I think what MikeyD was saying was not that it burns at a different rate, but that gasolines resistance to preignition increases as the octane increases. He's on the same page.
Good information there Grinch and welcome to the board. I have one question for you (bear with me its a little long). If octane is based on compression only, then the ability to acurately test the octane vs. the compression would be a moving target wouldn't it?
My reasons for this train of though is that a 11:1 compression ratio at slow everyday riding speeds would never generate the higher internal temps that a 11:1 at full race pace (say roadracing). With that being the case, why would you base an entire fuel rating system on a moving target (internal heat) even though it has a fixed value (11:1 compression).
Wouldn't it be a better way to rate gasoline octane by the temperature that it actually ignites at? Really, who cares what the compression is, because a high compression motor at its coolest could be cooler than a lower compression motor that you are running the crap out of. It doesn't change the fact that if your motor is knocking the octane needs to be increased regardless of your compression.
I understand that for the consumer it is easiest to just quote a compression ratio, but on the engineering testing level the actual temp at which the fuel ignites would be more precise.
Keep in mind that I am not a fuel expert in any way, and I am not flaming or hacking, I am however curious. Don't be afraid of sharing your fuel knowledge, it is much appreciated.
Ride safe,
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