I have a '99 SP500, and it started smoking just a little on start-up, and a real light haze upon opening the throttle. So, I checked the air filter, which is a K&N, and looked inside the plastic tube between the carb and air box, and found some dirt in it. A couple months ago, I sank my bike in water over the handlebars, and the air box filled with water. I think that this must have pushed some dirt through the filter, and this is what I was seeing. I took the tube out, cleaned it, and put it back on the bike. I reinstalled the K&N. What I'm wondering is if anybody has had any problems with dust/dirt getting past their K&N. After sinking my bike, I cleaned and reoiled the filter. If anybody has had any experiences with K&N, please respond. Thanks in advance!!!!

 

I have heard on this forum that K & N's let more dirt in than the stock filters. The theory made sence to me at the time however I cant remember it. I have alway been I little skeptical about something letting in more air not letting in more of everything else.

 

Well here is what i know about K&N filters

First off i well tell you im in the oil industry so hate me now if you wish hehe. Now to the point at hand K&N filters deliver more airflow in some aplications in outhers it is the same or only slightly better then stock. So now the test. Now I have performed this test myself and know of 2 outhers that have tried it. Step 1 Have your Cars oil analized afer a oil change. 2 Buy a K&N filter and run it for 3k then change oil and analize again. 3 reinstall a clean oem filter and re analize oil after 3K. If your results are the same as mine you will see that they say Air filter needs replacement only if you are running the K&N filter. Strange but true More air = more dirt .

 

A K&N filter is for bored out machines and will be worse than stock if your ride is not bored. The best filter is Uni and Moose

 

PolarisMan,

I appreciate your attempt to help, however, I disagree with you about K&N filters being for bored machines. Show me anywhere that it says that. Why does K&N have on the box that they meet new car warranties? Why don't they put on there that they meet rebuilt engine warranties. All that a bore job does is increase cc's, like the difference between a 400cc machine and a 500cc machine. Are you trying to tell me that the filter knows the difference between a smaller displacement engine and a larger displacement engine? I doubt it. Again, thanks for trying, but please try to give facts and real-world experience.

 

No not that i know of, the K&N filter cnat tell the difference. But however it does put more power to the engine. Therefore engines that are bored out will see a better increase in power compared to a stock machine.

 

PolarisMan

I would like to get an explanation of how this works. A K&N simply provides increased airflow to the engine, which increases the power of the engine. How would a bored out engine get an increase in horsepower out of K&N greater than a stock engine would. I would like to see the data from the test you are arriving at this theory from. I'm definitely not an expert on horsepower gains, so if you have good sound data to support your theory, I would be interested in seeing it.

 

walexa,
I am not sure if the K&N filters as well as a stock filter. I think it should even though other say "more air" "more dirt" The K&N allows more air flow due to the design and filtration method. The cotton mesh soaked in K&N filter oil should do an ample job of filtering the air. If it is installed properly and your intake boots are in good shape, I don't see how dirt that is visible to the eye could have gotten in? If the filter did a poor job of cleaning the air, the manufacturers would not warranty their machines with these filters installed. I would look for a problem other than the K&N.

Also, you should always put a little grease around the filter where it secures to the intake to make sure you have a good seal.

Good luck.

Greg

 

Greg,
I put clean grease on the inside rim of my filter every time I remove it, but thanks for the advice. I really don't see how any dirt can be getting by the K&N in the quantity that I saw, but I don't know if the water I went through washed that much dirt through either. I'm going to the dealership this afternoon, and I'm going to get a new factory filter for it and run it for a while. What filter do you run in your bike? The only real downside to the paper element is that if you ever get it soaked, it's no good and you pretty much need to leave your bike until you can get a replacement. I just hope I haven't done any major engine damage yet. The bike still starts really quick, and smokes on startup like most Hondas that I see. Then, if you look real close, you can see a real light haze of bluish smoke come out when you rev it up. It's hardly noticable, but being the worry-wart I am about my bike, it bothers me. I'm definitely not going to tear the engine down and rebuild it, because if it had lost any real compression, it wouldn't start so easy(I think). Anyway, do you have any other advise other than doing a compression check?

 

PolarisMan,
I can tell you really know your stuff!!!