Ive seen many Bike racers , go buy a new bike and rip off the efi and go back to carb
E10 holds around 0.5% water per liter, that can build up in the bottom of your tank over time and Servo,s for that matter. Many Servo,s have destroyed new car engines due to water in fuel especially towards the bottom of their huge tanks. And new car warranties dont cover that.
As for water in your ethanol or fuel , wouldnt hurt to flush your tank once in awhile.
And to remove water from Ethanol is simple without distilling.
Example : get a clear bottle with lid. Like a 4L water bottle . Add 20% salt / Liter of Ethanol and shake . ( The salt cant have Iodine ) It will go cloudy and bubble. Usually when bubbles stop which comes 1st. Let it sit and you get 2 layers for few minutes. Top layer is alcohol. Dont do it on a cold or wet day . As Alcohol can pull upto an ounce of water from the air in minutes.