Motorcycle Repair: 1980 2000 milles cm400e engine ping, timing advancer, combustion chamber

Question
I asked a question about my sudden engine pinging which was answered either oil getting into cylinder or timing is off
how do I diagnose it? the bike is not smoking, wouldn't it smoke if oil got into cylinder?  15 minutes prior to the ping I filled up with gas at the pump about 1/2 tank to max with 87 regular could that have cause the pinging?
and last if my timing all of a sudden got messed up how do I tell?

Regards

Eric

Answer
This bike has an electronic ignition which is not adjustable and is probably not the cause of the problem. I didn't notice a timing advancer on the microfiche. The only things other than timing which can cause pinging are:

* using the wrong temp spark plug
* using low octane fuel
* carbon buildup in the combustion chamber which can cause increased compression

Are you sure what you are hearing is pinging? Do you notice it when you quickly open the throttle in low gear? That's somewhat normal. If you hear it whenever to open the throttle or while cruising that's not normal.

You can try pumping higher octane fuel to see if this helps.