High Flow Air Filters

[FloridaJim5]

Does anyone have real world experiences on how a State 1 K&N Filter affects engine wear or longevity? 
Maybe the engine builders here can explain or review their findings after an engine experiences 30,40 or 50,000 miles with a K&N filter. 

Is there more or accelerated engine wear? 
Do you notice scoring in the cylinders? 
Are top end overhauls necessary more often?
Oil consumption?   

I live in Central Florida (Orlando so not close to the beach) and it is very sandy here.  Sand just seams to fly around in the air. Looking under the hood of my truck, there are little puddles of sand everywhere under the hood and the it's the same with my Ultra. Maybe the K&N is good with general dust and dirt, but I'm concerned that it may not be able to filter out the sand. I typically ride 6 to 8,000 miles per year and I think my current 2019 Ultra is my last Harley and I want it to last as long as possible.

Most internet searches are filled with anecdotal opinions and not facts. It seems to be spilt 50/50....it's the best thing since sliced bread or they are junk. They range from "My car has been using it or 200,000 miles and doesn't burn a drop of oil" to "Don't ever ever use one because it will ruin your engine". I couldn't find many Harley opinions or anything in the HTT search function. 

Thank you!   

[Hossamania]

All I can tell you is that I've run one for 20 years and 125,000 miles, it sure seemed to run fine this weekend. It is the one that gets oiled. The bike uses no more oil than it ever has.
Not factual, just anecdotal.

[FloridaJim5]

All I can tell you is that I've run one for 20 years and 125,000 miles, it sure seemed to run fine this weekend. It is the one that gets oiled. The bike uses no more oil than it ever has.
Not factual, just anecdotal.

Well Hoss, your opinion means a lot. I think its ability to filter is dependent on how it's cleaned and oiled on a regular basis.     

[Buglet]

  I was told by a K&N rep not to clean the filter often, he said they filter the air better when they have some dirt on them. I was also told by Dodge they would void your warranty if you ran one on there diesels. The ones I ran never had any problems.

[Ohio HD]

Does anyone have real world experiences on how a State 1 K&N Filter affects engine wear or longevity? 
Maybe the engine builders here can explain or review their findings after an engine experiences 30,40 or 50,000 miles with a K&N filter. 

Is there more or accelerated engine wear? 
Do you notice scoring in the cylinders? 
Are top end overhauls necessary more often?
Oil consumption?   

I live in Central Florida (Orlando so not close to the beach) and it is very sandy here.  Sand just seams to fly around in the air. Looking under the hood of my truck, there are little puddles of sand everywhere under the hood and the it's the same with my Ultra. Maybe the K&N is good with general dust and dirt, but I'm concerned that it may not be able to filter out the sand. I typically ride 6 to 8,000 miles per year and I think my current 2019 Ultra is my last Harley and I want it to last as long as possible.

Most internet searches are filled with anecdotal opinions and not facts. It seems to be spilt 50/50....it's the best thing since sliced bread or they are junk. They range from "My car has been using it or 200,000 miles and doesn't burn a drop of oil" to "Don't ever ever use one because it will ruin your engine". I couldn't find many Harley opinions or anything in the HTT search function. 

Thank you!   

Take two given air filters, both same size, both the same application (exact same bikes), one flows considerably better than the other. The one that allows more air through the same area will let small dirt particles through easier than the other. That's why they oil the gauze filters. In hope of attracting some of the dirt particles.
 

[Hossamania]

I was told by a K&N rep not to clean the filter often, he said they filter the air better when they have some dirt on them. I was also told by Dodge they would void your warranty if you ran one on there diesels. The ones I ran never had any problems.

I had also heard that about not cleaning them often. Took it to heart and sometimes think I don't clean it often enough, easily a year on it between cleanings, maybe two sometimes, 6-12 thousand miles. Maybe more? I'm not a record keeper. (Oil either, for a different thread.)

[FloridaJim5]

Ohio:  That makes common sense and that's the part that bothers me.  However, in my research and supposedly from a K&N rep, the magic of the filter is how if filters the air while the engine is running.  K&N says that the engine pulses cause the individual fibers in the cotton gauze to vibrate very rapidly which creates filtering just as good as a paper filter, but it still has the same flow characteristics while running.  Is this true?  No idea, but it sounds good or maybe it's just typical company sales claims. 

That's why I was hoping to hear from an engine builder that can either back up K&N's claims or not. 

Hoss:  Plenty of claims out there also such as yours.  The dirt it traps seems to be evidence of how well it captures dirt and debris.  Maybe? I don't know.  Or maybe you need to clean yours more often.

[kd]

Hoss's filter gets dirty because he has trouble keeping up. It gets dusty back there. 

[Ohio HD]

Ohio:  That makes common sense and that's the part that bothers me.  However, in my research and supposedly from a K&N rep, the magic of the filter is how if filters the air while the engine is running.  K&N says that the engine pulses cause the individual fibers in the cotton gauze to vibrate very rapidly which creates filtering just as good as a paper filter, but it still has the same flow characteristics while running.  Is this true?  No idea, but it sounds good or maybe it's just typical company sales claims. 

That's why I was hoping to hear from an engine builder that can either back up K&N's claims or not. 

Hoss:  Plenty of claims out there also such as yours.  The dirt it traps seems to be evidence of how well it captures dirt and debris.  Maybe? I don't know.  Or maybe you need to clean yours more often.

I doubt that anyone has that type of information as it would have to be an intentional study to really know. Is a higher flow are filter detrimental to the motor? I doubt it would be significant, unless you ride in dust or gritty areas.
 

[fbn ent]

Hoss's filter gets dirty because he has trouble keeping up. It gets dusty back there. 

   He'd stay ahead on a RG....

[kd]

True. I figured that went without sayin. 

[kd]

Ohio:  That makes common sense and that's the part that bothers me.  However, in my research and supposedly from a K&N rep, the magic of the filter is how if filters the air while the engine is running.  K&N says that the engine pulses cause the individual fibers in the cotton gauze to vibrate very rapidly which creates filtering just as good as a paper filter, but it still has the same flow characteristics while running.  Is this true?  No idea, but it sounds good or maybe it's just typical company sales claims. 

That's why I was hoping to hear from an engine builder that can either back up K&N's claims or not. 

Hoss:  Plenty of claims out there also such as yours.  The dirt it traps seems to be evidence of how well it captures dirt and debris.  Maybe? I don't know.  Or maybe you need to clean yours more often.

I doubt that anyone has that type of information as it would have to be an intentional study to really know. Is a higher flow are filter detrimental to the motor? I doubt it would be significant, unless you ride in dust or gritty areas.
 

Green Filters has a machine that measures atmospheric pressure changes through filters in several manufacturers and states of service.  I figured Oh yeah, this should be fairly hokey.  I spent some time watching it work and figured it was pretty cool.  I definitely saw the difference between popular and OEM brands compared to theirs and was surprised how well theirs performed as a filter with uninterrupted flow.  I believe the machine is in the link I provided earlier.

[Ohio HD]

Ohio:  That makes common sense and that's the part that bothers me.  However, in my research and supposedly from a K&N rep, the magic of the filter is how if filters the air while the engine is running.  K&N says that the engine pulses cause the individual fibers in the cotton gauze to vibrate very rapidly which creates filtering just as good as a paper filter, but it still has the same flow characteristics while running.  Is this true?  No idea, but it sounds good or maybe it's just typical company sales claims. 

That's why I was hoping to hear from an engine builder that can either back up K&N's claims or not. 

Hoss:  Plenty of claims out there also such as yours.  The dirt it traps seems to be evidence of how well it captures dirt and debris.  Maybe? I don't know.  Or maybe you need to clean yours more often.

I doubt that anyone has that type of information as it would have to be an intentional study to really know. Is a higher flow are filter detrimental to the motor? I doubt it would be significant, unless you ride in dust or gritty areas.
 

Green Filters has a machine that measures atmospheric pressure changes through filters in several manufacturers and states of service.  I figured Oh yeah, this should be fairly hokey.  I spent some time watching it work and figured it was pretty cool.  I definitely saw the difference between popular and OEM brands compared to theirs and was surprised how well theirs performed as a filter with uninterrupted flow.  I believe the machine is in the link I provided earlier.

As well K&N no doubt has similar testing equipment. But neither can predict the outcome of 100,000 miles on an HD motor under poor road conditions. That's what I was speaking to. That would take an intentional real life study.

[itsafatboy]

not sure if around anymore but E-xotic made a 2 5/8" tapered, stainless surgical mesh so 35 micron or so, i use one but cant seem to find any longer no oil , I do think Arlen ness makes a stainless one now but not sure what sizes , i like it because the filter is constant size filtration and flows great,  and when i clean i see no dirt or oil in throttle body , i also vent external

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[kd]

Ohio:  That makes common sense and that's the part that bothers me.  However, in my research and supposedly from a K&N rep, the magic of the filter is how if filters the air while the engine is running.  K&N says that the engine pulses cause the individual fibers in the cotton gauze to vibrate very rapidly which creates filtering just as good as a paper filter, but it still has the same flow characteristics while running.  Is this true?  No idea, but it sounds good or maybe it's just typical company sales claims. 

That's why I was hoping to hear from an engine builder that can either back up K&N's claims or not. 

Hoss:  Plenty of claims out there also such as yours.  The dirt it traps seems to be evidence of how well it captures dirt and debris.  Maybe? I don't know.  Or maybe you need to clean yours more often.

I doubt that anyone has that type of information as it would have to be an intentional study to really know. Is a higher flow are filter detrimental to the motor? I doubt it would be significant, unless you ride in dust or gritty areas.
 

Green Filters has a machine that measures atmospheric pressure changes through filters in several manufacturers and states of service.  I figured Oh yeah, this should be fairly hokey.  I spent some time watching it work and figured it was pretty cool.  I definitely saw the difference between popular and OEM brands compared to theirs and was surprised how well theirs performed as a filter with uninterrupted flow.  I believe the machine is in the link I provided earlier.

As well K&N no doubt has similar testing equipment. But neither can predict the outcome of 100,000 miles on an HD motor under poor road conditions. That's what I was speaking to. That would take an intentional real life study.

Under controlled conditions with known micron contaminate at measured and equal CFM.  Yeah, we can do that.    Yeah, I'm sure they all have machines to sell their wares.  I watched the comparisons using the brick style auto filters for a while at SEMA.  I looked for a bleeder valve or some other gadget.  The one thing I liked about them other than how the numbers looked is they claimed they could custom build a filter element for any dimension with their stock of end and base rubber molds.  I started to build a breather with a bellmouth stack in it and have yet to get back to it. 

[Hossamania]

Hoss's filter gets dirty because he has trouble keeping up. It gets dusty back there. 

Ouch.

Hoss's filter gets dirty because he has trouble keeping up. It gets dusty back there. 

   He'd stay ahead on a RG....

Ouch!

[tdrglide]

As far as I can tell, the E-xotic filters are no longer available. Too bad, as I'd like to find another one. I've cleaned the one I have several times. Last couple times I lightly oiled it with K&N. Catches dirt

[jmorton10]

I've run K&N filters for as long as I can remember (I've been riding since the late 60's).  I used to worry about the K&N letting in too much fine s*** but I don't worry about it anymore.

Heck, in the late 60's I ran a Panhead with a velocity stack for two years. Now I don't ride my bikes for 200,000 miles like a couple guys I know but I did ride the Pan from upstate NY to Sturgis & back (rigid frame/AEE springer with no frt brake lol).

In all my years riding/wrenching etc. I can't really point to any engine problem or failure where I said "damn, I should have been running a better air filter" !!

~John

[mkd]

I have ran K&N filters on three bikes, two carbureted and one fuel injected without issue. I also have a K&N filter in my 2009 GMC sierra 5.3 since it was new, it now has 84,000 miles . The truck engine had a problem with the mass air flow sensor in the air tube between the air filter and the throttle body. The engine at around 60,000 miles started to idle ruff and actually stalled after it was warmed up. The sensor looks like filament in a tail light bulb and it must be absolutely clean for it to work correctly. Bought a can of mass air flow sensor cleaner and took the sensor out and sprayed the filament off without touching it and problem solved. I believe the oil from the K&N filter after 60,000 miles caused the filament to attract dirt/dust particles which caused the ecm to distribute fuel incorrectly. now i periodically remove and clean the sensor every other oil change or so. Youtube was my friend in finding and curing the issue.

[bobrk1]

Does anyone have real world experiences on how a State 1 K&N Filter affects engine wear or longevity? 
Maybe the engine builders here can explain or review their findings after an engine experiences 30,40 or 50,000 miles with a K&N filter. 

Is there more or accelerated engine wear? 
Do you notice scoring in the cylinders? 
Are top end overhauls necessary more often?
Oil consumption?   

I live in Central Florida (Orlando so not close to the beach) and it is very sandy here.  Sand just seams to fly around in the air. Looking under the hood of my truck, there are little puddles of sand everywhere under the hood and the it's the same with my Ultra. Maybe the K&N is good with general dust and dirt, but I'm concerned that it may not be able to filter out the sand. I typically ride 6 to 8,000 miles per year and I think my current 2019 Ultra is my last Harley and I want it to last as long as possible.

Most internet searches are filled with anecdotal opinions and not facts. It seems to be spilt 50/50....it's the best thing since sliced bread or they are junk. They range from "My car has been using it or 200,000 miles and doesn't burn a drop of oil" to "Don't ever ever use one because it will ruin your engine". I couldn't find many Harley opinions or anything in the HTT search function. 

Thank you!   

using  them for  probably  25 years , I  live  on  a  dirt road  and  just  cleaned  it ,no problem .

[cbumdumb]

not sure if around anymore but E-xotic made a 2 5/8" tapered, stainless surgical mesh so 35 micron or so, i use one but cant seem to find any longer no oil , I do think Arlen ness makes a stainless one now but not sure what sizes , i like it because the filter is constant size filtration and flows great,  and when i clean i see no dirt or oil in throttle body , i also vent external

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Check out fuel moto website they announced yesturday that they started handling a line of stainless air filters they may have the size and shape you need.

[FloridaJim5]

This pic is the top of the air box on my 2021 Hemi Ram 1500.I really appreciate the experience of the posts that mention how many miles or years a K&N has been used, but this pic is why I'm asking about the ability of the K&N to filter sand.  I live in the Orlando area and rarely go anywhere near the beach, but sand is obviously in the air.  It puddles everywhere under the hood of my truck and it's only driven on city streets and expressways in the area.   

Will a K&N filter Sand?  It's obviously flying around in the air and my Ultra has the same puddles of sand after ridden only a few miles after a wash. 

[fbn ent]

Should be fine...

[dieselbeef]

we race quads here in fl...we use the kn style filters with an outerware...see no real issues with sand getting into th intake or into the cyl..weve been usug them for many yrs and havent ever had a failure due to dirt ntrusion..no accelerated wear or even finding any in the intake......we are constantly n dust clouds....i also run one on my breakout and all my trucks

[Deye76]

FloridaJim5, try a rain sock? Might keep some of the sand out.

[FloridaJim5]

Thanks guys.  I'm becoming more comfortable with the filter based on the comments in this thread. 

I want this engine to last as long as possible since I'm pretty sure it's my forever Harley. 

[smoserx1]

I put a K&N on my old 99 way back when it had about 80000 miles on it.  Now the bike has 229000.  I did do a top end and made it into a 95 at 179000 and reused the same filter.  Other than the cylinders being worn out from high mileage I saw no obvious signs of damage I would contribute to poor filtration. I know this is not  scientific.  I clean my filter very seldom.  I worked in the air pollution industry my entire career and learned very early that any filter works better with a particulate layer on it. Engineers measure filtration efficiency in microns....that is a millionth of a meter, and 80 microns are roughly the thickness of a human hair.  I cannot imagine sand going through that filter.

[FloridaJim5]

I put a K&N on my old 99 way back when it had about 80000 miles on it.  Now the bike has 229000.  I did do a top end and made it into a 95 at 179000 and reused the same filter.  Other than the cylinders being worn out from high mileage I saw no obvious signs of damage I would contribute to poor filtration. I know this is not  scientific.  I clean my filter very seldom.  I worked in the air pollution industry my entire career and learned very early that any filter works better with a particulate layer on it. Engineers measure filtration efficiency in microns....that is a millionth of a meter, and 80 microns are roughly the thickness of a human hair.  I cannot imagine sand going through that filter.

Thanks for your comment. I appreciate your experience. 

Do you know the micron filtration size of the K&N?  What size in microns is a grain of sand?

[smoserx1]

https://www.engineeringtoolbox.com/particle-sizes-d_934.html

No, I don't know the K&N rating.