Well, he’s 10, and he’s been known to say “Dad, my motor sounds weird.” Honestly, you could probably get by with 89, As Rotax are pretty low compression engines. I like the idea of race gas; consistency, smell (not important, but nice), and doesn’t leave your carb sticky with ethanol residue. I’m sure it’s easier on the motor, too. But we’ve always had much better performance with pump gas, so pump gas it is when we can use it.