Bike mechanic did not recommend K&N air filter?

[paturoa]

I took the strom in for a valve shim check and plug change on Monday morning. I gave specific instructions to not do anything else. Good workshop response was to quizz me on some other stuff (which I said no to) including an air filter change while they were in there. I said that I was going to get a K&N.

Later that day when I picked up the bike the mech had obviously been talking to the person that I talked to that morning (another good sign!), and said that I shouldn't get a K&N as the paper based filters are much better, and that in his experience K&Ns let fine dust particles through and ferk the motor.

I've not heard this before, what say you bunch of keyboard mechanics?

[Madness]

On a bike-specific forum that I frequent the members overwhelmingly rate BMC air filters over K+N. Fitment is one of the reasons but the K+N doesn't offer anywhere near the performance gains the BMC do on dyno tests.

[dogsnbikes]

Yes have been told that in the past and seen difference compared to other filters....

I use Pipercross filters and don't get the dirt on the inside of the filter like I use to on the K&N Filters

[paturoa]

On a bike-specific forum that I frequent the members overwhelmingly rate BMC air filters over K+N. Fitment is one of the reasons but the K+N doesn't offer anywhere near the performance gains the BMC do on dyno tests.

This was more about not stopping the dust rather than performance / dyno.

[paturoa]

Yes have been told that in the past and seen difference compared to other filters....

I use Pipercross filters and don't get the dirt on the inside of the filter like I use to on the K&N Filters

Pipercross - Not heard of them before, I'm off to google that. Is there a local supplier?

[Madness]

This was more about not stopping the dust rather than performance / dyno.

Sure, maybe it suggests that there are other options out there.

Still got the couch?

[steve_t]

I used to use K&N in my cars but I've had multiple issues with oil getting through and on to the MAF sensor. I've gone back to paper until such time as the new car gets a MAFless tune :msn-wink:
No such issue with bikes. Filtration vs flow is always going to be a trade off. I guess the question is whether the really fine particles that get through are going to do any damage over time, eg to injectors, or if they'll just get vapourised in the combustion process or pass through. I'd expect that if there was a proven link between K&N filters and engine damage, the US guys would have sued the pants off of K&N ages ago.

[paturoa]

Sure, maybe it suggests that there are other options out there.

Still got the couch?

yeah, you want them??

http://www.kiwibiker.co.nz/forums/showthread.php/148985-Free-to-a-good-home-two-man-cave-chairs

[paturoa]

I'd expect that if there was a proven link between K&N filters and engine damage, the US guys would have sued the pants off of K&N ages ago.

I've just been reading the manufacture's sites (dicing with BDOTGNZA with that apost'fe) and 2 of the above brands said better than OEM paper. I'd imagine that a nice clean cotton washable freshly oiled could be.

The question for the thread / me is that a real world nz mechanic volunteered with no benefit to himself what he has seen and said don't.

[Madness]

yeah, you want them??

Nah, thanks. I actually lied about getting rid of mine to the carload of islanders. It's still here and is smelling more like a dogs arsehole every day.

[paturoa]

Nah, thanks. I actually lied about getting rid of mine to the carload of islanders. It's still here and is smelling more like a dogs arsehole every day.

So you know your couch smells like your dog's arsehole. I'm now worried that you are familiar with the smell of your dog's arse!

[Gremlin]

OK, so the pure simplicity of a filter is to block bad stuff, let good stuff through... Ergo, the more air a filter lets through, the more air gets to the engine etc. Now, the trade off is that it's going to block less stuff right?

So, the question is, how much to block, how much to let through. Many do say that the aftermarket types do let through dust (engines don't like dust of course) however, I have a K&N and the air box behind the filter looks clean and shiny. This was when I pulled the air filter out and had to knock it against the ground to knock all the dirt off it...

Other option is to look at unifilters...

[paturoa]

Other option is to look at unifilters...

More googleing required, unifilters?

EDIT: ah http://www.unifilter.com/

EDIT 2: LOL, their catalogue page shows a number of bike categories, Dirt Bikes, Street Bikes, Vintage Bikes and an entirely separate class of bikes .... Hogs.

EDIT 3: But no Strom filters.

[Teflon]

K&N were fine on the VTR and TLR I had (no dirt in the airbox from memory).. thou for the zx12 I found BMC race filters were better quality.

[pete-blen]

Filter tests... note where the K&N style come
http://www.kiwibiker.co.nz/forums/showthread.php/150820-Air-filter-tests

[paturoa]

Filter tests... note where the K&N style come
http://www.kiwibiker.co.nz/forums/showthread.php/150820-Air-filter-tests

I did a search before posting this thread and didn't find that. Fantastic link there Pete!

As talked about above, less restriction = more dust, and the K&N for that test had the least restriction and most dust.

Follow the link peeps - it is a good read if you like graphs.

[Flip]

Well K&N have been the industry standard for high flow performance air filters for ages.

Problem with mechanics is they will push onto the customer what ever brand they have on the shelf.

I like the washable K&N filters. They get my vote.

[paturoa]

Well K&N have been the industry standard for high flow performance air filters for ages.

Problem with mechanics is they will push onto the customer what ever brand they have on the shelf.

I like the washable K&N filters. They get my vote.

After reading that last thread link from Pete, I'd agree if I was riding a road bike that didn't go near metal roads. It would appear that K&N make filters that have good flow performance cf OEM paper filters. But the compromise is high flow = less filterring of dust.

[SMOKEU]

I've got no problems with my K&N filter. It's been on my bike for about 6,000km according to the receipt the previous owner gave me from a bike mechanic, and I can't see any obvious signs of dirt on the inside of the filter.

[DEATH_INC.]

I've used both K&n and BMC, and even Uni-filter on road bikes. No problems with any of them, tho the uni-filter did get dirty fairly quick. I run a K&n in My 4wd with no issues either.

[sootie]

I've used both K&n and BMC, and even Uni-filter on road bikes. No problems with any of them, tho the uni-filter did get dirty fairly quick. I run a K&n in My 4wd with no issues either.

If a filter gets dirty quite quickly, would that not be a good thing as long as it did not block up?

[paturoa]

I've used both K&n and BMC, and even Uni-filter on road bikes. No problems with any of them, tho the uni-filter did get dirty fairly quick. I run a K&n in My 4wd with no issues either.

Have a look at the article in Petes post above #15, you may change your mind.

[mulletman]

On a 07 GSX1400 i had i put a BMC filter in and had it dyno'ed, 5hp less than stock, stock back in BMC on TM. ( i guess you need some ram air to get the best out of a BMC/K&N )

[Woodman]

I have a K&N on the klr.

It is the only filter I have had that has blocked up to the point of stopping the engine running. This from clean to halfway through the Molesworth on a very dusty ride. The inside of the filter was as clean as a whistle. Never had that happen with a foam filter.

The other thing is, and it may be coincidence but the bike started using a lot of oil not long after installing the K&N. When I pulled the engine down it was very obvious that it had been dusted:weep:

Not really an answer for you but take it as an FYI.

[DEATH_INC.]

Have a look at the article in Petes post above #15, you may change your mind.

Read it many moons ago. The fact remains that I have never had issues with them. My old 4X4 has done 300+k , the 750 had done 65 odd when I sold it (It's still going strong I believe) and both are (were) sweet as. I've never found any dirt on the wrong side of the filters.
On the 4X4, the best thing is the K&N can handle a bit of water...the paper one's couldn't...

[DEATH_INC.]

On a 07 GSX1400 i had i put a BMC filter in and had it dyno'ed, 5hp less than stock, stock back in BMC on TM. ( i guess you need some ram air to get the best out of a BMC/K&N )
Did you re-jet/re-map?