Running too Lean

Run through all the tune-related basics; tune-up parts and technique suggestions are in this post. Late ignition timing (either because the base timing is too late or the mechanical and/or vacuum advance systems aren't working correctly) is a short-list suspect for this list of symptoms. So is improper camshaft timing. So is a carburetor issue—sounds like you're not real sure about this carburetor and its condition. Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.