K&N vs. Uni air filters....

17 replies to this topic
  • squatpuke

Posted September 26, 2006 - 02:06 PM


What's the difference besides 20 bones?

  • LandSharkGT

Posted September 26, 2006 - 02:25 PM


They are both good filters! Although I have been a big fan of K&N for many years and use thier products in my cars!

  • bighugestumpin

Posted September 26, 2006 - 02:38 PM


Do a search on this topic and I think you'll hear quite a few negative things abou the K & N's filtering ability. Here's a link to a recent discussion on this topic on the XR 400 board. I recently ditched my K & N in favor of a UNI. So far so good with the UNI :thumbsup:


  • frankstr

Posted September 26, 2006 - 02:40 PM


I perfer the foam filter's for bikes.....over gause

IMO they filter as well, If not better, Plus there easier to maintain..... :thumbsup:

  • rebelventurer

Posted September 26, 2006 - 02:50 PM


I had a Uni filter in my L model, the first time I went to clean it I noticed all was not well, it was coming apart at the seams. I purchased a K&N and all has been well since I find it is just as easy to service but takes longer to dry. Foam filters are the norm with dirt bikes, but my L came with a pleated paper filter, therefore I feel that the K&N is probably a better choice for this particular bike. Besides you can add a prefilter to the K&N if you prefer.

  • philipstjohn

Posted September 26, 2006 - 03:53 PM


I use K&N in my cars/trucks but went with UNI filter on the 650R. I just serviced it, and properly oiled and greased on the seal seems to be working for me. I do not have the side plate drilled out.

  • rebelventurer

Posted September 26, 2006 - 04:09 PM


Squatpuke, man please change your avatar, I duck when I see it its gonna blow anytime and I cant imagine the mess it will make on the back side of my pc screen! :thumbsup: :lame: :p :bonk: :eek: :bonk:
Look another six pack.
I will buy you a six pack of your favorite beverage if you will change it!!!

  • drtlvr

Posted September 26, 2006 - 05:04 PM


I run a k+n air filter in my xr650L and my ds650 and have never had a problem with them if they are oiled right no dirt will enter your carb,the trick to air filters is not to clean them until you notice a power loss,I'm not talking going a whole year on a change,but cleaning your filter every ride is not necessary,unless you ride in some pretty extreme dust,how often do you change your truck filters?
every time you take that filter off you move dirt around,clean it only when it needs to be cleaned not as a part of your every ride maintenance.
this is something I learned from off road truck racers and its been working for me. :thumbsup:

  • tsizemor

Posted October 02, 2006 - 04:44 PM


When my K&N filter hit 15 years old it slighly warped and I ingested some sand in my 89 XR600R. I probably should have replaced it at the 10 year mark.

K&N offered to send me a replacement for free. I will probably take them up on their offer and sell it on eBay. It cost me $350 for new piston and cylinder plating.

Thanks to K&N I'm now running 11:1/.040 over and the bike screams. I'm also running a UNI. No more K&N.

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  • 2000 xr650r

Posted October 02, 2006 - 06:46 PM


I bought my xr650r and it come with a K&N filter. I properly cleaned and oiled it and after a off-road outing i took it out to clean. Just like everyone else says there is dust in the air box. :thumbsup: :lame: :p :bonk: :eek: :bonk: :mad: :worthy: I need a UNI asap. My k&n may be for sale or i will put it on ebay. Also if i go with the UNI will i need a backfire screen?

  • JKL

Posted October 02, 2006 - 06:52 PM


Has anyone tried NoToil filters and oil - washes out with water.

  • creeky

Posted October 03, 2006 - 03:22 AM


K&N :lame: UNI :thumbsup:

  • ghoti

Posted October 03, 2006 - 07:01 AM


It's my understanding that both flow about the same when clean, maybe an edge to the K & N. The big difference is that a foam filter will continue to flow at the same rate when it's dirty. The K & N will choke up and basically stop flowing. I have a UNI, I have run a K & N on the street, but never in the idrt.

  • SniperTeamBravo

Posted October 03, 2006 - 07:21 AM


I have K&Ns on all my cars/trucks, but UNI on all the bikes. I never could get the K&N to jet up correctly on any motorcycle like I can on a UNI filter.

  • sorenlaf

Posted October 03, 2006 - 07:35 AM


What's the difference besides 20 bones?

K&N probably provides the worst possible filtration. Sure, lots of racers use them, but their engines only have to last the race. K&N do flow well, they just don't filter well.

The ISO 5011 duramax report is no longer online, it reported that K&N allowed the most dirt to pass. Paper and oiled foam allowed the least dirt to pass.

Here's something similar.


  • eastreich

Posted October 03, 2006 - 07:46 AM


I've run both in my 650R. I ditched the K&N after about 6 months. I did not notice any difference between the K&N or the UNI. I felt that it did not stay sealed well to the edges of the airbox. I kept noticing dust sneaking past the filter into the airbox. It didn't seem to matter how much grease I put around the lip to seal it either. I've had great luck with K&Ns in my trucks, but I'll never run one in the dirt again.

I love the UNI's (I think that the Twin-Air filters are too thin), but I have since gotten lazy and just buy a new OEM Honda element (pre-oiled) when I need to change a filter. I severly modified my stock back-fire screen (no screen what-so-ever with a wire grid, 3x3 inch) to hold the filter. I do love the UNI for the sealing around the sides of the filter and the included aluminum support. I just hate to clean air filters!!!

  • TooFast

Posted October 03, 2006 - 07:49 AM


Used to use K&N but no more, not since the 80's....in both cars and bikes I've seen fine dust past the filter even when freshly oiled.

  • XR650L_Dave

Posted October 03, 2006 - 08:22 AM


I didn't detect the K&N letting any dirt through, but then I raraly ride with others.

I did have an issue with the big thick stupid rubber gasket you have to glue in for the K&N, though.


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