K&N Filters - worth it? [Archive]

ManDownUnder

22nd January 2007, 09:52

idleidolidyll

22nd January 2007, 09:55

I've been riding for a long time, never worried about anything other than stock/disposable air filters and I see K&N filters getting a good commentary on a regular basis... so I hit their website and there's nothing I could find that specifically says

10% more power, or 20% less resistance or... whatever. So my question is - what are your experiences/thoughts on them?

I see they can be washed and re-oiled (like a real filter... good!) etc, but

HP Gains to be expected on the RF (110hp at the back wheel)
Price?
Availability?

Problems?

Cheers

Regardless of any claims for extra power, the fact that they last forever is enough reason to buy them. Basically the price you pay for them is only as much as 2 or 3 standard filters.
HOWEVER: Yes, generally they DO flow more air but unless you are fitting other items and/or rejetting/recalibrating injection map to suit, you may not notice much difference.

The Stranger

22nd January 2007, 09:59

I've been riding for a long time, never worried about anything other than stock/disposable air filters and I see K&N filters getting a good commentary on a regular basis... so I hit their website and there's nothing I could find that specifically says

10% more power, or 20% less resistance or... whatever. So my question is - what are your experiences/thoughts on them?

I see they can be washed and re-oiled (like a real filter... good!) etc, but

HP Gains to be expected on the RF (110hp at the back wheel)
Price?
Availability?

Problems?

Cheers

Ha ha, you really didn't use the search did you?

But despite the vehement negativity I have had quite positive results with them, including improved performance and fuel economy.

Plus they start and look quite reasonable when you consider the MASSIVE cost of a genuine Suzuki filter.

pervert

22nd January 2007, 10:02

How much HP or % you would gain is an unanswerable question. That would all depend on the make/model of vehicle, and how good the factory filter is to start with.

idleidolidyll is right, they are worth it because of their longevity alone. Having only used them on cars I would say they gave a noticable increase in power, although that could always be a placebo effect caused by the increased induction noise they seem to give.

Cajun

22nd January 2007, 10:03

there are other brands also BMC, DNA.

Both good, major reason i see is reuseable and, get a bit better air flow, and couple more hp but most people won't notice the difference, with some bikes it also changes the sound the ram air does make(did on the 600).

But still worth it for small out lay

ManDownUnder

22nd January 2007, 10:05

Cheers guys.

Yes I did use the search and found bugger all - they mentioned the horsepower gains are mentioned under the part number of something - but the part number was there all by it's lonesome on the site (http://www.knfilters.com/search/product.aspx?Prod=SU-9094)

Anyway. It does lead onto the next q - rejetting....

Costs? Benefits if done without the K&N filter change?

I'm a complete newb to this stuff (I just buy 'em and ride 'em) but I have to admit my curiousity has been piqued of late

Crisis management

22nd January 2007, 10:56

Jetting gets into the messy area.....ideally it should only be carried out on a Dyno so that you can see results and adjust for optimum running. Thats not practical due to cost and possibility of mechanical damage to the engine.
Conversely you can buy Dynojet kits in various stages for most bikes so you can match, say, an RF900 with K&N filters & aftermarket pipe with a stage 1 jet kit.

However, what are you trying to achieve? A cheaper (long term) filter or a faster / better performing bike, better fuel economy or???

I would suggest a search of RF900 sites / references for what worked and didn't rather than relying on heresay from owners of different bikes as it is so dependant on the strengths and weakness' of the particular model of bike.

You are probably onto something that will net real gains for you as my experience of Suzuki's has been that they are choked with restrictive airboxes and exhausts and jetted lean. However you may have to change more than the filter element and jetting to make it work.

buellbabe

22nd January 2007, 11:02

Regardless of any claims for extra power, the fact that they last forever is enough reason to buy them. Basically the price you pay for them is only as much as 2 or 3 standard filters.
HOWEVER: Yes, generally they DO flow more air but unless you are fitting other items and/or rejetting/recalibrating injection map to suit, you may not notice much difference.
Totally agree!
And for the record... after having a Vance&Hines can and a K&N filter fitted (plus being mapped on the diagnostic machine cos airflow changed) it was then tested on the Dyno and I had a 10HP gain.

NinjaBoy

22nd January 2007, 11:13

Regardless of any claims for extra power, the fact that they last forever is enough reason to buy them. Basically the price you pay for them is only as much as 2 or 3 standard filters.
HOWEVER: Yes, generally they DO flow more air but unless you are fitting other items and/or rejetting/recalibrating injection map to suit, you may not notice much difference.

Sorry to go off topic... but I'm thinking of fitting a K&N just for the extra life. I do a lot of commuting and the filter does need to changed quite often.

I was wondering whether you need to recalibrate after fitting the filter ? Also I have a Yoshimura end can and I don't think anything was recalibrated after it was fitted.

thanks

Cajun

22nd January 2007, 11:15

ninja boy, nah your bike is FI so no real need.

Motu

22nd January 2007, 11:21

You'll only see claims for K&N's air flow ability,not their ability to filter air - and um,surely that is what an air filter is for? There is a lot of controversy,and the only way to find out if the air filter is filtering air is to check the wear rate of the engine..Obviouisly you can't wait to wear the engine out and compare it to the last engine you wore out - su used oil analisis (UOA) is used.With a K&N there is always an increase in silicon levels,this means fine sand particals are entering the system.Sometimes there are increased levels of lead and iron....bearing and bore wear.But the battle still goes on.

I am using a Green Filter in my Pajero as I put a shit load of kms on it,the Green Filter is far superior to K&N as they use two different sizes of woven fabric,not gauze like K&N.I also made my own foam sock to go over the outside.I've only had it on for 5,000km,but will monitor the intake track for grit.Green Filters claim to filter down to 5 microns....

vifferman

22nd January 2007, 12:05

You'll only see claims for K&N's air flow ability,not their ability to filter air - and um,surely that is what an air filter is for? There is a lot of controversy,and the only way to find out if the air filter is filtering air is to check the wear rate of the engine..Obviouisly you can't wait to wear the engine out and compare it to the last engine you wore out - su used oil analisis (UOA) is used.With a K&N there is always an increase in silicon levels,this means fine sand particals are entering the system.Sometimes there are increased levels of lead and iron....bearing and bore wear.But the battle still goes on.
..
True.
And if you search The Interdweeb properly, you'll find independent tests of K&N filters thatpoint out that they don't perform very well for filtering and don't let that much more air through. It's all HYPE.
They do let some more air through, because they have bigger holes, so let more dirt through too. If they do let more air through, then they'll make the engine run leaner, so retuning will be necessary.

You could do what I've done twice. I was impressed with the Unifilter on my VFR750, and couldn't get one for the VTR1000 (they don't make them), so I cut the filter out of the frame and made my own, use Unifilter foam. I did the same on the VFR800. :Punk:

N4CR

22nd January 2007, 12:51

motu made an interesting point many eons ago. he mentioned why the filter might be a bit better at 'flow' and that it might not be working very thoroughly as a filter... so put the k&n's in and get crap into ya cylinders? that might be the compromise. search it'll come up somewhere on kb.

gah just read the rest of the thread he's beaten me to it.

aderino4

22nd January 2007, 14:08

Do you know who stock the K&N filter in Auckland?

Just finished tearing apart the NSR on the weekend and we found only half of the foam filter left in the airbox. The other half? probably has gone into the cylinder.

Plus I need one for the car.

Motu

22nd January 2007, 14:25

Pioneer Products.

bell

22nd January 2007, 15:43

I remembered this post where Jim2 had mentioned the gains from his DNA filter on the Z750.

...good news front, the new engine cover looks grouse, the rear hugger looks great and will stop the Ohlins getting covered in munt, and the DNA air filter has freed up about 10HP and fixed the fuelling right through the range.

Open the taps at 100km/hr in top and there is no need to change down to overtake now.

rogson

23rd January 2007, 09:24

Don't waste your money on a K&N (or any other fancy brand) filter.
From memory the RF900 filter is a flat rectangular element isn't it?
Buy a rectangular pad of UNI foam filter element (about $20).
Cut it to size/shape. Use the frame of the existing filter if need be to support it or fashion-up a support out of some wire gauze.
Oil it and slot it in.
The foam can be cleaned and reoiled - will last the life of bike.

Oiled foam has as good if not better filtering properties than most other types (after-all they are used universally on dirt bikes), and I suspect it will have less restriction to flow than the stock filter, inwhich case you may need to rejet - but will get a performance gain if you do.

xwhatsit

23rd January 2007, 11:25

Pod. Pod pod pod pod pod. Pod pod pod pod Pod POD!

*whooooooooosh*

vifferman

23rd January 2007, 11:32

Buy a rectangular pad of UNI foam filter element (about $20).
Cut it to size/shape. Use the frame of the existing filter if need be to support it or fashion-up a support out of some wire gauze.
Oil it and slot it in.
The foam can be cleaned and reoiled - will last the life of bike.

That's basically what I said.
But cut the foam just marginally bigger than the frame, and glue it in using hot-melt glue around the edges or silicon sealer (the latter's apparently not recommended if you have a catalytic convertor fitted).
You can still clean and re-oil it, but it stops any crap getting in around the edges. I've done this on two bikes now, and have detailed destructions and pix if anyone's interested.

Fatjim

23rd January 2007, 12:52

And where do we get a $20 pad of unifoam filter material.

vifferman

23rd January 2007, 13:19

And where do we get a $20 pad of unifoam filter material.
From the $20 shop?

Actually, I bought mine from Motomail, a few years ago. If I recall, it was $32. Made a VTR1000 filter and VFR800 filter from it and still have a little left.

Fatjim

23rd January 2007, 13:23

dumb question removed

vifferman

23rd January 2007, 13:41

dumb question removed
Does that mean I have to remove my dumb answer? :spudwhat:

Grahameeboy

23rd January 2007, 13:46

Ha ha, you really didn't use the search did you?

But despite the vehement negativity I have had quite positive results with them, including improved performance and fuel economy.

Plus they start and look quite reasonable when you consider the MASSIVE cost of a genuine Suzuki filter.

Both my RF and SV showed improved performance.

Both had / have TRE's, however, after fitting K/N to SV it now does 103kph at 4,000 rpm instead of 100kph......so I guess that must show extra something..same happened to my RF.

Grahameeboy

23rd January 2007, 13:48

The Stranger

23rd January 2007, 13:49

Both my RF and SV showed improved performance.

Both had / have TRE's, however, after fitting K/N to SV it now does 103kph at 4,000 rpm instead of 100kph......so I guess that must show extra something..same happened to my RF.

Ok, not sure how to respond to this one.
But I'll play it safe and assume this is a piss take though.

ManDownUnder

23rd January 2007, 13:53

Well I bought one... US$39.95 and it should be here in.. about ... 6 - 8 weeks...

Thats a long way down from the quoted NZ$139...

imdying

23rd January 2007, 15:05

Ok, not sure how to respond to this one.
But I'll play it safe and assume this is a piss take though.
Agreed. I wonder if paid extra for the magical gearbox mod though? :dodge:

Grahameeboy

23rd January 2007, 21:01

Ok, not sure how to respond to this one.
But I'll play it safe and assume this is a piss take though.

No it really is true

Lou Girardin

23rd January 2007, 21:31

I won't use a K&N because of analysis results I've seen.
But if 1 extra hp matters, go for it.

xwhatsit

23rd January 2007, 22:56

No it really is true

Lol, wtf? So how did an airfilter change your gearing?

scumdog

23rd January 2007, 23:06

Lol, wtf? So how did an airfilter change your gearing?

It doesn't - it makes his rev-counter read slow.

Shadows

23rd January 2007, 23:41

I've heard that they can be problematic in wet weather. Well, for bikes like mine, anyway, with the air intake sticking out the side and exposed to the elements.

FilthyLuka

24th January 2007, 12:48

The Stranger

24th January 2007, 12:51

i have a question! are you guys talking about pod filters? or slot in replacement filters? either way, can i get one for the ginny? air filter needs replacing soon so might aswell get a mean one!

denis

A pod filter!
With just a few mods more mods, you can pull some mean HP from the ginny - but a pod filter is a good start.

Motu

24th January 2007, 12:56

You will only need a Shuffle 'pod for a GN250.

FilthyLuka

24th January 2007, 12:56

A pod filter!
With just a few mods more mods, you can pull some mean HP from the ginny - but a pod filter is a good start.

the mods so far are... a slashcut shorty pipe (loud mofo), a rejet, Shiny shiny inside bits... thats actually about it... pod filter would be cool though, i suppose i could just take out the airbox and put the pod in where the airbox used to be, no fancy pipes or nuthin. hmm, Does anyone know the diameter of the Ginnies carb air intake?

denden

Crisis management

24th January 2007, 13:02

How about one of them Screamin Eagle filters side mounted like real bikes.....now that would get some attention (and go with the slash cut pipe):sick:

Bonez

24th January 2007, 16:48

Make you own foam filters up, as suggested, using the existing paper element frame. Cut out the paper element, get some air filtration foam from pararubber( two grades available), cut to shape and glue in place of the paper element. Use appropreiate oil in the foam. Fit to bike and away you go.

I've done three bikes for the replacement cost of an OEM filter so far.

tipper

24th January 2007, 17:11

It doesn't - it makes his rev-counter read slow.

does the reverse work?? if I stuff a hanky down the carb will save me swapping my 14T for a 13T; may have stumbeld onto summat here, like water powered bikes!! :)

dawnrazor

24th January 2007, 18:46

on standard settings a K&N won't make a great difference, but with an aftermaket exhaust system and/or a power commander then yep they are the go...the induction roar gets well tasty as well, the performance gain is really only top end...so hmmmmmm theres my two cents

RM125king

24th January 2007, 20:17

you can get any k and n filter from auckland mpower and sports in kyhber pass but i brought one for my r6 and the quality i thought was crap so i went and brought a DNA one and love it. made the ram air alot louder and it seemed to pull a bit better but that could be all in my head at the time :scratch: