The real problem is if you have a plastic tank made by Acerbis ( Guzzi, Ducati, Triumph and my bloody Cagiva) then the ethanol drags water in which makes the tank swell, my Elefant tank grew so much the rear tank bolt was half inch out from fixing. For metal tanks the problem is if the bike is laid up for any length of time, attracts water , rust, gets in carbs etc. There is ethanol free fuel available From Aspen fuels that you could put in before laying up a bike and it should fire up a year later no problem, but we?ve all left bikes to stand without draining tank etc. I don?t think I would bother trying to remove ?some? of the ethanol with a kit , then you?ve got to dispose of some yucky water.