I did not read all the gas posts... sorry. Did not see this specific scenario, tho

My local stations, I live very rural, have only the options listed in the title. I can get 89 pure gas at one station... he only carries 87 and 89. 91 at another station... which accepts credit cards. Just curious which would be my best option. I usually factor in how soon I know I will ride again. A day or two, I get the alcohol gas.

On my ride today I got 91 pure gas in another town. Just getting enough runs to compare mileage on the two options. I would rather no ethanol, but my book says 91 octane..... so

 

I would go with the pure gas, wish I could get it around here.
Especially for that last fill up of the year before storage.

 

I generally won't use less than 92 in mine. Have had to make due with corn gas in KS but worked at finding straight gas as often as possible, I would stick to the higher 91.

 

Take a look at this website. I use it all the time.

http://pure-gas.org/index.jsp?stateprov=AR

 

Do you want "6" of something or a half dozen instead?

 

The higher octane of the 91 is more important than the lack of Ethanol in the 87 grade.
10% Ethanol is not going to hurt your bike at all.
I would use 91 or higher all the time, Ethanol or not.

 

Why don't you run a tank of each and see which your bike prefers. On a road trip last year I got "stuck" using 89 pure and it was the best running fuel of the entire trip.

 

Octane rating indicates resistance to spontaneous combustion without help from the spark plug. Compression creates heat, that is how a diesel engine works. The amount of heat generated depends on compression ratio and the amount of air getting into the cylinder. Because no conditions are given in the manual, you can assume that 91 octane is good at sea level. The higher above sea level you go, the less air there is. The less air there is, the less heat is generated by compression and the less octane is needed to prevent knocking/ping/pre-ignition. Experimenting with 89 octane won't hurt anything, at least for a short time. If you run your machine down fairly low on fuel, you can put in a couple of gallons of 89 and try it. If you don't get any ping, 89 will work for you at that altitude. If you do get ping, top off with 91 and that should minimize the pinging until you again re-fill with more 91. I live in the Oklahoma City metro area and 100% gas is still available here. The elevation here is about 1300 feet above sea level and I have been using 89 octane for several years and it performs very well with no ping.

 

I work for the local PD here and we've had a lot of problems with our vehicles. One of the techs at the city garage told me that a rep from GM came out to meet with them, and they have been doing the same with many other large cities around the country. As part of their investigation into the problems they've been collecting fuel samples from the vehicles. He said they've never found 10% ethanol in the vehicles. The lowest they have found is 11% and the highest was 31%, with the average being 19%. He claims that is part of the problem with the sensors on the new flex-fuel vehicles. The ethanol content is so high in the fuel that the vehicle sensors think it is E85 with low ethanol content, thereby setting off the fuel system warnings. I just picked up some Startron and I'm going to start running it in the tank. Rather be safe than sorry.

 

I have been alternating. I usually tank up a bit under a half tank. Have been told keeping it full leads to less condensation/water in tank. So I guess I have been running a mix. I would gladly use the 91 pure if i could get it.

I have noticed no running issues and minimal if any mpg diff

Sometimes know when I can get out again, sometimes not. May be a week tops between rides. Rarely more than that without at least a 40ish mile lake run