Most likely, your valves are out of adjustment. I know, what valves..... While you are at it, clean the engine block cooling fins. Remove the engine shroud. Look for grass, oil, mice, dirt dobber nests, grease, or any other filth around the fins. Look all AROUND the cylinder/s. Over heating can lead to valve seats popping out and so on.I charged the battery up to 13.2 volts. It dropped to 10.3 after starting with cleaned cables and using dielectric grease. What does that mean? Thanks for helping
slomo