what jet kit for a big gun and k&n??????

[400exbiggun]

hey guys, i got a 400ex, and the previous owner put a jet kit on it. the only complaint is that the ex floods its self over night almost every night(or close to that). yes the choke and gas are turned off, but it still floods. Does it have too big of jets? i don't know make or size, but do any of you run this setup??? what do you have? what is a good jet kit, so i don't loose power, or possibly get it more power(yeah!!!:D )??
it has a k&n and big gun race slipon, but plan to get header soon.
P>S someone told me that dropping the needle one position might help, will it??

[VIGILANTE MAN]

I've got a 400ex with a full Big Gun Race system and a K&N filter and believe it or not, the stock jetting worked out the best (I think it's a 148 - someone correct me if I'm wrong). Granted, I'm running the stock airbox lid with no modifications. I did raise the needle one notch.

Nevertheless, your jet size should have nothing to do with the flooding. I've had my float shut off valve (or whatever it's called) in the carb not close due to dirt in it - this caused a continual gas leak.

But, if your fuel tank petcock is closed, that shouldn't happen. Could the petcock be bad?

[400exbiggun]

well, i close the petcock, and it does run out of gas, but i open it and it runs good. i start it cold with no choke, because it runs soooooooooo BAD. i don't know why. that's why i was thinking jetting.

[cals400ex]

since you said you have a jet kit, i assume that you have the dynojet kit. this will come with a new needle and new main jets. i am not sure but it my come with new pilot jets also. i don't think dropping the needle will help much. the needle adjustment is for 1/4 to 3/4 throttle. if the bike runs rich in this throttle range, then i would move the needle. i moved the needle up one notch on my bike and what that did was make the bike not miss or hesitate when it is cold out side. however, the bike is jetted lean from factory so moving the needle up one notch helped get the bike to the proper air/fuel ratio. the pilot jet is for idle to 1/4 throttle, so this jet is the one for starting the bike. i bet that the pilot jet is just too big. i know the sizes of dynojets are different from sizes of the factory keihin jets. what color is your plug? if you let the bike idle for a while, does it look black and full of carbon?

[stiffy]

YOu can E-Mail Big Gun and tell them what's on the bike and what elevation you are at and they will tell you what jet sizes it needs I have a 158 Main and 40 Pilot in mine but I'm at 2200 feet

[400exbiggun]

the plug is black. i start it, and it runs a little bad, so i rev it a little, and a small amount of black smoke comes out. (not like a 2-stroke, only visible if ya look for it)

[Buffalo400]

Hi
Your bike run so bad when is cold, all 400ex run low rpm at cold and shut down time in times... When your bike is hot, does it run correcly at idle????? that the question!!!! if no, you must change your pilot jet... My bike run corrcly at idle when is hot but when is cold......It,s hard... but I will put a 42 pilot jet soon... for the smook, it can be your black oil but also it run just so bad....
:confused2

[400exbiggun]

yeah, it runs good idle, how do i adjust that thought? where is the screw? cause can be at a complete stop let go of the clutch and it will move without me giving any gas.:confused:

[jhr400EX]

I would do like stiffy said and email or call big gun and see if they can help with the jetting. And I also run a 158 main and a 40 pilot with the stock filter and no airbox mods and it is dead on for me.