Pat--you ride a VN1500, it appears. Isn't the recommended fuel for that bike 87 octane? If that's the case, then it makes no sense to run higher octane fuel in it anyway. At least that has been my experience running premium fuel in any engines designed for regular 87 octane.
Now my '10 Nomad was recommended to run on premium fuel, but when only 87 octane was available, as is often the case in some of the small communities, it seemed to do ok on that.
Well, we've gone around and around here on octane and fuels. What I've discovered after looking into it is that from the factory, my '04 Classic owner's manual recommends 91 0ctane fuel. However, that's using the Japanese and European method of octane calculation, which is usually the RON method. (Research Octane Number). There is also a MON (Motor Octane Number). The RON is a lot higher than the MON, but are nearly identical in ACTUAL ocrtane . In the US, we don't use one, we average them both. That's why on the pump it says "87 octane (RON+MON/2) Octane rating is simply the speed at which the fuel burns to prevent pre-detonation in high compression engines. lots of guys think it's somehow a better grade of fuel, but it isn't. It's simply designed to burn slower and thus not as hot, which on a bike set up lean from the factory is warranted. But once I opened up the air, pipes and so on, 87 gets me better throttle response, better mileage, and certainly lower cost.
In the US they take the RON number of 91 for regular, add the MON number of somewhere around 83, and average it to get 87. They are basically the same octane rating. In other words, 87 octane is 91 in Japan and Europe.
Here's an article that explains it better than I:
http://www.economist.com/blogs/babbage/2012/09/octane-ratings