Depending on the age of the Tornado fuel, because "older" Tornado fuels (5 Liter cans) don't have castor oil in it, it is a full synthetic based fuel which burns completely clean. After run oil very much recommended.
There where 5 Liter cans of the so called "Sydney formula" which had a percentage of castor oil in it, and the latest Tornado fuels which came in the 4 Liter/1.06 Gallon cans are based on this "Sydney formula"...
But still I ALWAYS with ALL fuels recommend people to use after run, after every meeting and even if you are going to use your engine the next day again.
Have you check the price of a bottle of after run?
that's why I use almost 2 a year.....