carb adjustment

[powersmoke03]

I just rebuilt my carb on a 2002 400EX. I counted my turns when I took it apart but now my header pipe gets red hot after about 5 minutes of idling. that means that its running lean, right? there ussed to be a link to a site that had the service manuals for 4-wheelers, anybody know what it is? Or can yall tell me what might be out of whack. Any help would be appreciated

Sean

[AtvMxRider]

http://www.exriders.com/vbb/showthread.php?s=&threadid=78446

[powersmoke03]

So how to you adjust the mixture? Is it the screw located underneath the bowl next to the pilot screw? Anybody know what it should be set at?

Sean

[JOEX]

The mixture screw is located right behind the idle adjustment screw, you can see it easier from the right side of the motor.

Stock setting is 2 1/4 - 2 1/2 turns out from just seated.

Joe

[cals400ex]

your probally running lean on one or more of your jets. try and see when your headers are glowing. are they glowing at idle, at mid throttle positions or when the bike is floored? this will help us figure out your problem hopefully. also mention your mods and what temps and altitude if you know it.

[powersmoke03]

Because I had fuel leaking from the carb. I purchased an o ring kit and new plunger that connects to the float. Replaced all those things and started up. Because it was dark out I noticed the header pipe starting to glow red after about 5-10 minutes of warm up and just one additional minute.. I turned the screw 2.25 times after the carb rebuild and its running fine and no longer leaking but noticed the glowing. I think if it was daylight I may not have notice it..

It was 50 degrees and it live at 0 elevation.

[cals400ex]

if you are just doing some normal riding and the headers start glowing (from 1/8 to 3/4 throttle), your needle is probally just lean. what mods do you have done?? you running an airbox lid? if you have any mods and it is getting colder outside, i would just move the clip down to the 4th position. this should stop your headers glowing. take your bike out and get them glowing. then come to a stop and see if they glow in a few seconds at idle. if not, your fuel skrew is plenty rich, but your needle is probally lean. you can also see if they glow at full throttle. if so, your probally a little lean there too.

[powersmoke03]

no mods, stock all the way. took it outside tonight. started it up and within 1-2 minutes of idling the header pipes were red hot. Does this make any difference in the fix?

Sean

[cals400ex]

yes it does. you have a fuel skrew on the bottom of the carb. its a bronze color. start turning this out in 1/4 turn increments until it stops glowing. you may have to do this over a hours or so, because you won't be able to get to the fuel skrew with the engine and header hot too well without taking the carb off. i would probally just start at like 2.5 to 2.75 turns out from LIGHTLY seated. however, if you go out to 3.5 turns, i would just get a new pilot jet. you are not suppose to go out much farther than that. if you need to go out farther than that, i would just get a 42 pilot jet. let me know how it works.