Oil ratio for chainsaw
If you need a 40:1 gas and oil mixture, use three ounces of oil for one gallon of gas, 6.5 ounces of oil for two gallons of gas, and 9.5 ounces of oil for three gallons of gas. You can also buy premixed fuel for 2-cycle engines. For example, a 40:1 ratio is 128 ounces divided by 40, which is 3.2, rounded to 3 ounces, needed of 2-cycle oil for 1 gallon of gas. Things You Will Need Owner's manual As you may have noticed, most brands these days prefer a gas-to-oil ratio of either 40:1 or 50:1 for their chainsaws. As long as you use a high-quality 2-stroke synthetic oil , it doesn't really matter if the ratio is 40:1 or 50:1.