Well, no, actually. Every season, every single petrol powered garden tool I own - three chainsaws, 2 strimmers, a hedge trimmer, a rotovator, a leaf blower and various mowers will either not start at all or run terribly if left on the old petrol from the previous summer. I am also currently rebuilding the engine of a motoculteur belonging to a friend who ran it flat out on old petrol despite it missfiring and ruined the engine internals. Drain the old stuff and put in fresh petrol and they all run perfectly. I agree, the modern unleaded fuels seem to go off very quickly, my Honda 4 stroke mower which normaly starts first pull, will not run with fuel that has been left longer than a couple of months. Les