Stale fuel is the number one cause of small motors running poorly, we’ve got the tools to help you mix the right amount to keep your fuel fresh and your engine running right.
Calculates the correct 2 stroke ratio mix and saves the date you mixed it.
First and foremost you need to know what type of engine you have (and whether it requires premixed 2 stroke fuel) and what fuel to oil ratio to mix.
Pretty much all petrol engines fall into one of 3 types:
Uses straight unleaded petrol and stores engine oil inside the motor. (cars and larger boats and garden machines)
Has two tanks, one with straight unleaded petrol and the other with 2 stroke oil. It automatically mixes the fuel and oil as it enters the motor. (outboard boats, jet skis, snow mobiles and some modern motor bikes).
Most likely why you are here and require you to add the oil to the petrol before you put it in the tank. (Older motorbikes, small outboard boats, chainsaws and smaller garden equipment like leaf blowers, mowers and whipper snippers/trimmers).
Different premix 2 stroke engines/motors take different amounts of oil per litre (gallon) of fuel as well as different grades of oil. For optimal performance, make sure you read the manual and use the right ratio and oil specification.
If you don’t have a manual, search online for your make and model number.
Also don’t cheap out on what oil you buy, a few extra dollars spent on oil can save you a large rebuild bill later on. It’s always best to use the manufacturers recommended oil specification.
Be sure to use the correct 2 stroke ratio as too much or too little will damage the motor!
If you’re old-school and like print things we have a series of printable 2 stroke mix charts for download in all the common 2 stroke ratios in both metric litres:millilitres as well as US gallons and fluid ounces.
To make your life a little easier we have a free 2 stroke mix calculator on this page for you to use any time.
If you have an Apple phone or watch, we have a free app on the App Store that lets you save profiles for multiple containers storing the 2 stroke fuel ratio and last time you mixed a batch to ensure your fuel hasn’t expired.
For all of the above methods you start with the desired 2 stroke fuel:oil ratio, then enter the amount of straight petrol you want to mix. The calculator will tell you how much oil to add on top of the fuel amount (no need to subtract the oil amount from the fuel).
It’s best to mix small batches more often to ensure the fuel doesn’t go stale.
Grab a fuel safe container (different countries have different regulations on this) and fill it with the amount of straight petrol entered into the calculator. It’s generally easiest to start with an empty container and fill it from a petrol bowser.
Add the calculated amount of oil on top of the straight unleaded petrol and give it a good shake to mix it, your fuel is now ready to use.
Don’t use more than 10% ethanol as it may damage your 2 stroke engine.
If you’re just mixing a random batch of 2 stroke fuel (2 cycle gas), please use this simple free fuel mix calculator:
We have a comprehensive article that goes into detail here, but in general it largely depends on the ambient temperature the fuel is stored at.
All fuel will expire quite quickly (no just 2 stroke), from 1 to 6 months depending on what temperature it is stored at.