I seek out the CLEAN non-ethanol gas for my bikes and lawn mower. I costs a bit more but even the owners manual discourages ethanol.
The octane rating around here is 88 for the clear stuff.
It amuses me that people think that premium gas is better than regular. It is not. The octane ratings, if I am correct, determine the combustion temperature.
Thats why older engines (that ping) tend to run better on the higher octane gas. I can't remember all the stuff I used to know about Octane ratings but it is along this line.
I still user the regular 10% ethanol in my cars, though.