[TxTaoRider]

I'm gonna agree and disagree with some of the higher octane/lower octane/ethanol/non ethanol conclusions....
1st everyone is right, these low compression motors were designed to run on cheap low octane fuel. Higher octane tends to burn slower and could cause a very minor loss in power (but probably not significant). However it's resistance to detonation is probably a good thing with the overly lean stock jetting, which is more prone to knocking due to higher combustion temperatures.
Ethanol has a slight cooling effect but also requires more volume due to its lower btu which tends to make the slightly lean stock mixture act slightly leaner.
Lastly, whether it's true or not, most gas companies tout their premium fuels have more cleaning additives which if true should slow the deposit buildups.

Personally, I'd run premium with the stock motor until I rejetted for safety against detonation, and after rejetting I'd run whatever is available.