The drop of oil on the underside of the magneto cover was from the oil coming out at the spark plug. After I deal with my broken chainguard and right side shift kit chain that has become loose I will start the engine for the express purpose of trying to find a leak. I had previously checked the intake and found no leaks there. Next time I'll focus on the head gasket and base gasket. Are there other places I can try? Someone suggested I use my map gas torch. Is this a bad idea for some reason? I'd rather not use WD-40 as it leaves a residue. I also have electronics cleaner which leaves no residue and has about (to my eyes) three times the fire power that WD-40 does when tested with a lighter.