I have an 04 Honda 400 ex. The thing runs fine when I keep some throttle to it and while out riding. When I try to let it just idle it dies. At idle the carb essentially "coughs" air back out of it and it stalls? Ideas? I don't know where to find the idle and jet adjust screws. The way the carb is packed in there I can't see much. Any help greatly appreciated.  

try reading thru this, it may help

sounds like the needle is out of adjustment, may need to be adjusted up.

http://www.3wheelerworldforums.com/showthread.php?t=55086