[tubman]

I would start with a compression test, since you seem to be able to handle that yourself. The ignition? Unless you have the tools and experience in working with these, it is best to send it out someplace to have it checked, repaired (if necessary), and the timing set. Also, you can do a simple check by looking down the carburetor and see if it has a healthy squirt of gas from the accelerator discharge nozzles. There can be many things that can go wrong with these carburetors (leaky needle, leaking power valve, bad float setting, just plain dirty etc.). If you have the skill, you can go through the carburetor yourself, if not there are guys out there that are wizards with these and won't break the bank. A compression test would be a good first step, if only to ensure that there are no serious problems with the engine.