Air Filter Myth

[Infamous400EX]

Recently talked with a Honda dealer and they informed me that using a K&N filter will ruin the top end on my 400EX!

True or False

[dyno]

True!!! More air but more dirt!!

[CJM]

True to a degree. Unless you keep that thing oiled and clean it will let in fine particles.

Will it cause the quad to blow up-maybe, but I doubt it. Buddy of mine runs one in his 450r with no issues. he does clean it tho.

[UnderFire]

False, My K&N is nearing 5 years old, and my bike still runs perfectly, no outerwears either. Everything from mud to sand and not a single problem yet.

[Infamous400EX]

Yeah I figured that a well maintained and oiled filter would stop more particuls than a factory sponge style.
Plus its not like it is just out in the open. Thanks for the help, I really don't want to be left walking.

[the Z Man]

good for mx but bad for dusty situations...

[bigbad400]

one of the most debated questions yet. myself i have ran k& n in every vehicle i drive, from truck to quad. years and years of use.... never have i blown one up do to a quality airfilter being the issue. put a outerwears on it if your that worried its the best flowing air filter there is and i have used everything under the sun. :o

[slightlybent47]

I run the stock foam filter with an outer filter over that. I never saw a well maintained stock filter fail. In my opinion more air = more dirt. I’ll take what little HP loss the foam filter creates for a filter that actually works. This not a debate just my opinion.

[ish416]

I have never had any issues with a KN type filter. I have been running the exact same filter on my EX since 99 and never had any issues at all with dirt getting into the intake tube or anything.

I have ran the stock foam filters to the point that they start to disintegrate. That is what originally happened to both my EX and my KFX450. They both now have KN filters.

I would say your Honda dealer is a tard.

[PaRedneckRiders]

I have ran a k@n filter on just about everything i have owned and never had one problem. As long as you keep it clean and oiled you should have no problems.
I also run an outerwares cover so that helps some.

[brokenmike]

I had a K&n filter on my 400 till I looked at it with light on the other side. It looked like a starry night. There were TONS of holes in it. I always kept it clean and oiled and I used an outerwear. Now I use a UNI filter on ally toys. I didn't notice a difference switching to a UNI either

[duroc825]

Uni for me too.

[beastlywarrior]

this is true just talk to rich, he redid a quad that was extremely well mantained and the small particles it let through wreaked havok on the throttle body and head

[Infamous400EX]

Thank you everyone, I do have the outerwares on it so I think it will be ok.

[sheweezy]

kinda off subject but also on subject... just purchased a DT1 foam filter for my rebuild...understand they make the filter for curtis sparks however his filter has a supposed "supercharged air flow ring" that comes with it...wondering if anyone has run a typical foam filter versus sparks supercharged filter....don't believe it could really have that much difference, but he also has a 20 dollar key that does seem to improve hp, so makes me slightly curious

[Thumpin440ex]

Originally posted by UnderFire
False, My K&N is nearing 5 years old, and my bike still runs perfectly, no outerwears either. Everything from mud to sand and not a single problem yet.

I am sure it runs fine, so did mine for 4 years and still did when I pulled the bike aprt.. Was crazy what the valves looked like when I had the engine done.. Def put a outerwear on it.. Cheap insurance

Or just go with UNI foam filter.. I have yet to even get a dust mark on my intake tube..

John

[slightlybent47]

This is the way I look at it. An air filter is designed to do one thing. The cubic space on a filter is limited so what some manufactures have done is pleat the filter in order to increase the cubic area of the filter while still fitting in the same space. That is a good thing because it increases air flow. But it is still a paper or paper type filter and you can only put so many holes in it because of the size of the filter. When dust passes through it, it only has a small chance to come in contact with the filter and the oil that is on it. So you have one shot to catch it before it gets to your motor. And when all those little holes get plugged up your air flow drops dramatically.

With a foam type filter it is much thicker than paper and when air and dust passes through it, it has to weave its way through the foam and the oil that’s on it. This gives it a much better chance for the filter to catch the dust before it gets through. And with so many ways for it to weave through it last longer before the air flow drops from contamination.

So I have two choices: I can use a filter that lets more air and dust in so I get more power. Or I can use one that protects my motor.
You make your own choice.


If you are a pro and have sponsors that pay for parts and mechanics’ that work on your bike. Or you can just plan afford to risk a motor for a little bit of performance then go ahead.

But for the average rider “like me” and most of you, the added increase in power is not worth it, we just can’t afford to risk a motor. Just put a little more effort in your riding skills and save your money for things you really need. Spending your money on a rebuild is no fun when you need new shocks!

[sheweezy]

anybody have any input on my post a few posts earlier????

[witech]

[i]

But for the average rider “like me” and most of you, the added increase in power is not worth it, we just can’t afford to risk a motor. Just put a little more effort in your riding skills and save your money for things you really need. Spending your money on a rebuild is no fun when you need new shocks! [/B]

The other myth is the "added increase in power"
When I dyno the race engines just for fun I used to take the air filters off to see what kind of increase no filter makes verses a filter. Most of the time on a 55 horse engine removing the air filter can gain a half horse from the stock foam filter . A K@N would be somewhere around 1/3 of a horse more than a foam. So just to put it in perspective. 55 hp with foam,55.33 with K@N and 55.5 with no air filter.
Of course that 1/3 of a horse will be gone after a few rides when the intake valves and rings start wearing and loosing compresion. Needless to say we dumped K@N"S long ago for sustained power. It was the same situation with the short skirted wiseco pistons to but thats another story .

[the Z Man]

I like this guy..... ^^^^^^^

[slightlybent47]

I had a feeling the power gains were minimal at best, I’m glad to see someone that has proof to back me up. Filter manufacturers use all kinds of marketing myths to sell filters.
Like I have always said the gains are not worth the risk!

[Honda4LifeWes36]

Hmm interesting subject.

I run K&N filter, not foam. Maybe I, too, should go with an Outwears cover?

Good idea?

[426kidz]

haha lookin into buying a UNI anyone wanna throw some $ my way for my like new K&N....good thread;)

[400exrider707]

Topic has been debated to death.

I for one, will NEVER use a K&N on any piece of equipment I own, except maybe on a snowmobile only, as it would never come near dirt anyways.

I used one on my 400ex for a while. I tried everything I could do to keep dirt from getting by. I cleaned and oiled every single time I rode that thing, and every time a quick wipe of the intake boot with a white cloth revealed some dirt specs, no matter what. I tried about 10 different brands of filter oil and sprays, including K&N's, and even different application styles, always had dirt. Switched to UNI's and problem went away. No notice in power difference.

Even if the K&N did work good, but just needed to be cleaned oiled regularly and particular attention paid to doing so, why bother? This filter costs 2x as much as a UNI, and would need more attention. The UNI was simpler, and cheaper.

After joining some diesel forums a few years back, I see those guys hate K&N even more than I do. NO ONE uses K&N's on the powerstroke boards. You can imagine how much worse the problem is on a boosted motor.

[426kidz]

I want a uni, but never had a prob with my k&n just like the uni better

[DragonGunner]

Originally posted by ish416
I have never had any issues with a KN type filter. I have been running the exact same filter on my EX since 99 and never had any issues at all with dirt getting into the intake tube or anything.

I have ran the stock foam filters to the point that they start to disintegrate. That is what originally happened to both my EX and my KFX450. They both now have KN filters.

I would say your Honda dealer is a tard.

The K&N filter on my 99' just turned 11 yrs old, its on a hybrid now. The 02' has had one since I bought it in 04'. I run open airbox, MX raced, XC race, dunes riding, swamp an mud riding, snow riding...I run a outerwear over them, when they start to get dirty I can take the outerwear off an run it for quite awhile before cleaning...cleaning I use hot water an DAWN dishsoap an scrub brush, rinse with hot water an dry, an spray even layer of K&N oil on.....usually twice a year is enough. The way the K&N filters look, they should last another 11 yrs an probably alot more....they work an they work good...the best IMHO.

[CJM]

You all are funny. You do realize that the outwears cover basically negates any dirt from getting to the KN b/c it acts as a pre filter? It also makes sure any air gains you got sucking thru that KN are now gone. That is the basic point of the KN-more air flow.

Wanna know something? I bought my pick up and someone had put a KN filter in it. The thing is the same exact design as the regular paper filters, it lets no more or less dirt in than the stock style filters. Do I really care-nope b/c in a vehicle your sucking in PCV gases anyways and it dirties everything up.

You guys choose what kinda filter you want, but foam stops more dirt from entering period.

[NacsMXer]

Originally posted by 400exrider707
Topic has been debated to death.

I for one, will NEVER use a K&N on any piece of equipment I own, except maybe on a snowmobile only, as it would never come near dirt anyways.

I used one on my 400ex for a while. I tried everything I could do to keep dirt from getting by. I cleaned and oiled every single time I rode that thing, and every time a quick wipe of the intake boot with a white cloth revealed some dirt specs, no matter what. I tried about 10 different brands of filter oil and sprays, including K&N's, and even different application styles, always had dirt. Switched to UNI's and problem went away. No notice in power difference.

Even if the K&N did work good, but just needed to be cleaned oiled regularly and particular attention paid to doing so, why bother? This filter costs 2x as much as a UNI, and would need more attention. The UNI was simpler, and cheaper.

After joining some diesel forums a few years back, I see those guys hate K&N even more than I do. NO ONE uses K&N's on the powerstroke boards. You can imagine how much worse the problem is on a boosted motor.

100% agreed.

I had the same experience when I ran K&N's on my quad. I had two filters, both with Outerwears, and cleaned/maintained them METICULOUSLY. A wipe of the intake boot after a hard dusty ride revealed fine brown dust more times than not.

The downfall to the K&N is that it passes fine dust through it. Very small particles, but it accumulates in the intake and you can see it plain as day. Like someone else said, hold one up to a light and look through the inside of it, you will see all kinds of very small holes where the light will shine through. That's exactly where the fine dust is getting through.

And another thing, Outerwears do absolutely nothing to stop this fine dust...the pore size of the holes is bigger. All an Outerwears does is block bigger particles, pieces of mud, and water from prematurely clogging the pleats of the K&N.

On a side note, I drive a F-150 with a Procharger supercharger kit on it. It came with a K&N. Every time I pull the blower to change its oil, I find the impeller covered in a very fine layer of dirt. Not good, and this is on the STREET where there is far less dust than quads see off road.

After running K&N's on the quad, I switched to a UNI foam filter. I checked the intake boots for dirt and they were squeaky clean everytime.

The reason foam filters dirt better is so simple to understand it's not even funny. You have a THICK 2 layers of coarse and fine foam. Coarse on the outside to trap large particles, and fine on the inside to stop fine dust. All this is completely saturated with sticky filter oil. Dirty air on the outside of the filter has to weave it's way through a random network of open cells in the foam in order to get inside. It's not a straight shot down, air has to zig and zag through the cells of the foam so there's a lot more time and surface area available for that dirty air to contact the filter oil.

A K&N type filter design on the other hand is a THIN layer of cotton gauze, saturated in oil, and reinforced with a screen on the outside. Air from the outside of the filter more or less has a straight shot through that cotton gauze media. There is FAR less zigging and zagging of dirty air because the cotton gauze doesn't have a random network of open cells like foam. Conversely, the air will tend to take the path of least resistance through the filter, which happens to be the holes you see when holding it up to a light. These holes are due to an inconsistent composition of the cotton gauze as well as uneven oiling. In other words, the K&N style is a LOT less forgiving b/c there is less surface area/chances for dirt to be trapped.

Thick foam is better at filtering out dirt than a thin sheet of cotton, end of story :o

[sheweezy]

I agree with CJM. I have seen dyno numbers from a k and n with and without outwears and a foam filter without an outwears, the k and n without prefilter made the highest hp, next was the foam, and then the k and n plus outwears....a k and n allows just as much dirt in as a paper based filter, a lot more dirt than a foam...SO if you have to spend more money to get the same filtering as a cheaper filter, when the cheaper filter will make more hp, is easier to clean, AND oh yeah IS CHEAPER, why would you want the k and n? There is no perfect filter system as of now, case closed. And whatever you buy is clearly a personal opinion, but it makes a lot more since to me to purchase the filter that I do not necessarily need to buy a prefilter for protection, makes more hp versus the competitor that needs a prefilter, and is cheaper...I personally run DT1 foam filters, and will continue to run a foam filter until someone decides to sit down a design a filter system that uses liquid to catch dirt, dust, and debris and can still have the same air flow as the filters we have now.....

[MidnightBlade]

UNI's in the quads, bikes, and sleds
K&N on the trucks, my IDI is non turbo though

[2001400exrida]

my uni filter can be as dirty as can be on the outside but when i take it off and look inside the foam filter it's spotless!

Does anybody else get dirt and crud in their airbox even with the lid on? If i ride hard through some mud i notice that my airbox and filter and filthy after a day on the trails. If it's dry it's not so bad but when i spray it off it's like water is getting into my box somehow, i know some goes through the snorkel but still

[CJM]

Ive had mud and other things lightly coat the bottom of the box before, think its mostly from the snorkel.

I have an outerwears lid on mine (the kind you cut and bolt on) and it doesnt let much in tho.

[Honda4LifeWes36]

You guys aren't running with the snorkel on?

[slightlybent47]

I just went longer then I ever have without cleaning my air filter just to see how well it would do. I run the stock foam filter with an outer foam filter over that and soaked in bel ray foam filter oil. I also run with the lid off and no snorkel so it gets very dirty.
I took the outer filter off and she was spotless on the inner stock filter, then I took a clean white rag and swabbed up inside the intake tube and she was spotless. I didn’t even need to clean the inner filter but I did it anyway and found zero dirt in it. The outer filter was covered solid in dust and dirt. This tells me my filter is doing exactly what it is designed to do.
I have seen my friends use K&N and they always have dirt in the intake, I’ve been there when they clean it and dirt is always there. That’s why I like the foam filters, they work.

I drove an off road Mack truck for years and I can tell you this, they use a very large air filter about 2 feet long and a foot in diameter. They are a pleated paper filter just like K&N but much larger.
After a few months of driving in hot dry conditions I can see the filter monitor on the air filter getting higher, which means the dirt is clogging the filter and not enough air is getting in. if you don’t change it the truck won’t run very good and it loses power.
And sometimes when it was dirty like that and I ran through a thunder storm and moister gets in the air filter it will make the dust and dirt turn to a thick past and the truck would lose all power and not even run. I have had to remove the air filter and she starts right up and runs fine.

Paper filter just don’t do the best job at cleaning the air like foam filters do. Paper filters do flow better but at a price. Is that ¼ hp worth risking a $2000.00 rebuild?

[WoodTRD]

My take one it is foam (UNI) for offroad/ high dust conditions, K&N for street/ low dust. I've ran the same K&N for nearly 200k miles on my Tacomas and its held up amazingly, but in a year it doesn't see the same dust as my bike does in 2 rides. The intake after the filter is always spotless on my 400, no matter what the outside of it looks like. For my conditions a UNI foam filter with my home made outerwears lid does pretty good

[DragonGunner]

Originally posted by CJM
You all are funny. You do realize that the outwears cover basically negates any dirt from getting to the KN b/c it acts as a pre filter? It also makes sure any air gains you got sucking thru that KN are now gone. That is the basic point of the KN-more air flow.

Wanna know something? I bought my pick up and someone had put a KN filter in it. The thing is the same exact design as the regular paper filters, it lets no more or less dirt in than the stock style filters. Do I really care-nope b/c in a vehicle your sucking in PCV gases anyways and it dirties everything up.

You guys choose what kinda filter you want, but foam stops more dirt from entering period.


Ha..glad I'm funny....I had always heard good things about K&N, thats why I bought it, an yes i bought the pre-filter for added protection...cost...37.00 for the K&N an 8.00 for the prefilter an over 10 yrs of service....I do agree that Foam filters have the record for keeping things cleaner....all I'm saying is the K&N has been doing the job that I bought it for.....sorry if it doesn't work for someone else. Guess I'm just lucky.....an funny.
O, an as far as a outerwear slowing the air flow..."which is the point of the K&N.."....ya it might....a little....how much...? I let u run mine with an without the outerwear....an if you can tell when its off an when its on, I'll give u a cookie.

[dsm_racing]

[i]I drove an off road Mack truck for years and I can tell you this, they use a very large air filter about 2 feet long and a foot in diameter. They are a pleated paper filter just like K&N but much larger. [/B]

Probably a Donaldson type filter. If it's dusty conditions you're worried about, that's the answer. It's what all your heavy equipment runs. I adapted one off a Bobcat for my RZR.

Other than that, I've run a K&N on all three of my 400's for years now and have never had a problem. But I run outerwears on them. I've never had any issue with dirt getting past the filter. I even pulled a UNI off one of them to put the K&N on. I personally just don't like the foam filters. They've never seemed very robust to me. But as some people have already said, I don't think there's a nickel's worth of difference between the two as far as filtering, horsepower, and probably even run time between cleanings. I think it really does come down to personal preference.

As far as the original poster's comments from the dealer, let's all remember that the dealer wants to sell overpriced dealer parts. Service items like filters and oil is where they really make a killing.

[CJM]

I wasnt picking out anyone particular Dragon. Just saying that the purpose of the KN is to allow more air in-which it does, but using an outwears filter over it totally negates the above.

Like I said, your money, your quad you guys can do what ya want.

[MidnightBlade]

Originally posted by DragonGunner
O, an as far as a outerwear slowing the air flow..."which is the point of the K&N.."....ya it might....a little....how much...? I let u run mine with an without the outerwear....an if you can tell when its off an when its on, I'll give u a cookie. And I'll let you ride mine with the stock filter and the K&N and see if you can feel that .1 HP that I gained while destroying my topend :rolleyes:

[DragonGunner]

Originally posted by MidnightBlade
And I'll let you ride mine with the stock filter and the K&N and see if you can feel that .1 HP that I gained while destroying my topend :rolleyes:

Actually I would bet a cookie that I could tell the difference on that. Wow, never heard of a K&N destroying a 400EX top end, I don't blame u for not liking them. If u were keeping it clean, oiled an checking the airboot when having it off an it did this, I would buy something else too.

[NacsMXer]

Originally posted by DragonGunner
Actually I would bet a cookie that I could tell the difference on that. Wow, never heard of a K&N destroying a 400EX top end, I don't blame u for not liking them. If u were keeping it clean, oiled an checking the airboot when having it off an it did this, I would buy something else too.

I was doing all of that while I had my K&N. Maintaining it by the book and checking the boot each time I cleaned it.

And for the record, I seized both my intake valves at the end of the day riding in some thick dusty conditions while I had a K&N. I'm not 100% blaming the K&N for that, i'm still not sure what caused it but I guarantee the fine dirt in the intake tract wasn't helping any.

It was at that point I sent the whole motor off to GT Thunder to be repaired/built up. After I got it back, I switched to a UNI foam filter and haven't had a problem with the dirt in the intake since.

[AtvKid4Eva]

If your worried about dust with a K&N just run a pre filter over it..i've always ran K&N filters on all my bikes in some pretty dusty situations and have never had a single problem. Proper maintenance is key.

[MidnightBlade]

Like stated above I don't blame the topend eating itself entireley on the K&N. Also throwing this out there, it wasn't my bike but I had the pleasure of helping rebuild it.

Oh, and AtvKid4Eva we already stated that any small gains from the K&N would be worthless with the prefilter

[AtvKid4Eva]

Ok, when i had my 400 i ran a K&N and never had a pre filter on it and rode it in heavy heavy dust all the time and never had and motor problems. On my 450 i do run a pre filter just because the small power loss (if any) is not going to be noticeable to me while riding.

[CJM]

I say: Run what ya want, just dont come crying if something goes wrong.

Like I tell everyone-do it right the first time.

[426kidz]

yeah, well an Air filter wont make a dif when your ridding you will never feel any lose....if you want to feel a differance get a full system or go bigger on the motor! K&N is a great company and so is uni but if you take care of your equipment there will be no problems. I run a K&N open lid and no outerwear just oil it regularly...NOT A SINGLE PROBLEM!;)

[426kidz]

O and by the way....the Honda dealer will tell you anything to get your hard earned money into their pocket! They want you to use all there products and stay stock mostly! so yeah a K&N Will not ruin your top end lol thats so funny!:p

[DragonGunner]

Originally posted by NacsMXer
I was doing all of that while I had my K&N. Maintaining it by the book and checking the boot each time I cleaned it.

And for the record, I seized both my intake valves at the end of the day riding in some thick dusty conditions while I had a K&N. I'm not 100% blaming the K&N for that, i'm still not sure what caused it but I guarantee the fine dirt in the intake tract wasn't helping any.

It was at that point I sent the whole motor off to GT Thunder to be repaired/built up. After I got it back, I switched to a UNI foam filter and haven't had a problem with the dirt in the intake since.

Just wondering if you had a outerwear over it? If I had the same thing happen I would of done the same as you, got to believe in it or change, sounds like you lost confidence in the K&N even though it may not of been the problem....I read awhile back a guy rented a 400EX at the dunes for 3 days...ran great the whole time, returned it an as they were inspecting it, they dicovered it had no airfilter!!!!!!!!!!!!!!! The renter had clean it an forgot to put it back in, said there was alot of sand in that box...who knows how much longer it ran after that, but it was still running good...said that says alot for the 400EX...when I had my head ported a few yrs. ago he said the valves were OK, but was getting close to the end, so I had them replaced, there was alot of hours on it with the K&N, including the time it went under in 4' ft. of sandy muddy water, got the water out an finally got it started an drove it over a half mile. lots of oil changes...everyone said sell it fast, its ruined....7 yrs. later its still running perfect.

[NacsMXer]

Originally posted by DragonGunner
Just wondering if you had a outerwear over it? If I had the same thing happen I would of done the same as you, got to believe in it or change, sounds like you lost confidence in the K&N even though it may not of been the problem....I read awhile back a guy rented a 400EX at the dunes for 3 days...ran great the whole time, returned it an as they were inspecting it, they dicovered it had no airfilter!!!!!!!!!!!!!!! The renter had clean it an forgot to put it back in, said there was alot of sand in that box...who knows how much longer it ran after that, but it was still running good...said that says alot for the 400EX...when I had my head ported a few yrs. ago he said the valves were OK, but was getting close to the end, so I had them replaced, there was alot of hours on it with the K&N, including the time it went under in 4' ft. of sandy muddy water, got the water out an finally got it started an drove it over a half mile. lots of oil changes...everyone said sell it fast, its ruined....7 yrs. later its still running perfect.

I had 2 Outerwears, one on the K&N and one on the airbox lid. Like I said before, the Outerwears do nothing to stop the fine dust that K&N's let through. The fine dust particles are smaller than the pore size in the Outerwears....they only stop the larger particles, chunks of mud, sand, and water from prematurely clogging up the K&N. Me finding fine dust in the intake each time I cleaned the K&N proves that those two Outerwears did nothing to stop it.

I lost confidence in the K&N because it kept letting dirt through. After getting my motor freshly rebuilt I didn't want to mess around any more so I decided to give foam filters a chance. The foam filters have not once let dust or dirt through so i'll continue to run them.

[slightlybent47]

The fine dust that we are trying to keep out of the motor is made of silica (sand) and it is much harder then the metal parts in the motor. Even very small partials will destroy your motor over time. That’s why every atv manufacture uses foam filters on there bikes (they work) if K&N was so good and made that much more power, then don’t you think they would use them?
Some of you guy’s get it and some don’t, the ones that don’t keep the mechanics busy.

[426kidz]

no wrong ...foam ones are cheap as hell and easy to clean. they also use gay lookin bars and cheap grips and crappy tires etc. if your tryin to say you keep all your stock parts on because there so strong and work so great than you must not ride very hard... clean and the motor will run fine!:o not being an *** but just keeping it real;)

[slightlybent47]

Originally posted by 426kidz
no wrong ...foam ones are cheap as hell and easy to clean. they also use gay lookin bars and cheap grips and crappy tires etc. if your tryin to say you keep all your stock parts on because there so strong and work so great than you must not ride very hard... clean and the motor will run fine!:o not being an *** but just keeping it real;)


We aren’t talking about other parts, just filters. Bars are made to fit a wide verity of riders, and just because you don’t like the way the look, doesn’t mean they don’t function the same. The tires are used as general use tires for a verity of conditions as all purpose tires.
And really do you think foam is any cheaper then paper?

[DragonGunner]

Originally posted by slightlybent47
The fine dust that we are trying to keep out of the motor is made of silica (sand) and it is much harder then the metal parts in the motor. Even very small partials will destroy your motor over time. That’s why every atv manufacture uses foam filters on there bikes (they work) if K&N was so good and made that much more power, then don’t you think they would use them?
Some of you guy’s get it and some don’t, the ones that don’t keep the mechanics busy.


Last sentence wrong.....a zillion hours an 11 yrs on K&N....no mechanic needed....lets not paint tooooo broad here an make stuff up to fit your beliefs. If K&N was so bad they wouldn't be in busines an they wouldn't be running them in the deserts...or anywhere.

[426kidz]

yeah a foam filter is cheap...uni is 20.00 and "paper" K&N are 50.00...for a reason there better and like said they would have messed my 426 up a long time ago if what you are saying is true and they would also be out of bussiness,and no stock bars are weak and cheap...and why put an all purpose tire on a sport quad...cuz its the cheap way!idea of a quad is to build it as cheap as you can and let the buyer BUY and buld it to their specs and Upgrade it my other parts are just examples of what we are talking about. .:o

[slightlybent47]

Originally posted by 426kidz
yeah a foam filter is cheap...uni is 20.00 and "paper" K&N are 50.00...for a reason there better and like said they would have messed my 426 up a long time ago if what you are saying is true and they would also be out of bussiness,and no stock bars are weak and cheap...and why put an all purpose tire on a sport quad...cuz its the cheap way!idea of a quad is to build it as cheap as you can and let the buyer BUY and buld it to their specs and Upgrade it my other parts are just examples of what we are talking about. .:o


It’s called marketing, and pitch men have been doing it since the dawn of time. Just like the commercials where they make something look bad in order to sell there product.
So you are paying more money for something that doesn’t work as good, not much of an argument if you ask me.lol
People like you always bring up something else to change the subject when there argument is week. And some of you are comparing a street ride to an off road ride, there’s a big deference. We are talking filters on ATV’s not other parts or other rides.

[AtvKid4Eva]

Ok, they are both good filters. who cares. they both have their strong and weak points. if your going to ride in dusty conditions buy a UNI. If your gonna ride in non dusty conditions buy a K&N. Theres no more argument. Ive ran K&N's for a long time on all my bikes and have never had a problem, ive also known many people who use UNI's and havent had a problem either. Buy whatever you want.

[426kidz]

ATVKID4eva your right....and slightlybent47 my statement is not " weak OR like you call it "Week"


"Never argue with an idiot, they will just bring you down to their level, then beat you with experience."


AGREE to disagree.:D :D :D

[MidnightBlade]

Originally posted by 426kidz
ATVKID4eva your right....and slightlybent47 my statement is not " weak OR like you call it "Week"


"Never argue with an idiot, they will just bring you down to their level, then beat you with experience."


AGREE to disagree.:D :D :D
Must be why we got this argument started :tired:

[slightlybent47]

Food for thought: this thread and many others like it have been debated to death. But one thing stands out over anything else. Not once has anyone said that there foam filter didn’t work. Only K&N filter users post how the K&N failed.
I’ve never used Uni so I have left them out of the argument, and we all agree foam filters are the best for filtering dust and dirt, paper filters do flow better but at a price, your engine.

[MtnEX]

Well here is the end all end bottom line on the subject...


Those who have success with K&N filters long term either do not ride dust bowl days, or more likely than that, the dust particulates in their area are not all that small. PERIOD.

For example there is a heck of a lot of difference in the size of a western sand particle, and an eastern sand particle, and even more difference than the size of a particle of dust off dry clay, loam or limestone soil.

I have tried every way there is to do it, and every cotton gauze filter passes dust here like it is not even there. The dust particulates here are way smaller than the pore openings on these filters and there is not sufficient depth of media for it to get oil-trapped.

And when you run a cotton gauze filter a little while, the weave of the gauze starts to separate as well... so they develop holes in them so large that about anything but sand can pass right through. Next time you clean it, hold it up to a light...

I have to run foam or rebuild real often and that is just the bottom line.

[MtnEX]

This is an example of my results with K&N after a couple hours of trail riding and being the guy in front the whole time.

Results are the same no matter what kind of oil you put on it... even the super tacky blue Maxima aerosol you can use on K&N or foam.

It just can't stop the dust particles in my area. The oil I fog my tube with caught more dust than the filter did and that is no joke.

[89trx250r]

hey man taking that snorkle of would probably help you if you plan on riding behind people cause what it does it funnels air and dirt from the front of the quad at high speed into your air box i could ride for a month in the desert and my airbox would probably not even look like that :0

[CJM]

Interesting mtn. I ride very sandy, dusty areas too and it never gets in there like that at all.

[AtvKid4Eva]

Originally posted by CJM
Interesting mtn. I ride very sandy, dusty areas too and it never gets in there like that at all.

Same here. Ive ridden is such dusty conditions i couldn't see 5ft in front of me and have never has dust inside my intake tube. But in your case def get a different filter lol.

[NacsMXer]

Originally posted by AtvKid4Eva
Same here. Ive ridden is such dusty conditions i couldn't see 5ft in front of me and have never has dust inside my intake tube. But in your case def get a different filter lol.

Good post by MtnEX. I had pretty much the same results with my K&N, just not as much dust in the intake boot. My K&N's also looked the exact same with the irregular pattern of holes you can see light through. As a matter of fact I have never seen a cotton gauze media filter such as a K&N, S&B, Airaid, etc NOT have those holes in it after normal use. Like I said before, I believe these holes to be caused by the manufacturing process to make the cotton gauze layer. What you have is fibers of cotton weaved into a pattern. That weave is never going to be homogenous or consistent from one area on the filter to the other (at the microscopic level). There will be thin spots and thick spots, as well as thin areas where the cotton fibers have "shifted over" one way or another (this gets worse with normal use/cleaning). When the fibers get shifted over enough, you develop those holes you see. On top of all this, the layer of cotton gauze in a K&N is no more than an 1/8 of an inch thick, so your overall filtering surface area, and chances for catching dirt go way down compared to foam.

Foam filters on the other hand are able to have a much more consistent and homogenous filter construction during the manufacturing process. If you examine 0.5 cubic inches of foam from one side of the filter under a microscope, and then look at 0.5 cubic inches of foam from the opposite side of the filter, the amount of foam to open cell ratio is going to be pretty close to the same. Not to mention you have 2 layers of thick, I repeat THICK foam that fine dust has to work its way through to get inside. The random cell structure of the foam creates a LOT more surface area that the dirt has to weave its way through compared to a K&N. The foam filter will in turn have a more consistent ability to filter particles big and small. With the K&N, it may stop the big and medium sized particles, but anything smaller than those large irregular holes in the cotton gauze filter media is going to get in, end of story.

Next time after a really dusty ride, remove your K&N (should need a cleaning anyway). Take a white paper towel, spray some WD-40 on it and wipe the inside of the intake boot as best as you can (get your arm up in there lol). I never got dust as bad as the pic MtnEX posted, but when I took a paper towel with a little WD-40 on it and wiped it, it came out in brown streaks. You can't take a quick glance at the intake boot or a finger swipe, you're not always going to see that fine dust.

[MtnEX]

Originally posted by CJM
Interesting mtn. I ride very sandy, dusty areas too and it never gets in there like that at all.


Originally posted by AtvKid4Eva
Same here. Ive ridden is such dusty conditions i couldn't see 5ft in front of me and have never has dust inside my intake tube. But in your case def get a different filter lol.


You all missed my point....

It's not about the quantity of dust you ride it.

It's about the size of the dust particles in your area.

Our dust is very small in particle size and passes right through.

[MtnEX]

I even tried this oil which was the only super tacky oil I could find for gauze filters... and it works awesome on foam...

http://www.maximausa.com/shopping/index.php?main_page=product_info&cPath=5&products_id=31&zenid=v4kgaataifs0v95slg3ltperu0

http://www.maximausa.com/shopping/images/FAB1.png


You can see the filter in the background in this pic with this oil on it (it's blue) and you can see that again there is more dust stuck to the fog oil in the tube than in the filter... Dust is able to pass without touching the oil, because it is super tacky and everything that touches it sticks.

[slightlybent47]

MtnEx
You can talk till your blue in the face and there will be someone that will argue with you, and some of those have no clue as to what they are talking about. Some get it but post dumb chit just to keep the argument going.

The word you’re looking for is “Micron” it’s the unit of measurement use to describe small particles like dust. All filters are tested to see how well the work and they are given a rating in microns. The deference with a foam filter is in how thick it is and the path the air has to take to pass through. A foam filter makes the air and the dust it carries weave its way through the filter. This gives the dust a chance to come in contact with the oil in the filter and stick. With a stock foam filter and an outer foam filter over that, I have three layers of foam that get smaller as it gets deeper in the filter.

[uchi]

mine was put in in 2003, its been sunk in mud past the headlights, even with the drilled lid ive had the airbox full of mud and the intake tube was always clean, just keep it clean and oiled.

[MidnightBlade]

Originally posted by uchi
mine was put in in 2003, its been sunk in mud past the headlights, even with the drilled lid ive had the airbox full of mud and the intake tube was always clean, just keep it clean and oiled. And here is "The One" person you were talking about SlightlyBent

[MidnightBlade]

Originally posted by uchi
mine was put in in 2003, its been sunk in mud past the headlights, even with the drilled lid ive had the airbox full of mud and the intake tube was always clean, just keep it clean and oiled. And here is "The One" person you were talking about SlightlyBent

[uchi]

Originally posted by MidnightBlade
And here is "The One" person you were talking about SlightlyBent

are you saying im talking just to keep the argument going? theres no argument from me. ive had my quad since 04, in 03 the original owner tossed in a k&n. the motor has never been apart. its been maintained somewhat but runs smooth, doesnt tick knock or anything. i kick the piss out of it and ive brought it home and spent 40 minutes power washing it because i found that much mud. the air filter stops alot of **** from getting in, clearly it wont stop everything and once you soak it itll start sucking in water and mud through it. but as i said, i clean mine alot. anytime i get her muddy the filter gets cleaned and theres never been crap in the intake tube past the filter. :)

[riotact]

No problems with Uni here so I'm not gonna change.Maby one day I'll check out K&N but we'll see. :cool:

[MtnEX]

Originally posted by slightlybent47
MtnEx
You can talk till your blue in the face and there will be someone that will argue with you, and some of those have no clue as to what they are talking about. Some get it but post dumb chit just to keep the argument going.

The word you’re looking for is “Micron” it’s the unit of measurement use to describe small particles like dust. All filters are tested to see how well the work and they are given a rating in microns. The deference with a foam filter is in how thick it is and the path the air has to take to pass through. A foam filter makes the air and the dust it carries weave its way through the filter. This gives the dust a chance to come in contact with the oil in the filter and stick. With a stock foam filter and an outer foam filter over that, I have three layers of foam that get smaller as it gets deeper in the filter.

Yeah, I know, but these guys wouldn't know what the heck a "Micron" is.

And I know some guys will just keep it going for fun.

Most of them don't know I have been doing extensive testing and development on an intake system for another model ATV and can smell BS through a computer screen as a result.


I've been testing oils and filter medias to death for protection both in the wet and dry.


They don't know I know first hand that a lot of filters don't filter much, outerwears are not water proof, lots of oils are not so much as even water resistant, and lots of oils that are waterproof do not stop jack from passing through cotton gauze because of such a high percentage of direct open unprotected pathways.



They can tell their tall tales all they want, but should know I know better.



So far I have not been able to get any power gains from anything over foam... and I have not been able to find another media that can filter out the dust as well either....

I'm about to test a new synthetic media though to see how that goes. We'll see...

[uchi]

Originally posted by MtnEX
Yeah, I know, but these guys wouldn't know what the heck a "Micron" is.

And I know some guys will just keep it going for fun.

Most of them don't know I have been doing extensive testing and development on an intake system for another model ATV and can smell BS through a computer screen as a result.


I've been testing oils and filter medias to death for protection both in the wet and dry.


They don't know I know first hand that a lot of filters don't filter much, outerwears are not water proof, lots of oils are not so much as even water resistant, and lots of oils that are waterproof do not stop jack from passing through cotton gauze because of such a high percentage of direct open unprotected pathways.



They can tell their tall tales all they want, but should know I know better.



So far I have not been able to get any power gains from anything over foam... and I have not been able to find another media that can filter out the dust as well either....

I'm about to test a new synthetic media though to see how that goes. We'll see...

im not gonna read through 8 pages of **** that went on in this thread, when i replied it was from personal experience and results ive seen because of it. its not to question your research because frankly im not an expert in the field of filter dynamics and air molecules and other fancy **** like that, lol. what type of filter do you recommend to use that will filter the best and let the most air through? my k&n is gonna start looking like a hookers ***** this year and i think its seen its million miles prematurely from mud dirt and bottles and bottles of oil and cleaner. so im gonna upgrade.
those filter covers that look like panty hose, i dunno they seem fine but its a piece of screen thats supposed to keep stuff out, logically it doesnt work. maybe you could help it along by using some sort of spray on protector like you do to protect shoes from water and dirt.

an air filter is only so good. the more air you wanna get to make power the more stuff is gonna get sucked through it. its that simple. things will get through especially if the filter is soaked, then itll start sucking water and mud through. thats why you gotta be prepared to clean it after each ride if thats how you plan on playing.

hell my last car was turbocharged in my garage, i ran a piece of chicken wire over the turbo to keep rocks and bugs out and it made tons of power without a filter. id avoid dusty roads but im sure things still got fed through it, ran it like that for a full season with lots of miles and didnt once suck in anything that caused an issue :D

[slightlybent47]

Haven’t you been paying attention? Foam filters do the best job in dusty situations.
For those of you who don’t get it here is a picture for your reference.

I use a stock foam filter with a foam outer filter over that and both are soaked in Bel-ray foam filter oil. And trust me it works as good or better then anything else I have used.
You can see by how dirty the air box is and how clean the filter is, that’s a clean filter in a dirty air box. Yeah I know I should clean the air box and I usually do but I was in a hurry and I just wanted to get the filter back on till I have a chance to go back and clean it.

http://i53.tinypic.com/23w5ief.jpg
http://i53.tinypic.com/30at3wj.jpg

[MidnightBlade]

Originally posted by uchi
hell my last car was turbocharged in my garage, i ran a piece of chicken wire over the turbo to keep rocks and bugs out and it made tons of power without a filter. id avoid dusty roads but im sure things still got fed through it, ran it like that for a full season with lots of miles and didnt once suck in anything that caused an issue :D Was the car a DD or Drag use only?

[uchi]

cant you read? i said im not reading 8 pages of **** just to throw in my 2 cents.

i may look into getting one of those sponge covers to toss over my k&n just to be on the safe side as i have been running alot more mud in it lately than usual.


Originally posted by slightlybent47
Haven’t you been paying attention? Foam filters do the best job in dusty situations.
For those of you who don’t get it here is a picture for your reference.

I use a stock foam filter with a foam outer filter over that and both are soaked in Bel-ray foam filter oil. And trust me it works as good or better then anything else I have used.
You can see by how dirty the air box is and how clean the filter is, that’s a clean filter in a dirty air box. Yeah I know I should clean the air box and I usually do but I was in a hurry and I just wanted to get the filter back on till I have a chance to go back and clean it.

http://i53.tinypic.com/23w5ief.jpg
http://i53.tinypic.com/30at3wj.jpg

[uchi]

Originally posted by MidnightBlade
Was the car a DD or Drag use only?

daily driver, the only thing it didnt see was snow because the sub frame tie brace would fill the back of the engine compartment with snow and thats where the turbo sat. drove the car rain or shine and i was always in the boost. all of my buddies who have or had turbo cars that made decent power would do the same. the car builds boost alot faster when it isnt being forced to suck air through an air filter. was it safe, maybe, i didnt go down dirt roads but then again i wouldnt have done that with an air filter on with that car. but it ran great like that :)

[slightlybent47]

This is the question we are talking about.


Originally posted by Infamous400EX
Recently talked with a Honda dealer and they informed me that using a K&N filter will ruin the top end on my 400EX!

True or False


A street car is nothing like an off road ATV, so the comparison is not the same.
You’re jumping off the subject. If you would have took the time to read through the whole thread, you would have seen that we are only talking about off road ATV’s. Not cars, trucks, lawn mowers or anything else because it wasn’t the ordinal question. Thanks for the input but do you have any experience with an off road ATV? Read the whole thread and you might learn something.
Some folks seem to have good luck with a K&N but the majority seems to go back to a better filter after seeing dirt getting through in this application.
No one is trying to force anyone to change there filter, we are just here to see what everyone is using and how well it is working.

[CJM]

I say ya run whatever filter you want, but if it blows up dont cry about it.

[slightlybent47]

Originally posted by CJM
I say ya run whatever filter you want, but if it blows up dont cry about it.


Yep that sounds good to me!

[uchi]

Originally posted by slightlybent47
This is the question we are talking about.




A street car is nothing like an off road ATV, so the comparison is not the same.
You’re jumping off the subject. If you would have took the time to read through the whole thread, you would have seen that we are only talking about off road ATV’s. Not cars, trucks, lawn mowers or anything else because it wasn’t the ordinal question. Thanks for the input but do you have any experience with an off road ATV? Read the whole thread and you might learn something.
Some folks seem to have good luck with a K&N but the majority seems to go back to a better filter after seeing dirt getting through in this application.
No one is trying to force anyone to change there filter, we are just here to see what everyone is using and how well it is working.

clearly i have no offroad experience at all on an atv, or in a truck. im just the guy who ran one of the largest off road clubs in ontario, for atv's and trucks, and ive had my share of both. but clearly i have no idea about anything when it comes to offroading, atvs, or the purpose of an air filter. :)

listen im not gonna get into a pissing match with you, at no point did i say a foam filter was crap, at no point did i say it was better or worse than a k&n filter. im simply adding what im using to this thread. a k&n has its place. i like it on anything thats offroaded because its serviceable. a foam filter may work but its a sponge, and when it gets wet, just like the cotton element, itll allow water through it, be it water thats been filtered and has turned into clean water or dirty water, youre still sucking something in. you wanna keep your filter dry, build a snorkel and put it 5 feet over your head with a 180 degree bend. guaranteed to keep your filter dry.

a k&n also doesnt belong in alot of places. alot of bikes dont like tham because they let in too much air and make tuning a ***** and create nice big fat flat spots in the power band. cars with mass air sensors shouldnt use them because the oil from the filter will damage the sensor. even when you think its dry its still wet.

it has its place, im not disputing anything that you or anyone else intelligent has said regarding filters. im sure at some point im bound to suck in water and probably hydrolock my little 400. but if i get enough water in there sponge or cottom filter it doesnt matter, its sucking in water. :)

[uchi]

and dont take anything im saying personally, im just having fun with you man and razzing you a little. little bit of winter off season fun for those of us living in snowy climates :)

[slightlybent47]

Originally posted by uchi
and dont take anything im saying personally, im just having fun with you man and razzing you a little. little bit of winter off season fun for those of us living in snowy climates :)


Hey I here ya! Some folks don’t know squat when it comes to common since. Knot knowing your background I don’t know what your experience is, so I’m just razzing you a bit as well.
Water brings on a whole deferent element in this subject, and no filter is perfect.
I agree that in some allocations better air flow out weights the risk of contamination.
If I had the money to rebuild every year and that little ¼ HP was a concern then I would run a K&N or something like it.
That ¼ HP gain I would get is not going to win races, but the way I ride will.
If your looking for reliability and long life out of your motor, keeping it clean will help as much as anything.

[uchi]

Originally posted by slightlybent47
Hey I here ya! Some folks don’t know squat when it comes to common since. Knot knowing your background I don’t know what your experience is, so I’m just razzing you a bit as well.
Water brings on a whole deferent element in this subject, and no filter is perfect.
I agree that in some allocations better air flow out weights the risk of contamination.
If I had the money to rebuild every year and that little ¼ HP was a concern then I would run a K&N or something like it.
That ¼ HP gain I would get is not going to win races, but the way I ride will.
If your looking for reliability and long life out of your motor, keeping it clean will help as much as anything.

agreed and a high flow filter wont make enough of a different on a small displacement single piston motor to be worth using. mine came with it so its stayed because so far its worked for me. i will however run a setup like in the above pic with the sponge and sponge over top once i rebuild this motor. im thinking of doing something mild like a 416 and maybe a cam with a garage port job just to wake it up a little and that motor ill want to protect. i think im the type of person where sub consciously i want this motor to blow up just to give me a reason to build one, lol.

maybe its been discussed already in here, its just after 7 am and im still sleeping so i wont find it if i look. since my lid is drilled i tend to get some mud in there which forces me to clean my filter. what are your views on those screens that go over top of the air box, i wanna say theyre made by outerwears but i could be wrong. im thinking of getting one of those or even some pantyhose and maybe treating it with a spray on shoe protectant to make it a little bit more water proof but still allow it to breathe. just to keep some water out of the air box to give the filter a bit of a better chance of not sucking up water.

[MtnEX]

uchi,

Just use oiled foam for off-road applications.

Put a UNI in place of the K&N... cheap and simple.

There is no power difference or jetting difference between them in my opinion.

In fact this has been dyno proven.

[DragonGunner]

I wonder if any Pro XC GNCC racers an teams ran K&N on the dusty race tracks on the circuit.....?......yes they did. O' the humanity....lol

[slightlybent47]

Originally posted by uchi
agreed and a high flow filter wont make enough of a different on a small displacement single piston motor to be worth using. mine came with it so its stayed because so far its worked for me. i will however run a setup like in the above pic with the sponge and sponge over top once i rebuild this motor. im thinking of doing something mild like a 416 and maybe a cam with a garage port job just to wake it up a little and that motor ill want to protect. i think im the type of person where sub consciously i want this motor to blow up just to give me a reason to build one, lol.

maybe its been discussed already in here, its just after 7 am and im still sleeping so i wont find it if i look. since my lid is drilled i tend to get some mud in there which forces me to clean my filter. what are your views on those screens that go over top of the air box, i wanna say theyre made by outerwears but i could be wrong. im thinking of getting one of those or even some pantyhose and maybe treating it with a spray on shoe protectant to make it a little bit more water proof but still allow it to breathe. just to keep some water out of the air box to give the filter a bit of a better chance of not sucking up water.



If you run in mud on a regular basis then I would use the snorkel that came with the bike. I don’t recommend running in water without it, that’s what it was designed for. The foam filter pic is my set up and it works for me riding mx, and that’s just about all I do with my ex. If you use my set up dust will no longer be a problem, but it won’t do much against water though.
I run without an air box lid but it dose trap more dirt because the dirt bonuses off the bottom of the seat pan and goes, right in the air box, that’s just another reason I use a good filter set up. If you run without the air box lid and water gets over the top of the box, no filter will stop the water from getting in. I do use bel ray foam filter oil on the filter because it has worked best for me when it comes to water diluting the oil on the filter but it’s not water proof.
As for the top riders running K&N filters, they have sponsors that pay for rebuilds so money is not an issue. Also they generally rebuild every season anyway, and if had plenty of money then I would care about the rebuilds ether.

[MtnEX]

Originally posted by DragonGunner
I wonder if any Pro XC GNCC racers an teams ran K&N on the dusty race tracks on the circuit.....?......yes they did. O' the humanity....lol

Those who don't DNF in the dust bowls are using foam.... and an extra layer of foam stuffed in the air box over the filter.

Run so long until the bike starts getting lazy... pit, remove the clogged piece of foam and go finish... when everyone else is blown up, clogged up, or slow...

[uchi]

good to know, ill look into one of them once im ready to upgrade. the snorkel that came on these things from factory is actually quite impressive. i remember going into a ditch, let me be more clear, we entered an area called mosquito trail. this is the area that ive seen trucks on 44 inch tires sunk up to their windows and that was during the dry season. so we decided to run around there on our quads. avoided everything and just got muddy. problem is to get out i had to go through a ditch. having no reverse sucks. so i drop the front tires into the ditch, and slowly slide into it until my headlights are under water and the controls are covered too, i clicked second and got on her hard, seat was under water once i fully dropped in. i got out, but was completely covered. i pulled the lid off the air box and it was dry inside. completely dry, so the snorkel did its job. right now i drilled the lid to let a bit more air in and to compensate for its slightly rich tune.

[sheweezy]

Kinda changing the subject...but it seems all anyone has mentioned it Uni and K&N...just going to throw this out there, DT1 makes an excellent filter, so nice Curtis Sparks orders there elements for his filter...IF YOU WISH to run a foam filter, since it seems everyone has a different opinion on which element to run, you might wanna look into a DT1...pretty sweet filter, cheaper or same price as Uni, dyno'd higher than Uni, even tho it was fractional..James Stewart runs DT1 on his race bikes and whether you like him or not him and his bikes are super fast

[MtnEX]

Yeah, the thing will really spoil you when you go to make a move to another quad.

I ride mine a lot in trails, through water, mudholes, etc... and never have to worry about it.

It sucks cleaner air too in dry weather.


Myself, I have never went out of my way to try to rejet a little to see if it would make more power without the lid because I never noticed much difference with it on and off.

I bet it makes a difference when it gets real hot due to the hot air though. I just don't know and don't figure it matters enough to give up the lid.

[uchi]

my pred was dyno tuned by the previous owner and it ran fine the way it was. i drilled a few holes in the lid and it instantly ran like crap, crack the throttle and it would throw fire out the exhaust and make a hell of a noise. it wasnt happy. my 400 on the other hand must have been jetted al ittle rich and likes the drilled lid.

[MtnEX]

The Predator probably was pretty restricted with the lid on.

I had a Z400 here that was that way.
Removing the lid on it was worth it.

[CJM]

Engine mods and the lid being off help quite a bit. Obviously more airflows needed if you have higher comp, larger bore, etc. Im running a uni and the outwears lid where you cut your stock lid and put the outwears on.

With the lid on I know Im down on power slightly, I can still feel it tho. Nothing insane but enough to notice.

If I had a stock machine I would see removing the lid as rather pointless, since you dont have the rest of the supporting mods needed for more air.

[uchi]

agreed that thing was likely very restricted with the lid on. if i still had it id jet it to run with a modded lid. that 530 was a monster regardless. third and fourth gear sideways across the park near my house bouncing off the limiter, no traction at all, lol

[slightlybent47]

It’s funny to see new and old riders that want every once of HP they can get in order to go faster, only to over look one thing that has more to do with going fast then anything else and that’s tires.
I can tell the deference in new rubber and tires that are even just a little bit worn.
I can trash a brand new set of tires in one weekend on a hard blue grooved track. What I mean is the square edge on all the knobs are rounded off, and that little bit will slow you down. It still has plenty of knob left but you’d be surprised at how much that affects how fast you are.

[MtnEX]

Yep, I'm turning my tires around on my 450 saturday to race them Sunday.

They'll be toast after that... but when I tell people that they are like WTF?... All kinds of tread left... yep that is true but they are ITP's and are no longer sharp and the small sipes will also be gone too.

[uchi]

agreed, the tires on the pred started out good and new but didnt last too long. not with the aggressive nature of that thing. funny thing is the kid i sold it to rode it, touched the throttle twice and it got hairy on him both times. pulled up to me, kinda pale and expressionless, said yeah its fast and took it. not even two weeks later he had it listed on kijiji saying it was too fast for him, lol.

i ended up running a set of maxxis zillas on the back of my 400. they wear fast on the road but weve been doing lots of hill climbing and these offer much needed grip for that. great for muddy trails aswell. not so good in the snow

[uchi]

just for fun heres a shot of them

http://img.photobucket.com/albums/v96/turbocav/DSC_4812.jpg

http://img.photobucket.com/albums/v96/turbocav/DSC_4814.jpg

[BenHonda400ex]

Originally posted by 426kidz
I want a uni, but never had a prob with my k&n just like the uni better Haha I like the Uni because it's cheaper :D