Last Edit: April 08, 2021, 12:13:12 pm by viczena »
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Hoiho

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Reply #17 on: April 08, 2021, 12:19:26 pm
I use K&N for all my bikes. It is easy to see if it is clocked. Brake cleaner, dry with presurized air, thats it. Once a year. Or every 6 month if driving in really dirty conditions.

No oil?


viczena

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Reply #18 on: April 08, 2021, 12:21:14 pm
All my bikes have the case vent through the air filter. That is enough oil.
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Hoiho

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Reply #19 on: April 08, 2021, 12:26:03 pm
All my bikes have the case vent through the air filter. That is enough oil.

Interesting. Is that a fault or a modification?


viczena

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Reply #20 on: April 08, 2021, 12:39:23 pm
Its normal.
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ace.cafe

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Reply #21 on: April 08, 2021, 12:40:28 pm
It comes down to surface area.
It won't matter if a filter is 99% effective if there is only one square inch of it.

If a K&N is a full size element with enough surface area to meet the engine's flow needs while filtering the air at 99%, then good. If not, then not good.

Most, if not all, of those "pod" filters that clamp on to the carb or TB are not even near enough surface area, nor do they provide enough free air volume inside the filter barrier for good throttle response or good atmospheric air pressure . If you look at them dirty, you can see that they flow mostly within the first inch, or so, of gauze.

A larger panel filter or round filter with plenty of surface area is much better, whether gauze or paper.
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viczena

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Reply #22 on: April 08, 2021, 12:42:52 pm
You are right, I always use full size filters.

Do you know if the special filter can for UCE 500 from Ace is still available?
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gizzo

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Reply #23 on: April 08, 2021, 12:45:42 pm
I have NFI about the filtering capability of K&N. I don't rate them because the ones I've looked at don't fit the airbox properly. My LS650 and my TRX850 both had them, both didn't fit. I replaced them with OEM filters. My daughter's WRX has one. It doesn't fit properly either.

I'm running the Ace airbox mod with paper filter. I've tried it with and without the element, doesn't make a scrap of difference. IME paper filters do just fine removing dust and reusuable filters are not worth the hassle to me (my dirtbikes, sure. Oiled foam. It's very dusty where I ride. If I were tootling through the Black Forest I doubt I'd even need an air cleaner).

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ace.cafe

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Reply #24 on: April 08, 2021, 12:53:10 pm
You are right, I always use full size filters.

Do you know if the special filter can for UCE 500 from Ace is still available?
Unfortunately, I had to discontinue that item due to parts supplier issues.
 :(
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Karl Fenn

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Reply #25 on: April 08, 2021, 01:29:22 pm
I think l would rather have a clogged paper filter than a reusable that could suck dust into engine accelerating top end wear.


viczena

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Reply #26 on: April 08, 2021, 01:47:24 pm
i understand that you do prefer engines that do not work.
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Fred Gassit

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Reply #27 on: April 08, 2021, 02:21:55 pm
The test we are interested in is:
"ISO 5011:2020(en)
Inlet air cleaning equipment for internal combustion engines and compressors — Performance testing"

It's very difficult to find results pertaining to actual particle size that the various different filter constructions will capture, but here is one test (for a diesel truck rather than a motorcycle, but the test methodology is the same):



"Filtering efficiency is a measure of the filter’s overall ability to capture dirt."
" The course test dust has a specific distribution of particle sizes ranging from less than 2.5 microns to greater than 80 microns."

So, 99.93% efficient for an off-the-shelf AC Delco paper filter, and a pretty poor 96.8% for the K&N. That's a lot of crud getting through.

And a thought provoking personal opinion from master mechanic Shawn Smoak (jump to 2m30s):
TheSmoaksVlogs


viczena

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Reply #28 on: April 08, 2021, 02:26:32 pm
With filters you always have to make a compromise. If you have a very efficient filter, less air comes through and it clogs up easily. Until nothing goes through. If you have a filter with less efficiency, more air goes through and the filter keeps open longer.

You can enlarge the surface of the filter, but you get to physical limits.

The difference between the best and the K&N filter is mere 3%.

The guy in the video never seems to have opened an engine. And inspected if this "grind" did some damage at all.

BTW: The efficiency is only one oft the test in ISO 5011. The others are equally important. And I have an idea which filter is the winner in the other categories. And there are even 3 different efficiencies in ISO 5011. Which one the graph shows keeps unclear. Most probably the initial efficiency. Determined after the addition of 20 g of contaminant or the number of grams numerically
equivalent to 6 times the air flow in cubic metres per minute, whichever is the greater.
« Last Edit: April 08, 2021, 02:45:15 pm by viczena »
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biscot

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Reply #29 on: April 08, 2021, 04:22:00 pm
I'm a bit confused - I have the DNA filter (and removed the snorkel in favor of the open filter with the DNA cover plate or whatever you call it).
Is this the same as the K&N filter? I don't care about the sound, or the supposed performance upgrade, I just want to know I'm giving my engine the optimum intake protection. I do ride on duscty roads, and clean and re-oil the filter at intervals. Would I be better off to go back to paper filters and just change them on intervals? It's not about saving a few bucks, just preventing premature engine damage.
Sorry if this is taking the thread off topic.


BlackIce619

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Reply #30 on: April 08, 2021, 04:28:34 pm
I'm a bit confused - I have the DNA filter (and removed the snorkel in favor of the open filter with the DNA cover plate or whatever you call it).
Is this the same as the K&N filter? I don't care about the sound, or the supposed performance upgrade, I just want to know I'm giving my engine the optimum intake protection. I do ride on duscty roads, and clean and re-oil the filter at intervals. Would I be better off to go back to paper filters and just change them on intervals? It's not about saving a few bucks, just preventing premature engine damage.
Sorry if this is taking the thread off topic.

As mentioned before. It is always a balance between allowing the engine to breathe a little more (Performance), or restricting it through a more thorough filtering process. I dont believe anything will ever exist where you can have perfect breathing engine and 100% particle filtration. In essence you would have to have a hospital-type HVAC system inside your motorcycle  :o.

If you truly do not care about performance and you want to filter out 3% more, then keep stock filter. If you want to let your engine breathe a bit more, increasing performance and MPG, then leave the DNA filter and enjoy life!
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Jack Straw

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Reply #31 on: April 08, 2021, 04:34:44 pm
Gosh, I wonder what the best oil for the filter could be?
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biscot

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Reply #32 on: April 08, 2021, 04:43:08 pm
Gee, sorry if I opened a can of worms. Maybe there's no true answer. I'll meditate on it and go back to worrying about oil filters.


BlackIce619

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Reply #33 on: April 08, 2021, 04:43:27 pm
Gosh, I wonder what the best oil for the filter could be?

Just use the same engine oil so that EVERYTHING stays lubed.



P.S. That is a joke everyone. Please do not that that comment serious. ::)
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Jack Straw

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Reply #34 on: April 08, 2021, 05:09:47 pm
Hey BlackIce,

It's a good idea there, to insert a "humor disclaimer".

Air filters, oil filters, oil for ANY application, and......SUSPENSION!!!!!!!!  get some of us really worked up.  Here's a totally unsolicited tip from a geezer;  don't EVER tell anyone what oil you use. It'll drive some guys nuts but it's good to rise above the fray.



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biscot

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Reply #35 on: April 08, 2021, 05:11:00 pm
 :D :D


NVDucati

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Reply #36 on: April 08, 2021, 05:12:21 pm
So, this is the problem as i see it: once the oiled-cotton filter gets dirty enough that all the oil dries out, it’s possible for dusty air to make its way through the more porous filter media and into your engine, whereas a paper filter with it's much smaller voids would simply become blocked.

Am I missing something?
You are certainly asking the correct and smart questions.
   It helps to consider a couple of differences. How are cotton and paper made? The cotton media is woven, the paper media is soaked and pressed flat. Then consider the difference between air and dirt. Air molecules are obviously much smaller and, in turn, much more "fluid"(fluidity). The air can weave its way through either material better than can dirt.
   Next consider the construction. When you grab a woven cotton filter, like K&N, you will notice the stainless steel screen on both the inside and outside of the cotton. That allows the material to be thicker and hold the pleats which are also deeper, providing more surface area (that also adds to the expense). Picture the dirty air having to race through a slalom course. The air molecules win. Then it is a mater of scale. The distinction is fluidity not porosity.
  Staying on the subject of construction for a moment longer, notice the difference between soft wider rubber gaskets compared to hard narrow plastic. Then picture micro-pounding(bouncing) from vibration those gaskets experience while trying to maintain the "coastline" seal against dirt particles.
   Back to one part of your specific question, "...whereas a paper filter with it's much smaller voids would simply become blocked." Actually that would be nice buy way, way before a paper filter gets literally blocked the suction of the intake will simply pull the dirt particles through the material. You might notice a bit of slower starting but it will still run.
   In the end both types have a finite duty cycle. The dirty air we ride through is the same for both.
 
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GravyDavy

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Reply #37 on: April 08, 2021, 09:17:15 pm
No worries GravyDavy. I was reacting to your question “Does anybody know if they are publishing the micron rating of a new, properly oiled one?” when I had just, minutes before, posted links to specific, independent information.

I truly get it that none of this might matter, at all, to some folks. But I guess I could have also mentioned that the FAA has certified K&N filtration for aircraft. One supplier cites:
“K&N re-cleanable air filter media
Up to 50% more air flow with the same dirt holding capability
NO ADS (Airworthiness Directive) 
Increased horsepower
Reported fuel savings of .3 to .5 gallons per hour”

A third to a half gallon saved per hour is a big deal for pilots. Not so much as a money saver but for the effect on available range. (from 6000ft you can’t just push your plane to the next gas station) Even if one only looks at it from an ecological viewpoint including the notion of the disposables… it is not just a drag strip thing. Don’t know if that matters.
   Last, how often one changes a air filter is subject to a lot of considerations. One consideration should be that as any air filter gets covered with dust, it creates a vacuum on the fuel intake side. Paper filters are more prone to eventually suck the particles right on through much sooner.

Thanks.  Being lazy, I rarely click on links.  It does sound like a K&N could be a worthwhile choice, and that if there ever were any problems, they've made changes to fix them.


Hoiho

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Reply #38 on: April 09, 2021, 12:32:30 am
You are certainly asking the correct and smart questions.
   It helps to consider a couple of differences. How are cotton and paper made? The cotton media is woven, the paper media is soaked and pressed flat. Then consider the difference between air and dirt. Air molecules are obviously much smaller and, in turn, much more "fluid"(fluidity). The air can weave its way through either material better than can dirt.
   Next consider the construction. When you grab a woven cotton filter, like K&N, you will notice the stainless steel screen on both the inside and outside of the cotton. That allows the material to be thicker and hold the pleats which are also deeper, providing more surface area (that also adds to the expense). Picture the dirty air having to race through a slalom course. The air molecules win. Then it is a mater of scale. The distinction is fluidity not porosity.
  Staying on the subject of construction for a moment longer, notice the difference between soft wider rubber gaskets compared to hard narrow plastic. Then picture micro-pounding(bouncing) from vibration those gaskets experience while trying to maintain the "coastline" seal against dirt particles.
   Back to one part of your specific question, "...whereas a paper filter with it's much smaller voids would simply become blocked." Actually that would be nice buy way, way before a paper filter gets literally blocked the suction of the intake will simply pull the dirt particles through the material. You might notice a bit of slower starting but it will still run.
   In the end both types have a finite duty cycle. The dirty air we ride through is the same for both.

Thanks NV, always appreciate your input.


GravyDavy

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Reply #39 on: April 09, 2021, 12:58:11 am
Just my opinion, but it seems to me that for the great majority of riders the only significant differences between the stock setup and the snorkel delete + gauze filter are:

Noise level

Wallet weight

And whether to clean&re-oil or replace the filter element.

Unless the stock paper element is truly dismally restrictive, there will be no perceptible performance difference, except maybe at WFO bouncing off the rev limiter. I would bet that the snorkel removal accounts for virtually all of the perceived performance change, and most of that is the "it's louder so it must be faster" assumption.

The stock paper filter has abundant surface area and net free area.  Lots of V8 hotrods with 4-barrel carbs have worked quite adequately with shorty filters using much less filtration material. A gauze filter may flow even better, but more than enough doesn't add any performance. If my assumptions and reasoning are correct, the choice to use a gauze filter mostly boils down to reusability. And that can be a good reason.

Let the flames begin.


Jack Straw

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Reply #40 on: April 09, 2021, 01:05:02 am
+1 on that.   This is sort of a classic forum mini tempest in a tea pot.  Is the darned filter reasonably clean??  If not, replace or clean it and go ride the bike.  Stop fretting over this small stuff.

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drums4money

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Reply #41 on: April 09, 2021, 01:52:53 am
Gosh, I wonder what the best oil for the filter could be?

Marvel's Mystery Oil guarantees 5 more hp. 
hypocrite, four flusher, snake in the grass, just a swindler and wolf in sheep's clothing. . . . liar.


gizzo

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Reply #42 on: April 09, 2021, 02:26:42 am
Just my opinion, but it seems to me that for the great majority of riders the only significant differences between the stock setup and the snorkel delete + gauze filter are:

Noise level

Wallet weight

And whether to clean&re-oil or replace the filter element.

Unless the stock paper element is truly dismally restrictive, there will be no perceptible performance difference, except maybe at WFO bouncing off the rev limiter. I would bet that the snorkel removal accounts for virtually all of the perceived performance change, and most of that is the "it's louder so it must be faster" assumption.

The stock paper filter has abundant surface area and net free area.  Lots of V8 hotrods with 4-barrel carbs have worked quite adequately with shorty filters using much less filtration material. A gauze filter may flow even better, but more than enough doesn't add any performance. If my assumptions and reasoning are correct, the choice to use a gauze filter mostly boils down to reusability. And that can be a good reason.

Let the flames begin.
+1.
That's what I was trying to get at, in less words.
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zimmemr

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Reply #43 on: April 09, 2021, 02:19:54 pm
+1 on that.   This is sort of a classic forum mini tempest in a tea pot.  Is the darned filter reasonably clean??  If not, replace or clean it and go ride the bike.  Stop fretting over this small stuff.

As usual Jack, you've summed it up nicely. 


viczena

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Reply #44 on: April 09, 2021, 02:26:16 pm
When paper and gauze filters are both new, no filter wins. But the gauze keeps the airstream open much longer. Paper detoriates quite fast.
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Reply #45 on: April 09, 2021, 02:32:46 pm
Sticking with my newly cleaned and re-oiled DNA aka S&S aka K&N (with the best oil, of course). Going for a ride. Still have the original OEM filter in case I change my mind.  :D


gizzo

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Reply #46 on: April 15, 2021, 03:53:26 am
Here's why I don't rate reusable air filters: this is a pic of the inside of the clean air side of the filter box from my daughter's WRX. It's a bit hard to make out but if you look carefully you might be able to see dirt coating many of the surfaces. This car has a K&N flat panel element. I know it was serviced properly because I did it myself, 5000km ago. Not a fan. I'm replacing it for her with a pleated paper filter. They filter well in our dusty conditions and fit properly. A motorbike in Europe probably has quite different filtering needs.

Shout out to @viczena, your input is not required at this time. I'm a qualified heavy diesel mechanic, I know what I'm doing and I have experience with these things. Please keep your opinion to yourself. Thank you.
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Hoiho

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Reply #47 on: April 15, 2021, 05:45:18 am
Holy crap, that's not great...


viczena

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Reply #48 on: April 15, 2021, 08:41:10 am
Yep, maybe we have a quite different filtering need. In WW2 the air filters of the BMW/Zündapp sidecars had a filter that was not sufficient for russia. So the developed an oil bath air filter. That was sufficient.

So there are conditions where a K&N might not be sufficient. Then take a paper filter and change more often. And if you get into more severe conditions, a paper filter might not be good enough and you need special filtration systems.

the yellow stuff looks like something organic. And it looks like the old filter did not fit properly. As you suggested. I once had a K&N for a 3.0 Ducato. It did not really fit well, therefore I changed back to paper.

So whatever you do, dont install an air filter that does not fit snuggly. Even if it is a paper filter.
« Last Edit: April 15, 2021, 09:23:42 am by viczena »
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gizzo

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Reply #49 on: April 15, 2021, 12:09:04 pm
Holy crap, that's not great...

Not really, huh? At least the bees and wasps stayed on the other side.....
simon from south Australia
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BlackIce619

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Reply #50 on: April 15, 2021, 05:02:39 pm
Posting this comment here, as I posted it in another thread and it's more appropriate here. See below.
________________________________

I am just going to leave this here for those interested. Found it applicable to our conversation.

https://www.youtube.com/watch?v=GS69owXpGdY

Another channel I follow with good information....

https://www.youtube.com/watch?v=sJ3L-E-ufYo
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zimmemr

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Reply #51 on: April 15, 2021, 05:38:30 pm
Not really, huh? At least the bees and wasps stayed on the other side.....
Hey Gizzo, as a fellow old diesel wrangler how many times have you opened the hood on some old crock that sat in a field between jobs and found mud wasps had built or yellow jackets had built a condo in the thing? ;D

I once had to rush one of my guys to the emergency room after he opened the access panel on a JD compressor that had been sitting behind the shop and got a face full of the bastards for his trouble.


6504me

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Reply #52 on: April 15, 2021, 06:25:20 pm
In my experience thee trick to using K&Ns successfully is whether the seal actually seals, not using compressed air to dry them out when cleaning, and using the correct oil in the CORRECT amount and not over oiling.

I have seen K&N installations where the seal just does not seal and a liberal application of basic (coarse) wheel bearing grease solves the problem.


GravyDavy

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Reply #53 on: April 16, 2021, 01:03:11 am
Or just use a stock filter that is designed so any yahoo can install it adequately without greasing poorly manufactures seals and hoping/assuming that some other yahoo has never used compressed air before improperly oiling the ruined gauze. Needing to know the "trick" to make something work is a sure sign of a product that won't work for Joe Average.

If gauze filters were unequivocally better, they would be installed at the factory because they would reduce expensive warranty claims.  They only make sense in a rigidly controlled precision maintenance environment.


6504me

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Reply #54 on: April 16, 2021, 01:08:24 am
Or just use a stock filter that is designed so any yahoo can install it adequately without greasing poorly manufactures seals and hoping/assuming that some other yahoo has never used compressed air before improperly oiling the ruined gauze. Needing to know the "trick" to make something work is a sure sign of a product that won't work for Joe Average.

If gauze filters were unequivocally better, they would be installed at the factory because they would reduce expensive warranty claims.  They only make sense in a rigidly controlled precision maintenance environment.

"Or just use a stock filter..." and keep buying them $20 time after $20 time after $20 time after$20 time after $20 time after $20 time just like the manufacturer wants you to or a K&N for $50 once.

If they can figure a way to get around the patent and gauze filters are more expensive to manufacture than paper filters.


gizzo

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Reply #55 on: April 16, 2021, 01:37:52 am
Or just use a stock filter that is designed so any yahoo can install it adequately without greasing poorly manufactures seals and hoping/assuming that some other yahoo has never used compressed air before improperly oiling the ruined gauze. Needing to know the "trick" to make something work is a sure sign of a product that won't work for Joe Average.

If gauze filters were unequivocally better, they would be installed at the factory because they would reduce expensive warranty claims.  They only make sense in a rigidly controlled precision maintenance environment.

Yep. Remove the paper element from a car airbox and see if you can tell the difference. I doubt it.
"Or just use a stock filter..." and keep buying them $20 time after $20 time after $20 time after$20 time after $20 time after $20 time just like the manufacturer wants you to or a K&N for $50 once.

The service kit isn't free and it's time consuming to service a K&N properly. Then you need to waste more time making it fit. I'm with @gravydavy, if you can't just slide it in and make it work, it's not ideal. The money thing, whoopy do. $20. I spend more than that on fuel on a day ride. Changing the filter every couple of years isn't going to break me.

But, to each their own. Swings and roundabouts and all that and if it makes you happy, why not.
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