Ignition timing versus 98 octane gasoline

[WojtekPoland]

Hi everyone
I wonder should I set ignition about 5 deg. earlier because of using 98 octane gasoline. My bike is BSA A65 Lightning 1968.I do not know wat was gasoline octane number in UK in 1968 but in Poland was 78 octane.
Thx for any answer
Best regards Wojtek

[DAVE BRADY]

Hi Wojtek,


I run a '68 Thunderbolt at 34º and it is fine with today's fuel. I also have a long stroke 750 A65 and use standard A70 timing of 38º.
Start with the standard timing of 34º BTDC fully advanced and see how the bike runs. If necessary retard it a bit to get better running.

Dave.