I have a 1985 K100 that I would like to convert the airbox system to 4 K$N cone filters but where do I mount the air temperature sensor for the injection? And are there any other modifications that I would have to address? I am making a reasonable cafe bike out of it and want to take off all that I can.

You can`t put on four small KN`s in combination with the L-Jetronic FI since you also need to have the AFM mounted.

But I`ve seen examples with a bigger KN filter connected at the AFM inlet.

But why bother, you would have a much cleaner look with the OEM filter housing.

I use a K&N filter in the stock K100 airbox, works very well and I doubt I would see a difference even if I could fit 4 filters.

my $0.02..

rwiley111 wrote:I have a 1985 K100 that I would like to convert the airbox system to 4 K$N cone filters but where do I mount the air temperature sensor for the injection? And are there any other modifications that I would have to address? I am making a reasonable cafe bike out of it and want to take off all that I can.

This required inconvenience (to what you're imagining) is inside the airbox. Whack an appropriately sized air filter onto the intake end of it, work out how to mount it so it is relatively free of vibration and stable, connect airtight tubes to it and to the TBs, and you're golden. It can be done but it requires no small amount of fabrication.

The hugely respected Tom Cutter of Rubber Chicken Racing makes his living fixing BMW bikes he has been quite scathing of alternative filters including the brand you are considering, pointing out his actual experiences of seeing the dirt that gets through them deposited inside the intake system after the filter. With the standard air filtration he states he does not see the dirt. I have also seen dyno tests of standard versus these aftermarket filters and there is no difference in performance. If you are doing it for appearance and don't mind the abrasive dust entering the engine that is fine but if it is performance you are aiming at IMHO I don't think they are the route to follow.
Regards,
K-BIKE

After the U.S. military issued orders that its vehicles were not to be fitted with those filters, I thought the market would collapse. It did not, and I am still amazed.

Hi guys

I've heard a few bad things about kn filters. These filters require a liquid coating to trap air particles.
Unfortunately if too much of this liquid is placed on the filter. It often ends up in the inlet manifold and coats everything including the butterfly valves.
You have been warned!!


Cheers

Strange rumblings here. I have used K&N filters in a number of applications, both in auto and bike engines. In turbo,s/charged and naturally aspirated.
I have had good results and have not had any dramas. But as has been stated here if they are not oiled correctly it can lead to problems. I have always used the proper K&N kit for the filters that contains both the cleaner and the oil.

As always forewarned is forearmed i guess.

Am looking in to running the k&n on my bmw.
Don't like the look the of the aix box. I have come up with a few ideas
One beening run k&n off the afm
or running single bell mouth from the air flow meter


http://www.google.co.uk/imgres?q=bmw+k100&start=747&um=1&hl=en&safe=off&client=opera&sa=N&rls=en&channel=suggest&biw=1333&bih=630&addh=36&tbm=isch&tbnid=Juuz8CuweZjGMM:&imgrefurl=http://www.roelscheffers.nl/%3Fp%3D1110&docid=gNIscOsjDyRJpM&imgurl=http://roelscheffers.nl/storage/BMW/bmw_rs09/Scheffers%252520BMW%252520RS09%2525209.jpg&w=1000&h=668&ei=0x_8T-aqIcql0QWTs7zABw&zoom=1&iact=hc&vpx=546&vpy=98&dur=54&hovh=183&hovw=275&tx=128&ty=63&sig=101048061719647342534&page=33&tbnh=134&tbnw=179&ndsp=24&ved=1t:429,r:14,s:747,i:281

http://k100rt.aforumfree.com/t2736p50-k100rs-streetbike

Luftmeister used to sell a setup to eliminate the airbox and go straight into the AFM.

Picky;





I have done some research and you could buy a turbo blow off flange on ebay and build
your own version of this. The airfilter used is a RU-2450 it has a 1.75" input diameter so
you need a flange to match.

The measurements on the Lufty plate are;

The bolt hole centers on the plate are 71x30mm.
The plate is 93x52mm with a 15 mm high flange,
OD of the flange is 47mm.

My K75 is a 1991 special edition and it came from the factory with a K+N in the original
position but I'd like to try the airbox delete myself!