K&N Air Filter 04 WR450

15 replies to this topic
  • trunkmonkey55

Posted April 22, 2004 - 12:44 PM


Anybody Know if K&N sells an Air Filter For The04 WR450 :)

  • SXP

Posted April 22, 2004 - 01:32 PM


If they do, don't use it! Buy a foam filter - less crap allowed into your motor.

  • Indy_WR450

Posted April 22, 2004 - 01:46 PM


Agreed! Buy a twin-air filter instead. They are tough and perform well. :)

  • trunkmonkey55

Posted April 22, 2004 - 05:01 PM


thanks ill stick to my foam :)

  • Rcsnowb

Posted April 23, 2004 - 07:54 AM


If they do, don't use it! Buy a foam filter - less crap allowed into your motor.

K&N claims to filter out smaller particles then foam filters. I wouldn't know for sure as I don't have one but my buddies all ride the dunes and swear that they are better at filtering then foam filters.
Yes K&N does make a filter for the WR but it's almost twice the price of the twin air.

  • SXP

Posted April 23, 2004 - 08:53 AM


K&N advertises freer flowing, doesn't clog, blah, blah, blah. This is my take on the K&N air filters:

Consider the following scenario: you with a K&N on your bike and your buddy with a foam filter on his bike, go out riding in a group. The ride is in dusty conditions, and on the average, both bikes are ridden in similar conditions - midpack, back of the pack, leading etc. At the end of the day your buddys bike runs like crap 'cause it's filter is clogged, but your bike still runs fine with the K&N even though it's dirty. Why's that? Both bikes were run in similar conditions. A similar amount of dirty air is presented to both filters, yet one clogs and the other still runs. I believe the foam filter stops the dirt right there and slowly clogs in the process, whereas the K&N, while still filtering dirt, allows a good amount of it thru to the engine.

That's my story and I'm sticking to it. I have the results of a test (long) that was conducted on different types of filters. Bottom line, the gauze/oil filters (K&N) are the worst performers with respect to small particle filteration. If you are interested, PM me and I'll email it to you (if I can find it).

  • wjc2003

Posted April 23, 2004 - 12:52 PM


I don't know if they sell one or not,but I'm with the other guys.Dont use one!>>The K&N really breaths well but if you want your engine to last,a foam filter is best.

  • simon@vic

Posted April 23, 2004 - 03:14 PM


dont ever use a k&n on dirt bike.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • YZDAD1

Posted April 23, 2004 - 03:47 PM


Yeah, what are those K&N folks thinking? All the engineering, marketing and investment dollars (probably hundreds of thousands) in a dirt bike line of filters! We're all so much smarter than them, they'll go broke, they'll put themselves out of business!!! LOL, let's set back and watch...............

  • SXP

Posted April 23, 2004 - 04:36 PM


Respect your opinion :)

Curious what your take on the clogging issue is? Why don't K&N's clog as fast as foam? I ran a K&N on my KLX650 for a while and noticed I could go a whole lot longer between cleaning as compared to a foam filter. That started bothering me and got me thinking. Then I read the results of an air filter test putting the oiled cotton gauze filters (K&N) dead last in small particle filteration and that was the clincher for me.

  • wildo

Posted April 23, 2004 - 05:02 PM


I agree w/ every one. Its not worth the mony. We put one it my buddy 250 ex quad and his intake valve was tost 6 mo. later. Of course this guys not much on matenenc. he propably never botherd to cleen and re oil the thing.

  • Indy_WR450

Posted April 23, 2004 - 06:03 PM


K&N and motorcycles do not go together! It was junk 20 years ago and it still is all marketing hype. :)

  • YZDAD1

Posted April 24, 2004 - 02:08 AM


1: foam oil filled filter surface area is exactly what you see, no folds or pleats. Only so many square inches of area.

2. K & N filter is a "folded & pleated" filter element that fits within the same air box area. That said, now unfold the filter and lay it out next to your foam filter and calculate the "square area" difference, considerable isn't it? (maybe the reason foam clogges first? :D)

3. Air filters like oil filters : tests and advertisements "educating" us on how many more microns or particulates that one brand over another filters or let through are just decision makers for the rest of us. Bottom line, any of the filters available will do a fine job, if however you elect not to service/clean them, they will all let you down eventually.

BTY: I'm not partial to either style, the choice is yours. :)

  • beezer

Posted April 24, 2004 - 02:55 AM


That is exactly right! The K&N has more filter area so it can go longer.

I would never use one a dirt bike though. They do let dirt in.

  • gfergtr74

Posted April 24, 2004 - 04:37 AM


I have used one in every vehicle I have ever owned. This being my first thumper I thought why not. In the past on my pickups the filter would clog in the pleats but the top would still be clean. I think that is why they last longer. However with all the talk about these lately I think I will be doing a little more research. I would rather lose the .25 horse power I gained with it than lose a motor.

  • simon@vic

Posted April 24, 2004 - 10:14 AM


on a dirt bike you should be cleaning your filter every ride no matter what. so why would it matter if the k&n "lasts longer" :).


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.