The only reason to increase your octane is to eliminate knocking. High octane does NOT increase power, run cleaner, or anything else. So if 89 doesn't cause knocks go ahead and use it.

 

91 being the minimum octane rating recommended, it also says in the manual that if you experience any problems to try a higher octane rating..so I'd personally rather err in higher than lower minimum rating...that does suck tho that you don't get 91..don't screw with the hassle of carrying octane booster and just run premium..have one less pizza out night a month and put it in a Harley fun piggybank!

 

I would check on that, to my knowledge the highest grade of conventional gasoline produced as of the beginning of 2016 is 90.5 and is sold as rec gas. I have a buddy who hauls gas for a living and told me about this almost exactly a year ago. I remember reading an article in The Oil Express put out by OPIS confirming what he told me. Every station I used to buy 93 ethanol free from has switched their pumps to show 90.

 

we're mostly still 92 here in Oregon

 

No madder how much you explain it many will still never figure it out. 91 or 93 89 it is not about better. It is about the point at witch a fuel ignites . If you put 93 in an engine designed for 87 it is not as good if you put 89 in one designed for 91 same result.
Your HD needs 91 if you can not get it 93 . It is not because one fuel is better or worst.
It is about compression and fuel igniting.
Run 91 in all my Hd's I prefer non ethanol due o mileage but 10% works just fine never any knock issue.

 

So many things wrong with your post. I never said the manual calls for 93, I said it calls for premium. 91 octane is premium. Get it?

You said "I'm retired and yeah an extra $6 or $9 bucks a day or more matters to me".... You just contradicted your main point. If you're retired and need to pinch pennies to the extent that you're wanting to use mid-grade gas, what the hell are you doing riding the bike enough to have to fill it up every day, or more?

 

My manual specifically calls for 91 octane. "Premium" isn't mentioned anywhere. But that's meaningless, just pointing it out.
As for my riding habits, the great part of not having to work everyday is being able to jump on the bike and ride ALL DAY. Even multiple days! If I wanted to just cruise around town for a couple of hours I've got another bike for that.
Maybe I made it sound to you like I'm too poor to ride, that's not the case. I wanted opinions from forum members about what works and what doesn't, and I've got some good input. Yours, not so much.

 

Other areas may be different from the SouthEast. We still have 93 but it has ethanol in it. A call to the petroleum supplier will confirm the highest grade of conventional gas (non-ethanol) available in your area.

 

Not to hijack but our highest R+M/2 octane gas is 91 and contains no ethanol. I'm wondering if dropping the ethanol from higher octane grades of gas is a general thing or just a regional one ?

 

Where I'm at they just add 10% across the board. It's probably regional because it's a winter thing. Or actually a Government program. I don't want corn alcohol in my gas!!!! Lol.