Back in the day every kid in America knew how to a B&S engine run, most of them smoked like crazy. I would not expect any used B&S engine I found not to need work. I am more interested to find out when the Mickey Bike was made, that way the right year fan shroud could be put on a B&S engine, I have some shrouds from the 60s. Eihter way the Predator or the B&S I have is not original to the frame. The tires are also Chinese, I did not know that when I ordered them. I have the original Goodyear tires that came on it.