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Moonshine
09-12-2006, 10:47 AM
We've got a couple of new BMW motorcycles coming at work, and the manual indicates a recommended octane rating of 91 AKI. Does anyone know what the AKI means, and how that compares to the R+M/2 octane ratings that we're used to seeing on pumps?

Moonshine
09-12-2006, 10:49 AM
Disregard, I found the answer.

99WhiteBeast
09-12-2006, 10:55 AM
Disregard, I found the answer.

Can you share for us curious types:D

Moonshine
09-12-2006, 11:02 AM
Sure. What we usually see on pumps is the average of the Research Octane Number and the Motor Octane Number, displayed as R+M/2. AKI is Anti Knock Index, and it is synonymous with R+M/2, so basically BMW is recommending 91 octane fuel for these bikes, but they're injected and equipped with knock sensors to retard timing if a lower octane fuel is used.