Thanks for the info. I was only wondering just if...
I use Quick Silver 2-stroke Oil. Never had a prob with any of my engines using it.
However, every two years or so need to clean all the carbs of that green (bluish/green) deposit that sits on the carb mebrane after the engine stands for a while. Have to strip all the carbs out imerce them in the carb cleaner staff for 24 hrous and back on again.
I also use Super unleaded (Shell VPower or Shell optimax or something as it is called in the UK) just in case it burns cleaner.
Have not noticed any differenceso far but will keep doing it for a while and see.