Ok, I have a stock 02 Warrior. I just opened up my air filter box and I saw a Red UNI air filter... I took it out and yep.. it was UNI. It has no prefilter/wrap, but it was a red UNI air filter with the metallic small grid-like cylinder being covered by it where the air comes in. Is this stock, or did the person before me put the UNI on it? Thx.

Should I keep it or go with the K & N pro flow set up?

 

a foam filter doesn't need a prefilter... and UNI's aren't stock :-p if u get a K&N you need a prefilter unless u are riding dunes only..

 

When should I clean it? What should I use on it.. water?

 

i switched to the k&n, but when i had my foam filter, I made sure i cleaned it everytime. you can clean it in gasoline, water, or soap water. or thats what i used at least