K&N

[Dogsled]

Is there a lifespan anyone knows about for the K&N air filter. I have the K&N cleaning kit and all it says is it cleans over and over. Mine has no holes or wear I can see, but I have alot of over and overs on it! You would think at some point, age on the material itself would cause air flow restrictions. I've run this at least ten years, anybody run one longer with no issues. My bike runs good, just curious.

[Viking]

I had one on my bike for over 20 years. Just wash, dry and reoil from time to time. Finally had to replace it when I broke my side stand, and leaned the bike against a pole and the filter got flattened, so it did not fit anymore. They aren't real good at fine level filtration, but they last a real long time.

[Fatwing Chris]

So lasting a long time trumps good filtration?

[WingAdmin]

So lasting a long time trumps good filtration?

Not in my books.

[Dogsled]

I know K&N is a quality product but everything has a usage life. I'm curious as to Vikings statement about filtration or I would assume micron levels of filtration of K&N and makes me wonder how OEM compares. I've never had any problems up til now but would like to know exactly what i'm using here.

[Viking]

K&N filtration levels are dependent on how much oil you put in the filter, and how much dirt has closed the pores up. More oil, better dirt catching, but too much oil and it traps too much dirt and becomes almost impervious to air very quickly. Also, when the filter gets a bit dirty, it then begins to filter to a smaller micron level, but when it is clean, it probably does not remove better than 25+ microns. Now before anyone gets their panties in a knot and asks if I have any studies or charts that prove all this - google it. OEM filters are as good at filtration as K&N are. When they get dirty, you throw them away and get new ones. Air filters by their very nature are not too efficient either at the brand new end or at the dirty end, but they all take the majority of dirt out of the equation and slow down how much goes into your engine. It is a tossup on air flow versus filtration. There are so many studies and reports on this that it is impossible to read them all in a single lifetime. K&N for certain applications (or maybe all), make a filter that stands up to more punishment, and at some point in their cycle, they filter down as small as possibly 10 microns. That is why I use them for Harleys - because they are stuck out there where they can get banged and bumped. In my Goldwing, where the filter is submerged so deep in the innards that nothing can harm it except dust and dirt, I would not use a K&N. The foregoing is both my opinion, and my experience. Others may vary.

As far as filtration trumping resilience or vice versa - no filter will take ALL the dirt out, or you would not get any air either. Put an air filter on it - any type - your choice. The differences are minimal.

[Fatwing Chris]

So you throw in a K&N which filtering abilities are scetchy(have to be partialy plugged to work good)and then you take a chance on over or under oiling making it that much more scetchy?Unless you like the extra intake noise I can't get my head around taking a chance on using one for the little bit of difference(if any)in performance or money savings.
Might be considered apples and oranges,but over on the atv sites the local engine builders love K&N.It keeps them in business.JMHO.

[Dogsled]

I never had any problems with the K&N, was just wondering just wondering about overall life. My issue was the life of the element material itself.
I will keep it in mind if I go off-roading on my Wing. I'm sure ATVer's have different needs.

Good explanation Viking. I clean it in the spring and never noticed it being real dirty. A quick clean and a light fan of oil and I stick it back in. I'll give it a closer inspection this spring Thanks for everybody's opinion.

[ct1500]

My take on these filter claims of more air flow are ridiculous for the average street rider/tourer riding his machine at 3500 RPM. The OEM filter when designed by the manufacturer I would bet dollars to donuts flows sufficiently for its intended purpose all the way up to its redline or WOT without any restriction. Why would a manufacturer purposefully limit air flow?

For the sake of argument lets say an engine at WOT uses 50 cubic feet or air per minute and at 3500 RPM uses 25. How in the world are you going to make that engine use more air with a so called less restrictive filter when running at cruise speed, it only uses the amount of air called for at a given RPM.

Large trucks have filter minders using vacuum readings to tell the driver/mechanic when to replace and filter starts getting plugged/restricted. I would like to see an after market test of new filters and comparison using vacuum or water column readings under filter to substantiate their claims and until that time will stick with OEM designed products. Extra intake noise does not automatically equate to extra power.

[Fatwing Chris]

I never had any problems with the K&N, was just wondering just wondering about overall life. My issue was the life of the element material itself.
I will keep it in mind if I go off-roading on my Wing. I'm sure ATVer's have different needs.

Good explanation Viking. I clean it in the spring and never noticed it being real dirty. A quick clean and a light fan of oil and I stick it back in. I'll give it a closer inspection this spring Thanks for everybody's opinion.

Wing,atv,lawn tracter,whatever it needs to actually filter properly the minute you put it in and not after it's half plugged.Clean your filter and then hold it up to the sunlight and take a look at how many specks of light you can see through it.While it's out run your finger in around the inside of the throttle bodies and see how much crap is on your finger.Or not,I could really care less as it's your bike.

[Dogsled]

Now fatWing, that's the best test i've heard yet. A white cotton wipe as deep as I can on the throttle body to see how clean it is. I will be curious to see what it looks like. Of course my test will be with a K&N as I have nothing else to compare it to. The rubber edge certainly seals it off so whatever is there will have to have come thru the filter. Hopefully someone may try thiswith an OEM to compare.