Stock air filter - is it supposed to be 'oiled'?

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birkdale10

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I just bought a K&N filter for my '16 FJR and installed it today. I was surprised at the stock oil filter, but ... should I have a surprise?

The stock filter looks very similar to the K&N. Foam seal on the ends instead of a rubber seal. A metal mesh protector over the paper filter. The manual that came with the bike shows how to clean the filter - shake, rattle and blow.

The big question: Is the stock air filter supposed to be oiled?

 
No...Best advice: Throw that K&N away and buy another paper filter.
Oi! What you said! (ummm...K&N is a paper filter...)

I've been replacing every stock air filter with a K&N on every bike I've owned since my 1971 Penton 125 MX bike. It was a year old when I bought it, and the stock filter was crap, the rings worn and sloppy. Could have been oil... But I put on new rings and the K&N, ran it mercilessly for 5 years, won a couple of trophies, and never replaced the rings again.

I think they 'breathe' better, but I will admit that I may be inveigled by the hype. YMMV - but I've never had a filter problem in half a million miles on a dozen bikes.

 
K&N producing more power due to breathing easier IS pure hype!!

The FJR is, in no way, limited by the amount of air it can get - at least not due to limitations imposed by the filter. A freer-flowing filter (or no filter at all) wouldn't net you a measureable horsepower gain, IMHO.

If the K&N poses less resistance to airflow, it also poses less resistance to fine dirt. Tests have demonstrated that the K&N is less effective for filtration of finer particulates. I believe that the K&N filter medium is oiled cloth (possibly cotton), not paper.

 
No...Best advice: Throw that K&N away and buy another paper filter.
Oi! What you said! (ummm...K&N is a paper filter...)

I've been replacing every stock air filter with a K&N on every bike I've owned since my 1971 Penton 125 MX bike. It was a year old when I bought it, and the stock filter was crap, the rings worn and sloppy. Could have been oil... But I put on new rings and the K&N, ran it mercilessly for 5 years, won a couple of trophies, and never replaced the rings again.

I think they 'breathe' better, but I will admit that I may be inveigled by the hype. YMMV - but I've never had a filter problem in half a million miles on a dozen bikes.
Foam air filters in 1971 were crap. The foam was not engineered to be an air filter, that only came along later. Oh, and purpose made foam air filter oil beats the pants off motor oil on foam.

K&N is not paper, it is cotton. Better than 1971 foam but not 1971 paper.

Way back when, K&N and OE Honda paper filters were about the same price for my 1978 CX500 so I bought K&N. About this time word was getting out about K&N so I followed a friend's advise and smeared a fingerprint of grease inside my airbox, on the clean side. Smeared my finger in the grease again several weeks later and was not happy at the grit I felt. Decided the OE filter wasn't all that dirty in the first place and put it back in. K&N nevermore.

I believe my 1993 Infiniti and 2002 GL1800 OE paper air filters were oiled, or at least treated with something during manufacture. Honda went so far as to instruct, "Do Not Wash."

 
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Back in the old days of carbs before fuel injection became the norm, K&N may have offered some advantage over stock. Of course back then airboxes weren't always well designed either so those things in combination may have made the K&N filter a better choice than stock.

Much like points ignition though, those days are pretty much gone.

 
Back in the old days of carbs before fuel injection became the norm, K&N may have offered some advantage over stock. Of course back then airboxes weren't always well designed either so those things in combination may have made the K&N filter a better choice than stock.
Much like points ignition though, those days are pretty much gone.
Back in the days of carburetors a "low restriction" air filter leaned the mixture for more HP and MPG. Nothing one couldn't do tuning the carburetor properly. Today the air filter does not fool the fuel injection ECU.

 
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