05 trx 400ex PROBLEM

[sixer3]

I've got an 05 400ex got in december of 04 had maybe 4 weekends on it, and now it will NOT idle at all, and seems like its choking off at low rpms, once i hit the higher rpms it runs like new, but at lower rpms theres a slight backfire type of sputtering, and will not idle, choke isnt stuck, air filter's clean, valves are adjusted, i ride in the dunes, jetting should still be fine, air/fuel mixture seems to be wrong but i cant seem to find the jet for that any help? anyone even understand what im saying?...heh

[nosliw]

any mods done to the bike?

if not try cleaning the carb really good. take out the jets and shove your carb cleaner straw down there and take your time. could be a small piece of crap that got in your fuel jug when you were filling up that is partially blocking a jet. make sure your fuel screw is a good 2.5-3 turns out also.

[sixer3]

no mods to the bike at all, cleaned it out reallly nice, fuel screw?......i have on 05 so it has the kinien carb and i think im missing the air/fuel mixture jet but since theres 2 screws there as opposed to the pre-05 ones with only one screw so im not sure what im missing and dont have the owners manual to look at a diagram of this particular carb....

[NacsMXer]

Change out the spark plug if you haven't already and see if it makes a difference. I know I had similar problems when my 400 was still stock and the plug turned out to be fouled. A new plug seemed to help quite a bit for me.

[TunedPerforman]

the air/ fuel mixture screw is on the bottom of the carb on the carb body just behind the intake mounting boot.