Keep working with the guy that knows about engines. Get him to help you figure it out. Small pieces of debris can cause havoc with the clearances on the spray bar assembly.

Don't pull the low speed needle to clean the carb. It just messes up the settings. Its better to just remove the entire barrel. There should be a stop screw on the crankcase that prevents the barrel from coming out. Just loosen that screw and the barrel should come right out. Make sure you don't loose the spring. This will allow full access to the fuel passages. Flush them all out with clean fuel. Also disassemble and clean the high speed needle valve assembly. You may have had a stray particle that came loose and got stuck in the spray bar. When this happens, the engine goes lean and overheats, loses compression, and deadsticks.

Brad