Little 400ex Problem.

[KawaBoy]

I have an 01' 400ex with a White Brothers E-series slip on and K&N filter. (Motor is stock) It seems to me that i am running too lean. I just purchased a DynoJet jet kit and the instructions told me to run a 146 main with clip on 3rd notch on needle. It still seems a little lean. Can anyone tell me what size main they are running with my same modifications? I'm under 3,000 feet above sea level. Any help would be greatly appriciated.

Thanks,
Justin

[KawaBoy]

Anyone???:(

[JOEX]

That is probably about right. Dynojets have a different numbering system than the stock Keihin jets.

[nosliw]

similar mods and i run a 155 keihin

[2muchquad]

how do you know it seems a little lean?if you are running more than 8disc in your slip on,you could need richer jetting.the more you have the more you will have to richen your jetting;)

[RiderTRX400ex]

i got same mods with other stuff in my motor, i run a Dynojet 155 main, but with stock pilot. im still looking to get a 42 pilot jet which ive heard will help.. check your needle jet holder, which is the brass piece that has a nut on it, that your main jets come off from, below the nut there should be 2-3 threads showing.. mine got messed up when i changed my jets, but i did what i just mentioned and it runs great now... still need that pilot and maybe go up to a 160 MJ..


Good luck

[KawaBoy]

Originally posted by 2muchquad
how do you know it seems a little lean?if you are running more than 8disc in your slip on,you could need richer jetting.the more you have the more you will have to richen your jetting;)

I pulled the plug and done a plug check after getting it back together and riding wide open. I took the plug out while the motor was still hot and it looked white like it was running lean but the bottom side of the electrode had a gold tint but the rest of the plug was white. Thanks for everyones help!

[KawaBoy]

Anyone else?

[cals400ex]

i would run the 146-155.