question bout flat cr carb....fcr-mx?

[bigballz400]

i bought a 400ex.....rev box....pipe k&n...thinkin its 440....anyways it has a flat cr carb on it and it dont want to idle.....idles down then idles up then down again....run like a mother f***er wide open......is this how these carbs r? and another question......wats w/ the electic plug thats off of it?? is it hot start?.......im clue less to this carb

[drew416ex]

try going up one size on the pilot. Mine has a steady idle, but it did you what you described until i rejetted. As far as the plug im not sure. I think some of the newer ones have a throttle positioning sensor or it may be the hot start like you said.

[bigballz400]

alright thanks....ill try