I have been using 87 octane in my bikes for years with good results. The octane rating does not matter as much as the additives.
MTBE is part of the summer blend here in Phoenix. It is there to help prevent smog.
Methyl Tertiary-Butyl Ether (MTBE) is part of the summer blend here in Phoenix and hits the pump about April through October. Our pump fuels also contain ethanol. Both of these tend to make my bikes fun like crap.
Below is an excerpt from Fuel Testers . Com,
http://www.fuel-testers.com/mtbe_ethanol.htmlFuel that did not contain ethanol had a shelf life of several years; Unlike ethanol-blend fuels which remain stable for a maximum of only 90-100 days.
Test results on ethanol blend fuel shelf life were performed under ideal conditions (70 % humidity, properly sealed fuel system, lack of presence of rain/snow, etc.) - Therefore it is safe to assume that the shelf life and stability of fuels containing ethanol is much shorter than 90-100 days.
I found that using a fuel injector additive to my gas about every fourth tank made a significant difference. My bikes were my primary transport and were in daily service. Down times of over a week created issues during the summer months. This is why I switched to aviation gas for bikes that were to be out of service, as I posted earlier.
I would look at the ethanol content of your gas and think of it as High Fructose Corn Syrup...great for candy, not so much for gasoline.
JohnBoy