K&N Filter and rejetting..

[Breyon55]

OK this past weekend my g/f and i both got our 2002 300 and 400ex's. We plan on mostly dune riding. How hard is it to re jet a 400? If we put the k&n on her quad, do we have to re jet hers also..thanks
Brian

[VegasEx'r]

It's pretty easy to change the jets on a 400. The first (couple of?) time(s) you may want to pull the carb off, but after you know where everything is, you can do it with the carb still on. Remember to turn off the fuel petcock. There is a plug w/ a hex head on the underside of the carb, remove that plug, let the gas drain out. If you look inside there, you'll see the main jet. It is a small, hex-shaped brass thing that you can remove with a small socket. Have fun w/ your new toy.