i have a 07 kingquad 700. the problem im having is,  when i start it up it idles fine for a minute then dies or if i put it in gear it dies.  there is oil coming out of a small hose in the rear of it behind the brake light, almost like a vent tube...
if i get it to go in gear it runs great its not sluggish, it just wont idle or if i slow down real almost to a stop it dies... im clueless can anyone give me help thanks!!!!!  

unless it was overfilled with oil or rolled on it's top it shouldn't be leaking oil from the tube.

it does sound like either a fuel/air mixture off or a valve issue.  

thanks for the reply, i was thinkin the same thing with the fuel and air, but i checked the oil it was fine and, its never been rolled or on its top...
it was very dusty and i checked the air filter and it seemed to be in good shape. but i'm with you on the valve issue.