Some of the gas stations in my area have dropped 91 octane in favor of 93 octane (more profit?). Am I better off dropping down to 89 octane or bumping up to 93 if 91 octane is not available?

 

Try the 89 and see how it goes. I would probably use the 93.

 

I always run 93 when I can get it. There are times when some stations only have 92. Bit I prefer 93. I would go to 93.

 

use the 93; 20 cent difference x 6 = $1.20 bike will run better with the 93

 

Might get a little pinging w/the lower octane - I'm altwys hunting for higher so 93's my choice, or carry octane boost & add when filling.

 

91-93 is not going to make one bit of difference in your HD.
Octane , The higher the the number the slower it burns Higher the compression the slower the burn you need.
93 will not make your bike run one bit better just a mind .....
Those that have bumped up compression a bit may need to run 93 but for most just gas it up and ride.

 

The combustion process is most efficient and complete with the lowest octane you can burn without any detonation. You can burn 93 but if she will run on 89 without pinging, there is no benefit in running on 93.

 

Run the 93! That's all I ever run in mine unless I'm in the ghetto and they only have 91.

 

You guys are lucky. Here in the Republic of Kalifornia we only have 91. There is a station about 20 miles away that sells pump race gas. The highest is 99 or 97, I think. Whenever I near there I stop by. At $7/gal it is pricey, but the bike loves it.

 

Right before I put my bike up for the winter, I add a gallon of 110 octane to the tank, 4 gallons of 93 octane.
There isn't any breakdown of the fuel during the winter months.