Husqvarna's chainsaw gas and oil mix is designed for hand-held equipment with two-stroke engines that require less power than other internal combustion engines, according to Husqvarna's website. Examples of lower-power engines include those for chain saws, leaf blowers, trimmers, jet skis, mopeds, smaller outboard motors, dirt bikes and radio-controlled model airplanes. Husqvarna's gas-to-oil ratio is 50-to-1 for its mixture.
Smaller engines that idle for long periods use a mix of oil and gas in order to prevent degradation and oxidation over time. Such mixtures can last for years in a small engine without ruining the equipment. Gas and oil comes pre-mixed, or consumers can mix their own.
Ratios of gas to oil vary from 16-to-1 up to 50-to-1. The larger number in the ratio represents gasoline. A 16-1 ratio means 16 parts gasoline to one part oil. For a 50-1 mixture, one gallon of gasoline needs 2.5 ounces of oil. Five gallons of gasoline require 13 ounces of oil for a 50-1 mix. Different equipment may need different ratios of gas to oil.
Oil and gas should be mixed in a gas can and not in the gas tank of the equipment. Put oil in the gas can first, then add the correct amount of gasoline. Do not use gasoline more than 30 days old to mix gas with oil.