I adjusted the gap after about 1 gall., I'll check it again.


I don't mean to second guess you, and I will go fly it, it just seems to ME that that rat-a-tat sound, kinda like an A.K. 47 (above the cool 4-stroke sound) seems abnormal, I don't hear this with other 4's at the field (comparing to saito, I haven't heard another YS run). But if your telling me this is a normal sound for a ys engine to make, and isn't harming it, I'll try getting used to it and keep flying. My long story above was motivated by wondering (an idea I formulated, after hearing the spark knock scenario) if a slight bend in the conn. rod (or lifters) could have messed with timming, causing pre-igniton.


Like I said, I'll quit worrying about it, unles you tell me otherwise......again.