Unfortunately, no. Those were really their claims in ads and magazine articles. Bear in mind that I'm talking about sometime in the 70's when they were still a new innovation. A whole lot may have changed since then, but after that first impression I've literally never looked at gauze filters again. I'm not a performance or ultra-mileage rider, so buying a new paper filter every few years just isn't an issue for me.
No worries GravyDavy. I was reacting to your question
“Does anybody know if they are publishing the micron rating of a new, properly oiled one?” when I had just, minutes before, posted links to specific, independent information.
I truly get it that none of this might matter, at all, to some folks. But I guess I could have also mentioned that the FAA has certified K&N filtration for aircraft. One supplier cites:
“K&N re-cleanable air filter media
Up to 50% more air flow with the same dirt holding capability
NO ADS (Airworthiness Directive)
Increased horsepower
Reported fuel savings of .3 to .5 gallons per hour”A third to a half gallon saved per hour is a big deal for pilots. Not so much as a money saver but for the effect on available range. (from 6000ft you can’t just push your plane to the next gas station) Even if one only looks at it from an ecological viewpoint including the notion of the disposables… it is not just a drag strip thing. Don’t know if that matters.
Last, how often one changes a air filter is subject to a lot of considerations. One consideration should be that as any air filter gets covered with dust, it creates a vacuum on the fuel intake side. Paper filters are more prone to eventually suck the particles right on through much sooner.