I'm working on a 400 big bear and I can't seem to get it to idle right. I've cleaned the carb several times. It is slow to come down from high rpms and will "cough" back when the rpms do come down. The choke isn't stuck, all passages have been thoroughly cleaned and the diaphragm is working correctly. Also, no cracks in the boot. What size main and mid jets go where? I may have swapped them on accident, the bigger jet is in the main jet spot right now. Could the calves cause this problem?