400EX idle stalls

[LostCause439]

I just purchased a 400EX everything runs good but she wont stay idle for long, when shes in idle she can run for a little than stall out. New to the 400EX and its carb. Could this be a fuel mixture adjustment? The idle doesnt need to be raised as she has a good rpm when she does idle

[a4guy]

Before i re jetted my 400 did this.

Are there any bolt ons on the quad? What jets are in it? Does it back fire on deceleration?