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rsimmons_82
03-09-2005, 04:00 PM
ive got a brand new 400ex (2004). Since i bought this brand new, im a little stapped for money and cant really afford a pipe at the time. i cant stand it being so quiet, so i decided to cut out the silencer and i reinstalled the spark arrester to make the park ragers happy. I also removed the airbox cover to bring in more air to the stock filter. my question is "do i need to rejet the stock carberator, how do i know if it needs rejetted, and will i damage anything by not rejetting it?

like i said, its all stock with the exeption of the removal of the silencer and airbox lid being removed. oh yeah, im about 1800 ft above sea level.

if anybody know what size i know or how i find out what size jets to get let me know.

rsimmons

cals400ex
03-09-2005, 04:10 PM
i would start with a keihin 152 mainjet. you may want to put in a 42 pilot jet or at least turn the fuel screw out a little bit.