Air filter question for you gearheads

[SGA]

Bought a K&N filter awhile back along with a outerwears filter cover. ran it for awhile, but kind of worried because it was so thin, may allow dust/dirt through. Running stock now with backfire screen removed. I noticed some of the pro engine builders do not like to use K&N, but use UNI foam type filters instead. What do ya'll think?

Great question that has no correct answer. I have run k+n filters in all my cars/trucks and some of my cycles and quads so here's my two cents worth. The reason that some racers/engine builders do not run k+n filters is that they work too good? I mean that in a good way. What happens is that when they encounter alot of water, which they stop well, they also stop air flow and shut down the engine. During a race, a rider will sacrafice an engine rebuild just to keep runnining so they choose to run a foam type filter. I have also talked to the Team mechanics from ERION racing that run Hondas 600cc roadrace team and was told that on the dyno, stock Honda filters made more horsepower and were much easier to jet. Go to the other posts on this site and notice how many questions relate to problems with jetting a quad equiped with a k+n filter. I am not taking a shot at k+n, because I have bought their products before and will do so again, but I think that you are on target with your switching back to stock Honda for your application. Are their any engine builders out their that will do some back to back dyno tests and settle this for everyone?

[Wheelie]

If you keep the K&N maintained well and run an outerwear, it won't allow any small particles to enter your engine. I personally think the K&N gives a small hp increase over the stock filter, but the stocker does a better job of keeping the crud out of the engine.

[Tommy 17]

i have had no problems with my k&n... it seems to be fine and i haven't got dirt in my motor yet... i ride in dusty, muddy, and snowy conditions so far and not one problem...

[stevengates45]

A friend & I were jetting out his warrior when he got a K&N & we found that the stock filter let air flow in faster than the K&N!

[Dave400ex]

I haven`t had any problems with K&N Air Filters. I clean my Outerwear and Filter after every ride. As long as you keep the Filter Clean and Oiled with an Outerwear on it I think you should be fine.

[knighttime]

I find it next to impossible that the K&N filter will decrease performance over a stock airfilter. I have one on my truck, and I easily noticed increased performance. I always go by an old rule of thumb: stock sucks, aftermarket better (most of the time).

I think the only possible way a stock airfilter would measure greater hp on a dyno is if the quad being tested with the K&N wasnt re-jetted.

[RideRed04]

Originally posted by knighttime
...I always go by an old rule of thumb: stock sucks, aftermarket better (most of the time)...

Naa, look at DG pipes....:D

[stevengates45]

Originally posted by knighttime
I find it next to impossible that the K&N filter will decrease performance over a stock airfilter. I have one on my truck, and I easily noticed increased performance. I always go by an old rule of thumb: stock sucks, aftermarket better (most of the time).

I think the only possible way a stock airfilter would measure greater hp on a dyno is if the quad being tested with the K&N wasnt re-jetted.

I thought the same thing when we went to put hte k&n on, but we could put a bigger jet in & run good with the stocker actually, it was some weird stuff!