400ex jetting

[glowinzr2]

ok i have a 400ex and i need to do some jetting. i have jsut go in my big gun full exhaust. i also have a k and n with outerwears and the airbox lid removed. and if it matters i also have a 14t front sprocket. ok i think thats it. any help with what i should jet it with and how would be great.



aj

[glowinzr2]

there has to be one person out there that knows how to jet a 400ex.

[SGA]

There is, but this question has been asked 2007 times. Use the search feature, type in jetting, and you will find dozens, no hundreds of threads on jetting a 400ex.
My guess would be a 160 kehin main, 40 pilot. Big gun should have recomendations on their website also. hope this helps.

Haha, i just went to search, typed in jetting, and got 1,695 matches!

[MIKE400EX]

I had that setup w/a modified quiet core also. Worked best w/a 165 main, 42 pilot and needle clip moved down one groove (4th down). Should be real close if you have the race core. That was at sea level and worked good up to 1500 ft. Hope that helps!

[SGA]

MIKE400EX is right. I ran the K&N, open box, choked removed, with a yoshi exhaust. I forgot to mention moving the clip down one notch. I had to do that to mine or it would bog when you nailed it. A 165 was a bit to fat in mine, the 160 brought the plug to a nice tan color and made it jump! I used a 40 pilot, it started and ran good. never tried a 42