I am thinking of putting K&N oem filter replacements on my Raptor and 250EX.Anyone out there installed one and how did it work?Any mods needed?

As for the Raptor, don't use the OEM Replacement Filter... we have seen that this does not seal correctly.

The best K&N set-up we have seen is the GYT-R product. Follow the instructions and make sure to trim the airbox support on the inside of the air box (facing front from the back of the box, it is on the left side) a bit to insure the new filter clamps on properly.

Pay attention to proper filter oiling procedure, not too much, not enough etc. Use a pre-filter (GYT-R Outerwear) without fail.

I put on the pro flow kit that Alba sells, it comes with the pipe, no problems as of yet, basically its a aluminum adapter and k&N filter, throw an outerwear on it and good to go. might want to check into jetting, you may need to fatten it up a bit since you have alot more air flow. I jetted mine with the pipe so I dont have any specs for ya. but its worth it, easy to clean, overall saves money, and time.

yeah the oem replacements are no good, go with the setup ian has