Recently acquired an 83 GS850L after a death in the family. I know this will sound silly, but does it need gas or oil-gas for fuel? I have read in some reviews it is a 2 stoke, and 4 stroke in others. Which is it? Many years ago I had a benelli 2 stroke needed gas-oil. Friend had a Honda 4 stroke, needed gas only. Another friend had a 2 stroke that you put gas in the tank, and oil in another tank which mixed with the fuel...