No-one else sticking their head above the parapet?!
Oh well - at the risk of creating a long-running thread already repeated across most other forums I’ve looked at before......
I’ve seen that article before. Interestingly, K&N cite exactly the same ISO standard (5011?) as the one their filters
are tested too, suggesting “...K&N air filters generally achieve overall filtration efficiency in the range of 96% - 99%. The fact that our air filters at times reach overall filtration efficiencies as high as 99% while maintaining high airflow is a testament to the quality and capabilities of our oil impregnated cotton air filter medium”.
https://www.knfilters.com/mobile/filter_facts.aspx
If we’re taking one ISO-standardised test as gospel, we have to take the other one too!
The above link also has further links for graphs to ‘independent’ K&N test results.
I’m not saying who’s right and who’s wrong, but who are you to believe? I’d like to see a similar test of the OEM filter.
The guy who wrote the pre-amble to the tests on
@eddie ‘s link also sounds like he has a bit of a K&N-shaped grudge, to me (he even calls it a ‘crusade’). It’s just inaccurate to state aftermarket air cleaners can’t increase HP as well. My seat-of-the-pants dyno felt it after fitting my K&N. Not very accurate, I know, but Ivan also states air filters make the greater difference on our bikes than a pipe change. Indeed, K&N’s own dyno chart for the filter for our bike, shows a 7hp increase:
https://www.knfilters.com/dynocharts/RK-3940_dyno.pdf
Are they lying? That report author might say so. Have they fudged the dyno results? Atmospherics causing false readings? Maybe 1 or 2 hp, but not 7.
Sorry for the long post, but I’m on nights’ tonight, and bored.
I await the multiple scuds that will no doubt now come my way!
Ben