Thread: K&N air filter

Other than fact the K&N can be reused .Is it really all that much better Than factory as far as performance (air flow=HP)

I see many here have changed I had one on a car It sounded good but I don't think real performance gain.

FLOW COMPARISON CHART
Foam	Amsoil LT-31;	376 CFM
K&N (used)	(42,000 miles) K&N E-1500	463CFM
Paper	AC A348C; Fram CA326; Hastings AC-145; K-Mart KA-12; Motorcraft FA-71R	508 CFM
K&N Filtercharger ®	K&N E-1500	887 CFM
TEST NOTE #1: All air filter elements were flow tested at .3" H20 (water) restriction and then converted to 11/2" H20 restriction by using the square law formula. TEST NOTE #2: All elements tested were of equal size (12" od x 31/2" H) and were specified by their respective manufacturer for the same application.

Heavy got an answer for everything....

On a serious note. I used a K&N for some time with great results. I am now using a BMC race filter.

Just remember more air in has to be burned off and needs more room to get out.

Bolt on exhaust no big deal but start messing with the amount of air that the sensor sees and you'll need to tune. Just my opinion

Agreed, just calling it out.

Its sad that ive had my busa for a few months now and I am still running a paper filter...

What about B&M?

i also use the BCM race filter,never used k&n

Ok I see BCM race filter and street at present on their web site These seem to be better than the K&N . Like I said I had a K&N and except for sound when you nailed it I never saw any difference.
I am stock except for the double bubble gopro ATRE I installed last month. Bike runs smoother but lost 2MPG.
I will be doing slip ons down the road. Those will be the R-22's
I don't want to remap or add power commander at this time.
So now will I be better of with the street or race filter. Is their that much difference. .
Please forgive me I have went from Model T to a Ferrari when I bought my bike new in 07. I said I was going to leave it alone and I have been good but Its that double bubble screen I bought fault. Once you start can't stop.

Help me understand what you are trying to do here?
You honestly cannot buy a bike like the busa and start tracking gas mileage, right?

If you are going with slip ons and no tune, with a TRE then I can tell you it wont mater what filter you buy because those mods wont be making huge gains.

So whats your end result?

I don't expect huge results. I was just looking at picking up a small improvement I track milage for fun I mean it on the computer.
I am unable to ride any distance any more since the car wreck I can do about 60 miles a day. With a hour break at 30miles. Sometimes I get home I can hardly get off . I didn't ride at all in 2009 It just sit and was started. I been riding since I was 16 (305SuperHawk) I am now 64. Clock almost stopped at 62 . I love to ride and want to do limited little mods More just to do than anything. I have never owned a stock car or bike . I will never run on a drag strip and I won't feel safe trying to find red line in 6th any more . But I will ride as long as I am able . I try to ride a little every day weather permitting .

ahhh ok that helps, its hard to help some people because they have no idea what they want to do and everyday is something different. *cough* bigchick *cough*

anyway, MPG is changed by soooo many things, riding posture, road lay out, cruising gear, passenger weight, and so on... so 5 MPG here and there is really trivial.

Fighting comfort seems to be the main focus, so I'd say look at a new seat and bars. Moving the bars back will reduce the forward lean and take some stress off of your back... changing the seat will not only reduce the bump impact on your spine but also help the riding position... I like a low cut seat that I am sitting in like a saddle. Throttle locks, like a throttlemeister is a fantastic improvement because you can relax and sit up when needed.

You'd have to find what works best for you.

Now for performance, I'd say bolt/slip ons, remove the pair system, keep the TRE, change the sprockets (down a couple teeth) for low end, and go with a PC and mild tune. That will be more than enough to get you in trouble while putting the local ricer in his place and saving moderate gas mileage.

biggest bang for the buck.......... stainless steel brake(&clutch) lines + "HH" brake pads
This is a MOD that you will feel in the seat of the pants.

*HH pads will make some noise nothing is wrong with your rotors.

Originally Posted by michael t

Other than fact the K&N can be reused .Is it really all that much better Than factory as far as performance (air flow=HP)

I see many here have changed I had one on a car It sounded good but I don't think real performance gain.

I can say that K&N is a high flow air filter...and reusable plus washable but nothing can change the power of a new replacement filters.. Based on the reviews I read about it, K & N air Filter consists of 4 layers of cotton gauze between 2 layers of metal screen. Cotton is much less restrictive than paper elements and is oil impregnated to capture the tiniest dust particles while allowing air to flow freely.

That graph is a bunch of miss leading bull shit. Maybe I dont know how to read it but it sure looks like the K&N provides twice as much air as the other filters which should translate into double the horsepower. you would be lucky to see a 5 hp gain with a K&N. In addition you have failed to mention that K&N filters generally only filter about 3-15% of the particals that paper filters catch. Unless your running on dustly gravel roads the K&N is useless in my opinion. If you need power that badly just run without an airfilter becuase the K&N isnt catching any of the small suspended particals anyways.

Just because a filter has double the air flow does not mean that you should have double the power. You need to remember that you motor has to deal with that air flow. Yes more air is a good thing but twice the air does not mean twice the power. As far as filtering goes, K&N filter particulate just fine. The only time they are not a great idea is in fine powdery dust time situations. If you keep it oiled and clean at regular intervals you should never have a problem with dirt in you motor or throttle bodies. My bike spent the first 12,000 miles of it's life breathing through a K&N filter and when I replaced it with a BMC I checked the throttle bodies and they were just as clean as they were when new. It all comes down to how well or often you maintain your bike.

Man, maybe a basic understanding of how engines work would be nice before commenting on a thread like this. A free flowing air filter DOES NOT PROVIDE MORE AIR TO YOUR ENGINE. It that was the case, people would just be ditching the air filter all together.

Yes I know but look at what the graph is stating. First off the graph displays CFM With 5.5 in of H2O pressure (.2 psi) loss. It should really show the pressure loss at what ever CFM of air is required for the busa to make make max HP. Standard fuels require .11lb/min/hp. So the Busa probably requires about 19.8 lb/min to make 180 hp. That is about 256 CFM.

So right off the bat this graph doesnt really apply to us.

Secondly it is only .2 PSI. Atmospheric preassure is 14.7 psi so going from 14.7 to 14.5 is a 1.38% loss in density which directly relates to a 1.38% loss in horse power or 2.5 hp from going from filtered to unfiltered. Since pressure loss is based of the flow speed squared and this much air is not needed pressure losses would be significatly less. If your running a 30 psi boost set up your really looking at a 44.7 psi to 44.5 psi loss or about .45% loss.

I do have to appoligise as upon re-reading the below link K&N filters did remove 96.7% of dust. It not too shabby and given moderately less pressure drops I can see why some people would chose to use a K&N filter

Finally see the link on the efectivness of K&N filters and let me know what you think

Yes it is for trucks but it is a lot more conclusive then that graph.
http://home.roadrunner.com/~jbplock/ISO5011/SPICER.htm

Originally Posted by PhilipCruz

I can say that K&N is a high flow air filter...and reusable plus washable but nothing can change the power of a new replacement filters.. Based on the reviews I read about it, K & N air Filter consists of 4 layers of cotton gauze between 2 layers of metal screen. Cotton is much less restrictive than paper elements and is oil impregnated to capture the tiniest dust particles while allowing air to flow freely.

Im ashamed of what I post... ...anyway thanks for the technical explanation...

Originally Posted by ckholloway

Just because a filter has double the air flow does not mean that you should have double the power. You need to remember that you motor has to deal with that air flow. Yes more air is a good thing but twice the air does not mean twice the power. As far as filtering goes, K&N filter particulate just fine. The only time they are not a great idea is in fine powdery dust time situations. If you keep it oiled and clean at regular intervals you should never have a problem with dirt in you motor or throttle bodies. My bike spent the first 12,000 miles of it's life breathing through a K&N filter and when I replaced it with a BMC I checked the throttle bodies and they were just as clean as they were when new. It all comes down to how well or often you maintain your bike.

I couldnt have said it better myself.