Originally Posted by TheShow50h

Mine runs perfectly fine on 87, but I run 89 to give me a little cushion most of the time just in case there is detonation that I'm not hearing while running 87.

The reason some people run 100+ octane is because that is how there engine setup was designed... some engine setups make way too much cylinder pressure to be able to run 93, so they need a colder burning fuel (for instance, high boost/compression/nitrous). Run a tank of 89 through your bike Jeremy and see how it does. The best way to test if it's running fine will be to put it in high gear and romp it from a real low rpm to put the engine under a lot of load, you should hear any detonation... you'll know it when you hear it.

Btw, your car, same thing. Unless your timing has been advanced you should be able to run 87 all day... remember, i know a little bit about the 5.0s and how to make them fast.