I am pretty sure i am hearing some pinging but my timing is set about 1MM after top dead center just to make sure i am not advanced. .
Black soot inside the exhaust pipe, or at least blackish. Not black smoke.
That static timing thing may not get you anywhere. One mm after TDC or 0.8 mm before may each get you into the ballpark. You can already start the engine so you can also dynamically check the timing. Peter
... The iron engine goes to full advance, anyway, very quickly. And the average rider is not going to be able tell if his engine is static timed correctly or "ping" timed as far as performance. And if the centrifugal advance is sticking and doesn't go full advance - and the engine is "ping" timed that way - what happens when it "unsticks" while riding...