Purchased a 99 gs1200 for a song.Bike is COLD natured, coughs, sputters,andknocks when cold.Cleans up well after warm up,but will run rough at random.Rebuilt carbs, installed Ivans jet kit,air box mod, 5degree spark advance/Yoshi pipe.Runs like a bat out of hell,when right,but will not run consistently.Someone help me before I put this bike out of it´s misery!