I’ve never used any kind of fuel stabiliser over the winter and have never had a problem starting in the spring. I park it, disconnect both terminals of the battery and cover it up. On startup in the spring, I do have to smack the carb with a rubber hammer as the needle valve can get stuck shut but once I do that, it’s good until the next lay-up time. I’ve never worried about the fuel level-maybe there is moisture in the tank but the first thing I do in the spring is fill it up and drive it for a couple of hours and all is well.