Having excess octane is safe and won't cause problems with jetting, not having enough octane or unknown quantities of ethanol mixed in is not safe and jetting can be impossible to fine tune.
Your choices are AvGas, race fuel, or set your quad up to run straight alcohol or E85 (it always has the same amount of ethanol).
It is still possible to find a gas station that sells straight gasoline, and it'll be more common to find it in the months and years to come since the corn/ethanol mandate is running out of steam.
I recommend AvGas at a minimum (100 octane) or race fuel (100 octane or above), especially if you haven't fixed the cylinder head geometry.
Running pump gas in a zilla is pretty much a sure-fire way to ruin it.
When you run higher octane fuel that is always the same consistency, you can jet it more reliably...so if you're doing ok with pump gas then you can probably lean it out a little when  you switch to race fuel.