I use 93 when I'm running on the street. I use it because I have high compression and I'm mapped for it. I run Sunoco 112 octane on the track with a different map because it gives me a bit more HP, (with high compression), the bike runs cooler, and a little smoother throttle response. (Could be the map though LOL)
Turbo bikes can use low octane fuels because they usually run lower compression then stock so they can pump more boost into the motor.
The lower the octane fuel the hotter it burns and the more HP you get. Higher octane fuel burns cooler and more efficiently, but gives less HP.
On another note: what mostly matters is how your bike is mapped and how it's built as to what fuel gives you the best performance.
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Do you really have to start a thread every time you go on a ride and see a guy with no helmet on?
Does it affect you that much that some random guy 1500 miles away went and paid his own money for a 1000?
Do we really have to fight over who uses the back brake or not?
Do you have to argue over stupid pointless shit on the Internet?