K&N Red Air Filter Oil Coloration Disappearing

[Ellar]

I bought and installed a Joker Machine HP air cleaner with a K&N 4" round filter to help solve knee/shin clearance issues. I was on a ride a month or two later and happened to look down and notice my filter element was totally gray. I washed and oiled the filter that weekend and a pretty impressive amount of brown water came out. I figured the filter had caught so much stuff that it had been coated with gray dust.

Four days later I looked down and noticed all of the red indicator is gone again. Is this normal? Is the oil still in the gauze beneath the surface? Not really digging the idea of re-oiling this thing every four days.

[Toejam503]

Once a K&N starts trapping dirt, they don't stay red. On cars, you're supposed to be able to go 50K miles before cleaning and re-oiling. On my bike, I clean it once a year, it's usually black/gray. K&N claims that the dirtier it is, the better it works and suggest cleaning it every 30K-50K miles.

[Ellar]

Thank you!

[Wiktor]

I called K&N a couple years ago about that and they also told me that the red dye is not UV resistant and loses its color. Shouldn’t have happened that fast though! I think the smaller filters also lose their color due to picking up dust faster because they’re sucking a lot of air through a smaller area.

[Tomcatt]

The red coloring helps you oil the filter evenly. Nothing more.

[Steve9]

Red matters...

[rejeanprimeau]

I have red dyes for liquid penetrant inspection, 20$ a can Call Ardrox for 906 and tell them I send you. LOL