I’m in the same position as you. One of my bikes calls for 90 octane, which automatically pushes it up to super unleaded. I‘ve researched it, and best I can tell it it’s a CYA for the manufacturer for worse case scenario. No different than oil spec in my truck that calls for 5w20 to cover the cold northern states when a heavier weight would work just fine here in warmer Texas. In motorcycle forums I’m a member of, folks have run regular 87 octane without any issues. The newer bikes all have computers that can retard or advance the timing as needed, so I’m thinking that unless the bike is under extreme duty with heavy acceleration, then 87 might work. For sure, I’m going to run mid grade on my next fill up. I don’t see that 1 octane would make much of a difference. If it starts pinging, then I’ll go back to premium. FWIW, I had an SS Silverado years ago that called for super, but regular could be used with a hit on performance and efficiency. Truthfully, I couldn’t tell a difference so I just ran the 87.Gas prices are stupid and I don't want to be the same so, a little help please?
What could happen if I ran 89 octane gas in my high octane inline 4 bike with 13:1 compression?
Obviously I'll simply ride less if the risk is too high.