Fitting a K&N filter

[cockneyjanner]

I have bought a K&N Air filter and plan to fit it asap. Are there any pitfalls in fitting one? Or has anyone got any top tips which might help? I haven’t ever removed the tank before, but am hoping that it’s as straightforward as the Jap bikes that I’ve had before.

Any help gratefully received.

 

[Slowdown]

Tank off on a 1200 is easy peasey - just remember to have it empty, not full when you lift it You don't need to remove the front 2 bolts for the tank - just loosen them.


K&N filters get mixed reviews - some like the potential power gains and reduction in flat spot and some dislike the additional amount of dirt/particulate they allow through.

 

[swissrob]

why do u want to remove the tank??

air filter is just the side panel!

 

[Nice 'n' Fat]

Remove fuel tank? Are you sure? I just undid the trim fasteners on the offside of my GSA and slid the intake pipe off

 

[AndyW]

 

[cockneyjanner]

Blimey, I'm glad I asked!

Has anyone done this job on a non-adventure model?

 

[Nice 'n' Fat]

It's as you see in the photo. The offside tank covers come off exposing what you see there. The air intake snorkal runs from the filter box on the left towards the front and finishes just below the fuel pump (the white circle in the photo with the pipes coming out of it) The air intake is held onto the filter box with two expandable plastic clips top & bottom. Remove the clips then carefully slide the air intake away from the bike exposing the paper filter element. If the filter is reletively clean then I would suggest you keep it incase you want to put the K&N on another GS/GSA in which case you can swap it back onto the bike

 

[cockneyjanner]

Thanks for your help guys

 

[Steptoe]

K&N, such a huge power gain and numorous other benefits it makes you wonder why BMW don't fit them or a similier filter from new

 

[Mikefirefighter]

I already had a decated exhaust and a Beowulf end can.
Im worried that if I fit a K&N Ill run into the much talked about lean burn problem.

I run the standard ECU funds dont allow me to upgrade it.

 

[wadham]

K&N filters do nothing or nearly nothing to improve performance of a BMW Boxer engine.

How do I know - been there got the 'T' shirt - had it dyno-ed by good performance tuner who said don't bother its a waste of money.

The results of the power run proved it and showed that the engine was running so lean that it might damage itself.

If you do any mods to the newer 1200 boxer engines take it to a reputable tuner with a dyno and see for yourself how lean they are running.

Myself, I have just changed the header pipes and kept the OEM end can. Works just fine and gives a good deep exhaust tone.

your choice.

 

[GoldenGS]

Hi Wadham
I'd be interested in seeing your set-up, would like to get rid of the sewing machine noise at standstill and get a bit more midrange. I'm in Reading, are you near?
Mark

 

[wadham]

Hi Wadham
I'd be interested in seeing your set-up, would like to get rid of the sewing machine noise at standstill and get a bit more midrange. I'm in Reading, are you near?
Mark

I have fitted BOS header pipes to an 09 GSA and kept the OEM end can. Thats all really. I intend to get it dyno-ed once it has done 4000 miles and will publish comparison to 08 GSA on here.

Yes it feels much better in midrange pull (tbc by dyno of course).

Noise is louder and deeper. I like it better than a Remus end can which is to boomy and harsh.

PM me and you can come over to hear it.

 

[Red King]

I had a K&N filter for 10,000 kms. I went back to the OEM after consistently finding a lot of crud and dust in the intake behind the filter. Rather than risk damaging the engine, I switched back.
It should be fine so long as you very regularly clean the filter especially if you travel in the wet and in dusty conditions..
I saw no power gain at all, but I did experience some increase in the midrange torque, but very very moderate to be honest. Not worth the hassle.

 

[BiG DoM]

It is critical that you grease the seal as specified when installing and after cleaning. k&n's work great if regularly cleaned, properly oiled and greased to give proper s4eal when fitting.

 

[AndyW]

Silicone grease or vasaline on the seal

Cleaning..........CARE! In actual fact you can keep decreasing the effectiveness of the filter by unnecessary cleaning, they work best once they've been run for a while and only need cleaning up to every 50,000 miles in normal use!!!! Full details and other FAQ's here: http://knfilters.com/faq.htm#4
Applying too much oil is something else people do unwittingly ;-)

 

[Red King]

It wasn't the sealing around the filter that was wrong. The filter was allowing crud to pass unfiltered. See the below link for more info on K&N filters capacity to filter:

http://www.roadkill.com/~davet/moto/air.filters.html

Basically they are designed for higher air flow, but this really only gives better performance when used in conjunction with a racing exhaust system and some retuning. I think without a new exhaust system it may give anywhere from 0-1 hp extra. With a new exhaust system it can give up to 3hp gain. Higher airflow = less filtration = reducing the longetivity of your engine unless you rebuild your engine regularly

 

[AndyW]

.....on the basis of what you say you'd think they'd have gone bust by now?!

K&N has sold more than 30 million washable/reusable performance high-flow air filters since 1969

 

[Red King]

Just posting my own experience and anothers research.. Their filters work fine for bikes in a dry and low dust environment. They haven't worked well for me in the conditions I ride. I am sure they work very well on a sports bike with a full AM exhaust system and retuning... didn't work for me and haven't seen it work for anyone else...

 

[AndyW]

Fair enough.........work well for me, had K&N's on several cars and bikes, my GS does have the benefit of full Remus exhaust, the K&N, PCIII and has been set up on the dyno.......spot the non 'adventure' rider

Interesting real life review on webbikeworld.com referring to an 1150GS.....and reader comments at the bottom, for and against:
http://www.webbikeworld.com/t2/k-n-air-filter/

This is particularly interesting...

One of the interesting features of K&N air filters is that they have a 1,000,000 mile guarantee! Also, K&N claims that original equipment manufacturers are moving away from disposable (i.e. more stuff in the landfills) paper filters. They say “K&N fully expects to become the default standard and supplier for a majority of OEM applications in the not-so-distant future.”

K&N's own blurb: http://www.knfilters.com/filtercharger.htm