01 400ex popping..

[Ddw350]

at like 1/8 to 1/4 throttle, popping and burps terrible..it will stall out also.its my nephews and it has dg slip on and a uni filter with no air box cover,i tried covering the box and it hardly ran! after 1/4 throyttle it runs fine.dont know the size of the jets that are in it either,someone may have fooled with it.

[ditchmud]

I would suggest that you check the sparkplug. What color is it? The color of the plug will tell you a lot. If the carb has been cleaned and you still think it's a jetting problem then look on the trikesylvania page of this forum. There is a thread called "carb jetting 101" (or something like that) It is a very helpful instructional thread on helping you understand and achieving proper jetting.

[Tri-Z Pilot]

Richen up your idle mixture, I bet your cracking and poping when you let off the throttle arent you? If the mixture screw is behind the carb tower ( where the slide is housed) you turn it clockwise to richen. If the screw is in front of the tower, turn counter clockwise to richen. Richen up the mix till it stops. If you are making too many turns in or out with no success, go up a size or two on the pilot jet. For example, you dont want the screw turned out too far or it will vibrate out.

[clarkfabracing]

also check to see if it has a dynojet needle in it,if it does make sure the clip on te needle is 3 up from the bottom,if its not put it there and try again!