K&N Air Filter

[MikeH]

Does anyone have a K&N air filter fitted? I'm just wondering if it's worth buying one for improved air flow, but can't find any details of improvement in performance. The cost is several times the standard OEM paper cartridge - is it worth it? Also, how often does the filter need to be cleaned and re-oiled?

[lorazepam]

The K&N should last years, just take it out and clean it and re oil it once a year, and that is all you need to do. I dont know if it improves the performance all that much, but it is easier on maintenance. I think it is cheaper in the long run.

[Feedback]

Mine had a K&N in it when I got it so I can't tell you if it made much of a difference. I do know it made a noticeable difference in my Toyota pickup. A friend of mine works for K&N. When I told him I had gotten an RS a while back, he told me they just had one on their dyno doing some tests. They seemed to be impressed with the amount of torque...."never ending" is how I think he put it. And it got even better with a K&N. Not sure if it was an 1100 or 1150.

[lorazepam]

I would be interested to see the data from that dyno run. If he can get it, please post!!!!!

[cat0020]

I've been using one on my 2002 R1150RS since 6000 miles, now at 25800 miles, I've only cleaned it once. I can't really tell how much performance difference it made over OEM air filter.

[Rando]

I have a K&N and like it. It will save money in the long run. One thing, I was always told to clean it (solvent and recharge with oil) every 25K or so. The more fine particles it picks up, the better the filtration. I do check it once a year for dead bugs and other major debris.

[Motogirl]

I installed one a few months ago, after reading some prior posts on the brand. I''d like to see dyno results, too. Not that I don't believe them but I didn't notice any difference. Lets face it, how much should we expect for $40 ;)

[breyfogle]

In my opinion, the only benefit of a K&N filter is cost. You will never have to buy another filter. If the cost of BMW air filters is a concern to you, buy the K&N but don't expect any noticable performance gain (or loss).

[Joisey]

After I installed the Z-Technik exhaust last year I noticed that I lost a bit of power on the bottom end (under 3500rpm), but the bike seemed to have more giddyup at the upper rev ranges than with the stock exhaust.

Two weeks ago I installed a K&N filter and now the bike seems to have regained much of the bottom end torque lost with the exhaust conversion. This is just a seat of the pants evaluation, of course, but it was noticeable.

On the other hand, it could also just be my subconscious trying to justifying the cost of the new exhaust and filter... :dunno:

YMMV.

[soren]

K&N air filters are, in a word, snake oil.

See http://www.monmouth.com/~deilenberger/R1100R/index.htm .

When I bought my RS, it had a K&N air filter installed. I noticed that the air intake ducts where condensed oil from the crankcase breather tends to collect had deposits of a slightly coarse texture. I wonder if that might be due to poorer filtering or perhaps simply because the rubber lips on the K&N don't fit nearly as tightly around the fittings in the air box as a stock air filter even though the rubber on the K&N filter seemed to be in good condition.

I also think the economy argument is false. To keep a K&N filter in good condition, you need their special filter oil, which isn't exactly cheap. A stock air filter costs no more than an oil filter. If you really want to save money on air filters, just take it out every once in a while and shake off the dust. It will easily last much longer than the nominal replacement interval.

If anyone wants my K&N filter, they can have it..

[Rob O]

Well, for the other side of the story, read this:

http://www.motorcycledaily.com/21september04_kandnfilter.htm

I know, I know, it isn't an RS, but dynos don't lie and if the ST can get six ponies from a K&N, we should be able to get a few too, don't you think? YMMV, of course.

Rob

[soren]

Quoting from http://www.motorcycledaily.com/21september04_kandnfilter.htm:

"As you can see in the picture above, K&N's replacement filter for the ST1300 (part # HA-1302) appears to be quite a bit less restrictive than it's OEM Honda counterpart. In fact, according to K&N Product Engineer Charlie Tissen, HA-1302 flows approximately 15% more than the factory Honda filter. We were curious to see if this increase in flow translated to increased wheel horsepower."

Uh huh..

"Before installing the filter, Tissen made several dyno runs with the stock configuration to get a baseline for comparison."

Uh huh.. :-)

[gezerbike]

Most independent tests show the K & N has little if no effect on improving performence on fuel injected bikes run by a computer ( Motronic ). I do have one on my '97 F 650 ( with carbs ) and I do think it is a positive improvement here. You guys who have them be careful when you clean and re-oil them ....too much oil on them is not a good thing

[Feedback]

K&N air filters are, in a word, snake oil.



If anyone wants my K&N filter, they can have it..
I'll take it!!! Thanks!!!

[bryanotter]

I fitted a K&N filter around 2000 miles ago. I can confirm that I did feel a big difference. The bike ran smoother and definately had more torque. It accelerated better....and in fact felt like a totaly different bike. :yo:

[MikeH]

Thanks to all for the opinions.

On the off chance that it will give any kind of improvement in breathing , I'll fit one. I didn't expect that it would result in any significant power increase but you never know.

[Harpoon]

I put a K&N filter into my 2004 R1150RT at 8500 miles and noticed that the idle was smoother and acceleration although not noticeable faster was also smoother. The most significant difference is in engine breaking where it seems that letting off on the throttle slows the bike more gradually and the intermittent grab that I had off throttle at about 1800 RPM in third gear into corners is nearly not noticeable. Note that the filter was added about 500 miles after I had just done valve clearances so the bike was already pretty smooth.

I'd recommend the filter if a bit more refinement is the goal.

[scottfarm]

A K & N is not as good as your stock filter and worse for your engine. It does not filter the dirt as well. The oil from the k and n collects on your butterflies on the trottle bodies which in turn collects the unfiltered dirt causing them to stick open at idle. They tested this engine with no filter at all installed and it made no difference on the dyno. If you think it gives you more performance, you may want to try some slick 50 and one of those turbines to put in your air breather to get you 25% more gas milage.

[lorazepam]

I have never used slick 50 for a performance boost, just for added protection of the moving parts. If you check the package, it has a milspec for engine protection, not for performance boosting. In order to get the milspec, it has to do what is claimed, they just cant put it on the package.

Putting on GS tubes will increase midrange performance, not one of those goofy turbine thingies but it will hurt your top speed when hitting a long straight on the track.

dont forget split fire spark plugs, or even the stupid platimum plus 2 they put in the bike from the factory. Electricity follows the path of least resistance, and that wouldnt include using both ground electrodes at the same time.

[rdfarr]

"Snake oil." Exactly. Only an impartial dyno knows. Here's a possible test: Have a friend change out the K&N filter with stock for one day of the week, not telling which day. At the end of the week, see if you could tell what day it was. Which day did you feel the loss of power and smoothness? I'm pretty sure that you wouldn't have a clue.
Also, regarding milspecs (i.e., Military Specifications): Complying with the milspec for engine oil gets you... engine oil.
All that being said, if you like or trust a particular "performance enhancing" product, go ahead and use it. Who knows? - It might not hurt and could even possibly help.

[lorazepam]

The milspec for slick 50 is for anti friction metal coating, not engine oil. I use the K&N filter because it lasts longer than stock and doesnt require to be changed as often. I havent noticed any oil getting into the injectors, though if I over oiled it, I guess that could happen. It can happen if you overfill the oil as well.