Hi All,
Whilst the handbooks may state a specific figure for the ignition timing - that may not be appropriate for running on modern fuel. I would suggest it is better to time up the ignition about 5 degrees earlier - then run the bike, adjusting the advance/retard until you find the 'sweet spot' at which the engine is at it's happiest - check what the advance is, and re-time the mag to that figure when at full advance.
Regards,
Eddie.