scott123007
Well-Known Member
I have, for many years, used every type of air filter made for motorcycles, without prejudice. I think we all have our opinions about convenience, performance benefits, and filtration, but out of sheer boredom on a rainy day I had an opportunity to dig a little deeper.
I am familiar with the posting about a V-Strom with more than 400,000 miles on an unmolested engine using 10-40 auto oil, Fram oil filters, and a K&N air filter, so all the arguments about the perceived ability of these products being inadequate are somewhat moot.
Having said that, I have also, long argued, that there is no performance benefit between one type of filter over another on a modern day bike, (without modifying the airbox), because the actual inlet air opening in the airbox is the ultimate restriction. So for all intents and purposes, this post is for all those that really want that "feel good" feeling that we are giving our bike the cleanest air possible even though it probably doesn't make a hill of beans difference in actual longevity.
The air inlet opening into the airbox is approx. 5.7 sq. in.. From there it expands to an unobstructed opening of approx. 35 sq. in. where the air filter goes. What I found very interesting, and the reason for this post, is that the actual surface area of an OEM filter (approx. 511 sq.in.) is approx. 2.3 times as much as a K&N (220 sq. in.), so even if it is twice as restrictive (as in double its ability to filter) as the K&N, it is still able to pass more air, with less pressure differential.
I get my OEM filter from my local dealer for $23.00. I take the top of my airbox off, remove the old one, and toss in a new one. Gone, for me, are the days of dipping my K&N in Mineral Spirits in two separate containers, waiting for the filter to dry, adding oil to the filter, then re-installing. Between the Spirits, filter oil, and wait time to do the job, it's just not worth it to me, to have a reusable filter, that has no other advantages.
I am familiar with the posting about a V-Strom with more than 400,000 miles on an unmolested engine using 10-40 auto oil, Fram oil filters, and a K&N air filter, so all the arguments about the perceived ability of these products being inadequate are somewhat moot.
Having said that, I have also, long argued, that there is no performance benefit between one type of filter over another on a modern day bike, (without modifying the airbox), because the actual inlet air opening in the airbox is the ultimate restriction. So for all intents and purposes, this post is for all those that really want that "feel good" feeling that we are giving our bike the cleanest air possible even though it probably doesn't make a hill of beans difference in actual longevity.
The air inlet opening into the airbox is approx. 5.7 sq. in.. From there it expands to an unobstructed opening of approx. 35 sq. in. where the air filter goes. What I found very interesting, and the reason for this post, is that the actual surface area of an OEM filter (approx. 511 sq.in.) is approx. 2.3 times as much as a K&N (220 sq. in.), so even if it is twice as restrictive (as in double its ability to filter) as the K&N, it is still able to pass more air, with less pressure differential.
I get my OEM filter from my local dealer for $23.00. I take the top of my airbox off, remove the old one, and toss in a new one. Gone, for me, are the days of dipping my K&N in Mineral Spirits in two separate containers, waiting for the filter to dry, adding oil to the filter, then re-installing. Between the Spirits, filter oil, and wait time to do the job, it's just not worth it to me, to have a reusable filter, that has no other advantages.
