You really don't want to leave gasoline with alcohol in any fuel system
for long, without at least treating it with some fuel preservative.   I've
been using Stabil now, which seems to work OK, but I haven't any long term
storage experience with  vehicles using it.
   You would not believe how ethanol gas can coagulate into such a
tenacious gummy messy substance if it's just left in a tank and fuel system
without any 'help'   I recently revived a couple of our dirtbikes which had
just been 'pushed aside' for about 6yrs.   These had gas/ethanol fuel in
the tanks (a KTM and a DRZ) and somehow, they were just 'out of sight, out
of mind) against a Ponderosa tree with covers.   I knew I would be
rebuilding the fuel systems after that kind of dumb neglect but I was not
prepared for the substance I found in the tanks....It was like hard gel
that was almost unaffected by any solvent that I found...   I had to throw
away the Suzuki gas tank it was so bad, and replace, not just clean and
rebuild, both the fuel valves.    The carbs took multiple multiple
cleanings.

   Now I am more careful with that crap.   If I intend to store any motor
for longer than a few weeks I always at least put some Stabil in the fuel
and run it into the carbs or injectors before I shut off the motor.   If I
can, I fill the tank with 'Non-Ethanol' gas, which is available in some
stations around the Northwest, and make sure to run that into the intake
system, again with some Stabil in the tanks, too.

   I have a friend who's in the motorcycle suspension business.  He uses
Stabil as a solvent for gummed-up motorcycle forks and shocks...I soaked
those two motorcycle carb parts in Stabil to remove some of the gummy mess
the ethanol left in there...It sort of works....better than MEK, Acetone,
or any other nasty solvent I tried at the beginning of my 3 full day ordeal
fixing my 'storage mistake' this spring...

  I wonder if Corn ethanol is any different than Cane-juice like they use
in Brazil?   Or sugar beets, which I am told is very much more effective as
a fuel source than corn....