Joe,

I haven't adjusted a YS bleeder as of yet. However the bleeder carb carbs on 2 cycle glow engines work a bit different than those with a low speed needle to adjust. As you open the bleeder screw you are in effect leaning the mixture or adding more air to the idle mixture setting. Thats because you are controlling the air mixture not the fuel. So if you close down the needle it gets richer less air introduced into the mixture. I also use the pinch test to get the mixture set correctly. If anything I prefer the verge of being a bit too rich which the engine transitions well out of over being a bit too lean.