I just wanted to clear this up for a few people, because I was wondering about this as well. And after asking the right technicians and engineers for some of these bike engines I have a simple answer.

If your bike requires you to put high octane fuel in your Motorcycle (or car) then you shoudl stick to high octane fuel. If you put lower octane fuel in that same bike then its performance will deteriorate. Certain engines require high octance fuel.

If you have a motorcycle that you have been fueling with normal octane its performence will not improve if you put high octane fuel. Some people have had the false idea that the motorcycle’s performance will improve if they go for the higher octane, but it wont (that goes for vehicles too).

Certain engines are meant to run with certain parameters in mind.

Like this motorcycle the BMW R 1200 GS is meant to be a bike that can cross the globe, and so its engine is meant to take different grades of fuel and still perform. Its a powerful engine that will always perform, but they had remote areas with low grade fueling in mind and the bike is very powerful.