The following chart tells you how many ounces of oil to add to a gallon of gasoline to properly mix fuel for your 2 stroke engines. Older engines typically use 30 to 1 mixture ratio’s and new engines tend to use 50 to 1 mixture ratio’s. Always check your engine’s documentation for the proper mixture ratio. Buying a quart of 2 stroke oil and something to measure the oil in, is a lot cheaper than the little bottles of oil they sell and much cheaper than the pre-mixed gas they sell.
Because I currently use 2 stroke mix for just my weed wacker, I took an old quart gear lube bottle and used it to mix the gas in. The gear lube bottle has a nice spout on it with a cap and since I don’t use much 2 stroke mix a quart works out great. You don’t want to leave 2 stroke mix laying around and end up putting old 2 stroke mix in you engine, it can damage it. Another tip is that it is always better to have a little too much oil, than not enough. Not enough oil in 2 stroke mix will also damage your engine.
Ounces of Oil to 1 Gallon Gasoline
- 16 to 1 8 oz
- 20 to 1 6.4oz
- 30 to 1 4.3oz
- 32 to 1 4 oz
- 40 to 1 3.2oz
- 45 to 1 2.8oz
- 50 to 1 2.6oz
- 60 to 1 2.1oz
- 80 to 1 1.6oz
- 100 to 1 1.3oz
What type of 2 stroke oil should I use?
It’s not always the case, but most of the time almost any 2 stroke oil will work. Exceptions to this would be race engines and perhaps some of the newer fuel injected 2 stroke engines found on dirt bikes, boat engines and other modern vehicles. Specialized 2stroke oil didn’t really come around until the late 1970’s. “Back in the day” you would use regular motor oil, or possibly castor oil. Those oils require much more engine maintenance and spark plug changes. Modern 2 stroke oils have additives in it to lubricate better, foul plugs less, not be as smokey, and also special oil for fuel injected systems.
2 stroke oil terms
2 stroke oil is the same thing as 2 cycle oil. The mixed gas can be called 2 stroke mix, 2 cycle mix, and premix. This all means that you have mixed the gas and oil together in a jug or container. There is also the term Auto-Lube. Auto-Lube means that there is a separate oil tank that you put the 2 stroke oil in, straight, not mixed, and a special pump on the engine mixes the gas and oil together for you. Auto-Lube system makes filling the gas tank easier because you can just put gas in the tank and not have to fuss with mixing the oil in.
2 Stroke Porting vs RPM
General port timing to peak rpm
Generally speaking this is the amount of degrees the intake ports are open and the Revolutions Per Minuet that the engine should be able to spin. Obviously there are other factors involved, that is why this is just a estimate of what to expect.
RPM vs degrees port is open
- 6000 120 degrees
- 7000 122 degrees
- 8000 124 degrees
- 9000 126 degrees
- 10,000 128 degrees
