How much oil to gas mixture is there on a 1978 115hp evinrude?

For a 1978 115hp Evinrude outboard motor, the recommended oil-to-gas mixture is typically 50:1, which means 2.6 ounces of oil per gallon of fuel. It's important to use a high-quality two-stroke oil designed for outboard motors. Always consult the owner's manual for specific guidelines and adjustments based on operating conditions.