so i figured the previous owner of my 1993 kx500 had a fuel/mix rate about 20:!? becuse it's smoking alot and oil as been dripping from the exhaust scilencer, so i got to the nearest gas station to get 10 liters of gas to mix at 40:1 rate, but since i never owned a 2stroke bike before i don't have any oil to mix in the gas, and i'm wondering if the bottle of shell advance vsx is any good?