Please, stop putting K&N filters in your bikes

[kuksul08]

I couldn't tell you how many bikes I've owned that have had K&N air filters installed by previous owners. Okay, it's actually three, but that's enough to warrant this thread. Friends of mine have had similar experiences as well.


Behind each of those air filters was a layer of grit in the airbox. The damn things do a terrible job of actually filtering air. Hold one up to the light - what do you see? Light! Those are gaps that dirt can pass right through, straight onto your valves, onto your cylinder walls, and the rest is history.


So seriously, stop putting this junk on your bikes unless you are running a race team, need every ounce of horsepower possible, and don't mind rebuilding your engine after every race. Stick to OEM or equivalent paper or oiled, multi-density foam filters for your street bikes.

 

[HeatXfer]

It's an oldie but a goodie:

K&N Filter Review: OEM is better

 

[Schnellbandit]

opcorn

 

[strictlyJDM]

What oil do you run in your bike?

 

[madsen203]

Add to the fact that it sucks in the oil from the filter. This is especially a problem on cars with MAF that get gunked up from the oil.

OEM for the win.

 

[two wheel tramp]

Don't tell me what to do!

 

[moto-rama]

The idea that anyone actually washes their filter is ridiculous, too.

Nobody does that.

 

[Whammy]

ur not the boss of me.
ohh snap just discovered a K&N on the bike.
Errr uhhhh i'll change it out when I get a chance.

 

[Butch]

awesome stuff. Like tires, the better an air filter works, the more it costs.
this

Every filter is initially tested at 350 CFM and the Initial Restriction or differential pressure across the filter is recorded in IN-H20 (Inches of Water). The filter is then tested by feeding test dust at a nominal rate of 9.8 grams per minute with a constant airflow of 350 CFM. The test is continued until the flow restriction exceeds the Initial Restriction + 10 IN-H20.

I'll comment more later.

 

[kuksul08]

Don't tell me what to do!

ur not the boss of me.
ohh snap just discovered a K&N on the bike.
Errr uhhhh i'll change it out when I get a chance.

I'm yer real dad!

 

[JesasaurusRex]

agree, they're more trouble than they're worth

 

[Frame Maker]

So seriously, stop putting this junk on your bikes... Stick to OEM...

What do you suggest for home built bikes that don't have an "OEM" filter?

[/url]20171008_181633 by andbike, on Flickr[/IMG]

 

[Butch]

Velocity Stacks, you pussies.

 

[Frame Maker]

Velocity Stacks, you pussies.

:rofl

 

[two wheel tramp]

I'm yer real dad!

:laughing

 

[kuksul08]

What do you suggest for home built bikes that don't have an "OEM" filter?

Then at least have the courtesy of putting a multi stage Uni filter pod to protect your hard work.

 

[HadesOmega]

I use Uni filters on all my bikes that see dirt. They filter really good, always clean on the other side but yeah I clean it often because of the dirty conditions. I can make em last longer with filter skins. One thing I don't like about K&N filter is the rubber seal gets old and hard after a while and they don't seal as well.

I use K&N filters on my cars and they work pretty well, save money after a while too. The important thing is to not oil them too much.

 

[Rumbo Sur]

My first experience with K&N air filters was on my '81 BMW R100RS. Real nice bike, was a sort of "show bike" for San Jose BMW. An important BMW dealership in those years. Many many mods and additions.

I bought it used, came with K&N on the Del 'Ortos. Not pods, just a K&N in stock position (pancake style filter in air box that handled both cylinders)

I knew nothing about K&N then (1987) but soon discovered A LOT of grit in those fancy Del Orto carbs. It ruined them. Both had serious worn parts on this 30K mile bike. The top end was in bad shape too. and my K&N was clean and well oiled.

Very low miles for a BMW boxer to show wear. I never knew it was the
K&N until a BMW mechanic friend clued me in. Had to do a valve job and re-ring. He worked at the original BCW.

Some DR650 owners run K & N filters despite knowing how poorly they filter. The solution (sort of) some employ is to put an oiled "pre filter" over the
K&N like the Filter Skin product. Change every 1000 miles, sooner if riding off road in serious dust ... or simply get a "real" filter like my fav, Twin Air.

As mentioned, the K&N does breath well ... but to me, not even close to being worth it. Even on the street, you just can't believe how much fine grit gets into your engine running a K&N. I rode that BMW cross country ... twice ... so had enough time to observe. No off road.

Car guys like them, not ideal for motorcycles in my limited experience.

 

[FreeRyde]

DR650 the best!!!

 

[planegray]

I use Uni filters on all my bikes that see dirt. They filter really good, always clean on the other side but yeah I clean it often because of the dirty conditions. I can make em last longer with filter skins. One thing I don't like about K&N filter is the rubber seal gets old and hard after a while and they don't seal as well.

I use K&N filters on my cars and they work pretty well, save money after a while too. The important thing is to not oil them too much.

Heh, he said "old and hard" :banana