by cleaning it every 3k miles u are letting in a lot of dirt. Look at the SAE J726C test and u will see how much a K&N lets in until at the end of the test, where it is then 97% efficient, the # they like to boost about. paper air filters are 95-97% efficient at the beginning of the test and near 99% at the end. K&N is a race track item and shouldn't be used on the street.
K&N plays with the facts and testing to sell products. Their org test way back in the begiining to prove their filter increased HP was to use a car that had an OEM undersized air cleaner which restricted the amount of air going into the engine, add their filter or no filter at all and HP goes up. And remember the HP was at the upper RPM ranges where most riders and drivers of vehicle rarely drive at if at all.
The OEM filter will last longer than 12k miles and flows more than enough. remove the EPA noise screen mesh from the bottom of the filter for even more airflow.
http://www.roadkill.com/~davet/moto/air.filters.html Sae test
http://www.knfilters.com/images/factstab1.gif K&Ns own test, grams of dirt are being let in until the end of the test, translates thousands of miles dirt getting into the valve stems and rings before the filter is at 99% efficiency
http://www.google.com/search?hl=en&source=hp&q=Arlen+Spicer+airfilter+test&aq=f&aqi=m1&aql=&oq=
