The summary ...

Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt. See the data tables for a complete summary of these comparisons.

https://www.nicoclub.com/archives/kn-vs-oem-filter.html

Velly interesting !!

 

Test protocol really didn't mimic real-world road usage tho:

 

"The filter is then tested by feeding test dust at a nominal rate of 9.8 grams per minute with a constant airflow of 350 CFM."

Makes no difference. The point being it lets more dirt thru - not exactly good for your engine.

 

Will keep that in mind if my filter is fed 9 grams a minute

@ 350 Ft³ / min.

That is all this is testing.

Like a dirt bike in sand. Maybe.
Nothing can be inferred about typical road use.

Also they did not note if the filter was treated with the oil K&N provides & recommends.

Shoddy science at best.

 

 

I tend to agree with Papa al. The test is unclear of the true conditions and whether or not the K&N filter was properly prepped. While I am not a Pro K&N guy, experiments need to be fairly conducted before statements of do not use a product can be stated.

 

There will always be a trade off, you want more air flow, you sacrifice potential particles getting by. If you want clean air then you constrict flow. 

 

When we Baja raced our Chevy S10, we used K&Ns and never had any issues. 

3 hours ago, canthai55 said:

Makes no difference. The point being it lets more dirt thru - not exactly good for your engine.

 

Sales hype, same I have always thought that said also depends on where you ride and the environment you ride in.

"The reason I started this crusade was that I was seeing people spend a lot of money on aftermarket filters based on the word of a salesperson or based on the misleading, incomplete or outright deceiving information printed on boxes and in sales literature."

Salesperson being the main thing. ????

37 minutes ago, JAFO said:

When we Baja raced our Chevy S10, we used K&Ns and never had any issues.

Not the same.

All filters tested under the same conditions, measured with the same instruments, in a very scientific manner.

"This report shows, with empirical data and sound reasoning, why OEM filters perform better in a variety of areas."

Make of it what you will.

Right. Always believe what 'authorities' say.

Even when their own reports don't support the conclusions.

Wild extrapolations, sketchy methodology,

no problem.

6 hours ago, canthai55 said:

passed 18 times more dirt and captured 37% less dirt.

self contradiction

1 hour ago, Kwasaki said:

Not the same.

How so. Please explain. 

What a load of cr@p.

 

 

And I certainly don't mean the fantastic K+N products. 

 

Fantastic product, and the best bang for buck upgrade on a bike.

 

 

Presuming one doesn't live deep in the Sahara or an apocalyptic nuclear winter. 

I have been using KN filter on my car for 20 years. Originally I was concerned that along with the improved air input there would be abrasive dirt that could cause engine wear. Car now has a huge mileage on it and still does not burn oil, indicating no sign of wear. I should add that I also use expensive synthetic oil for best engine protection.

5 hours ago, canthai55 said:

Makes no difference. The point being it lets more dirt thru - not exactly good for your engine.

 

Go the Thaiway then................done by a Thai mechanic who couldn't afford a new filter. But it seems to filter better than the original. Lol.

23 minutes ago, Happy Grumpy said:

What a load of cr@p.

 

 

And I certainly don't mean the fantastic K+N products. 

 

Fantastic product, and the best bang for buck upgrade on a bike.

 

 

Presuming one doesn't live deep in the Sahara or an apocalyptic nuclear winter. 

We wouldn't have people who ride bikes and cars should we have a "nuclear winter".

2 hours ago, Kwasaki said:

Sales hype, same I have always thought that said also depends on where you ride and the environment you ride in.

"The reason I started this crusade was that I was seeing people spend a lot of money on aftermarket filters based on the word of a salesperson or based on the misleading, incomplete or outright deceiving information printed on boxes and in sales literature."

Salesperson being the main thing. ????

Most of these "Aftermarket" filters from China wouldn't even filter a huge mosquito. 

1 hour ago, JAFO said:

How so. Please explain. 

Racing & road usage not same. 

1 hour ago, Isaanbiker said:

Most of these "Aftermarket" filters from China wouldn't even filter a huge mosquito. 

I know the word I use is offensive but my pa use to say it and say about Chinkie stuff but times change and many of their products are getting up to date with new technology, the oil filter I use and buy in Thailand are Chinese 100 bath each and are just as good as expensive OEM ones.

 

Lifetime air-filters you can clean & re-use IMHO opinion are better I still use gear oil to coat em but there's sticky spay air-filter oil available these days.  

I did some surfing about K&N filters a few years ago when I was considering getting one for my car.

 

A lot of people claimed that they had indeed got better performance and mpg after fitting them.

 

Then I came across a review by a mechanic as to why this was so.

He held up a standard kind of filter and a K&N against a strong light and pointed out that with the K&N you could actually see lots of minute holes whereas with the standard you couldn't.

 

He said that although this would improve the airflow it also allowed more fine particles to pass through into the engine , not good in the long term.

 

This does not express my opinion,only something I found on the internet.

Airflow can be increased by two ways:

 

1. increasing the amount of space that lets air through (the holes) while keeping the surface size of the material the same

2. increasing the surface size of the material. Since you can't just make the filter bigger you could have more folds etc

 

The first case results most likely in less dirt being filtered and more entering the engine unless the hole diameters are kept the same but the amount of holes is increased. Can be tricky to check.

 

The second case can keep the amount of dirt filtered the same but increase airflow. This is pretty simple to check if it actually is the case. Just compare them side by side.

 

 

It is hard for a normal user to judge the airfilters. In any case unless you also tune the rest of the combustion your performance gains will be minimal and you could get a lot more by just simply replacing the stock filter much more often because at least in Thailand my experience is that they clog up very quickly from dust and polution. Heck, I have to clean off black dirt from my helmet after every couple rides. Imagine how much <deleted> an air filter accumulates. Compare how it looks when new and after just one month.

 

PS: I found it interesting how the AC and Baldwin filters have a linear curve while all others have an exponential growth in clogging. The exponential curve makes sense to me

5 hours ago, eisfeld said:

It is hard for a normal user to judge the airfilters. In any case unless you also tune the rest of the combustion your performance gains will be minimal and you could get a lot more by just simply replacing the stock filter much more often because at least in Thailand my experience is that they clog up very quickly from dust and polution. Heck, I have to clean off black dirt from my helmet after every couple rides. Imagine how much <deleted> an air filter accumulates. Compare how it looks when new and after just one month.

This mirrors my own experience. Air filter goes from white to grey very quickly. Altho the inside of the filter medium remains clean. Says a lot for the paper filters efficiency.

Had the car in the shop to fit new F and R dashcams. Guy there with a new Isuzu pickup. Hood open, and I say one of those cone mesh filters had been installed. Holes the size of toothpicks.

Sure looked good tho' 555

 

On 11/3/2019 at 7:42 PM, canthai55 said:

All filters tested under the same conditions, measured with the same instruments, in a very scientific manner.

Doesn't K & N need to be oiled? In which case "the same conditions " might not apply.

Best air filter Imo . But they need to be cleaned and reoiled regular. 

i have used K&N and Pipercross filters on many bikes over 40 years ,, many of my engines have done massive miles even the tuned ones ,  with little or slow wear , regular cleaning the filters and oiling is  important ,,best thing though is regular oil changes  for long life.

K & N good for 1.6 million km,

 

https://www.knfilters.com/cold-air-intakes?gclid=EAIaIQobChMIg56yqdXW5QIVORS3AB19GQhuEAEYBSAAEgLgQfD_BwE

You really think companies would bad mouth their own products.

Reminds me of the old saying ...

"I'm from the Government and I am here to Help You "

555

Increasing airflow = decreasing filtration? 

 

Who'd ever have thought that!!!

 

 

Of course the real world amount is too miniscule to matter. 

You obviously did not read the report ...

Or failed to comprehend what the researchers were saying

Oil analysis has repeatedly shown that the filtered media filters such as K&N do an inferior job of filtering and result in increased silicates in the oil, causing accelerated engine wear.

3 hours ago, Happy Grumpy said:

Increasing airflow = decreasing filtration? 

 

Who'd ever have thought that!!!

 

Does not have to be. I gave some examples of how one can achieve increased airflow while keeping filtration performance the same.