I just purchased a prefilter for my 2003 400 indy Cat. My question is how well do they work? The instructions say not to oil the foam or the prefilter. Is the prefilter that good that you dont need to oil? Thanks

 

Joks, this is a good question, I have wanted to run a pre0filter myslef. I hear they eat a few horsies. But often times people modify based on gaining power and looks etc. But I think I will sacrifice a few horsies to improve reliability and treat my motor a little better. I ride alot of dust and wet stuff. I would like to read some posts from gusy that do run these pre-filters and see the actual losses they suffer in performance versus the gaisn of better air cleaning. I thank you for your replies in advance guys.

 

As i understand it they are more for element filter like KN, i wouldnt use one on my Uni. Thats the point of a foam, the oil grabs the small stuff, same thing as a pre on an element filter. On the inside of my uni, its like new. So to me that means no small particles are building up.

 

I have one on my 2003 500i and do not notice any differance in power or speed the one I have slip over the main filter and is like nylon type meterial.

Bob 2003 500i