My 2005 Rally 200 ran fine the last time I used it, now months later it idles fine but any more trottle and it wants to die, sputters, and runs rough. Now my question, is there a way to tell if its gas gone bad inside the carb and varnished the inside or if the carb needs adjustment of some sort.

 

Sounds like it just needs the carburetor cleaned... assuming that theres a good supply of clean fuel to the carburetor. Also, check the airbox to make sure no critters have built their house there...