85 thats some watered down shite. Run at least 89. Ideally especially in the heat 91 plus for optimum (timing advance) performance. You didn't buy a low compression economy commuter scooter. Its a high compression high performance to its size engine designed to take advantage of the higher detonation resistance of high octane fuel.
This engine has the components designed to withstand the corrosiveness of the added corn alcohol ie ethanol fuel. Naturally its ideal and you get more bang from your buck if you have access to ethanol free pure gas.