The jet kit has a different needle which changes the fuel curve it also comes with instructions and tells you what jet to use with what setup and at what altitude had one on my stock carb it is worth it.

99 426ex , Web Cam, FCR carb, CT revlimiter, DMC exhaust, XCT's ,K&N, One kit,

http://www.trxoutlawz.com/

 

Do the instructions in the K&N Kit have a set up for the stock pipe? What does it say about the air box lib with the stock pipe? Thanks

 

Hey guys good information, just a quick question after having my 400ex for only a week and ridden for a few hours I took the seat off and adjusted the throttle cable and I was really suprised the amount of dust and grime on the air box lid and surrounding areas. It makes me very nervous to remove the lid or put holes in it for that matter am I just overprotective ?

 

Yes to all their setup sheet is very good.