Filter Pole

[2006-400ex]

In your opinion which air filter is better.. the UNI air filter... or the K&N air filter???

[ZeroLogic]

depends on what type of riding i guess

snad vs mud

i would go with UNI if your not looking for a power gain and extra protection from fine dust

K&N for the power gain

[Ridin' Jesse]

IMO the UNI is better...but if i had to pcik any air filter...it would be the Pro Design...the K&N lets to much dust and dirt in.

[BlasterEaten250]

My k&n has been fine for 2 years of mud/sand/dust, and anything else you can think of. You just can't be lazy with cleaning it. jmo.

[hardkoratvmxr]

i personally have a k&n on my bike but chose the uni in tyhe poll. my k&n recently has been acting up. the whole unit like sucked part of itself in on itself so uni is what i am going to when i get enough money.

[Sjorge450R]

i havent had any problems with my K&N on my 300ex. You just have to keep them clean.

[400exrider707]

I cleaned and oiled my K&N EVERY RIDE!!! Still let dust in no matter what. I put the oil ring around where the filter clamps on, and I literally saturated the filter, still let it in. UNI all the way!

[CDCHONDAS]

Swear by a UNI, I have seen the intake boots of many K&N equipped quads with mud in them, if you are in wet conditions the uni is alot better, i actually had one on a machine with no airbox and took it through a stream crossing, there was a water line halfways up it but it never missed a beat, also my friend has a predator with a um airbox and the k&n it comes with, it seeped some mud in and proceeded to scratch his nikasil and make it smoke, so now its a 560, just remember to oil the filter either way

[speedfreaksguy]

Not again................

[04TRX400EX]

I love my K&N on my 400. If your worried about dust, run an Outerwears too. It all depends on where you ride and how much time you want to put into keeping it clean. You won't get much of a power gain out of a UNI if that's what you're after.

[Bigun55]

Get the K&N I had a uni and sold it cause i didnt like it. I could'nt tell a power differnce with the uni that y i got the K&N. Its worth cleanin to me.

[NacsMXer]

Originally posted by 04TRX400EX
I love my K&N on my 400. If your worried about dust, run an Outerwears too. It all depends on where you ride and how much time you want to put into keeping it clean. You won't get much of a power gain out of a UNI if that's what you're after.

I can attest from personal experience that K&N's suck in dusty conditions. My old setup: K&N filter, filter Outerwears, and an airbox Outerwears cleaned and properly oiled after EVERY ride. Passed fine dirt into my intake boot every time I checked it. Wipe down the inside of your boot with a white paper towel and WD-40, you'd be surprised how much dirt passes that you can't see.
Switched to a UNI and NO DIRT whatsoever using this ^^ test.

Oh, and a filter Outerwears does nothing for dust, it merely blocks large pieces of dirt from clogging the filter and adds water resistance. Like you said, it all depends on where you ride. If you're running laps behind someone on a dusty MX track, that's going to test the filter capability a lot more than you alone riding in the trails. I used to be an avid K&N guy until I tested it for myself. Having tried both filters objectively, the UNI offers the most protection for a motor.

So do you want to have no dirt in your motor and make slightly less power, or would you rather let some fine dirt in the motor for slightly more power? IMO, i'm not counting on an air filter to give my motor more power, that's the job of the motor. An air filter's job is to do just that, filter air. The horsepower difference of a K&N-equipped quad and an equal UNI-equipped quad is so small, it's not even noticable. I didn't even have to rejet when I made the switch. Don't get me wrong, K&N makes a great filter, but it only does its job properly when kept to the streets on your cars, dunes, and other low-dust conditions.

I believe there's a reason that most quads come factory with foam filters, nothing else can compare to the protection they offer in any condition.