the mixture you need is 40 parts petrol to one part oil.So 1 litre of mixed fuel would be made up of:
0.975l unleaded petrol and 25ml of two stroke oil.
Oldhenry, January 2010
40 parts petrol to 1 part 2 stroke oil (40:1)
So thats e.g 4.875 litres petrol + 125ml of oil