For any given setup colder plugs and/or higher octane fuel will ward off detonation.
The bike just needs setting up to suit the fuel it's running and plugs that won't melt but there's going to be a max you can push it to (ignition/compression wise) for a given octane.
Hence you just can't get a '28 on an 010 card or a '21 on a race fuel cdi to stay alive on anything other than Avgas or proper race fuel.
I wouldn't have thought a normal full power NSR is ever going to be that happy on 91ron and BR8ECM's, road or track.
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