Hi all. I find that my Thor 100 engine with Walbro carb is running too rich and always has, it still has only about 9 hours on it and I have heard that somehow they run better after 10 hours or so. I have already peppered the underside of my wing with oil spots on one occasion and am keen to prevent it from occuring again. The manual states that the standard calibration of the mixture screw is one and a quarter turns out. For anyone on the forum that has this engine, have they had to adjust the mixture for the same reason and if so how did they find the best position. Also due to the position of the screws I cannot get access to them with the engine running.