I regularly stick all sorts of 'shite' fuel into my awesome steeds. It hasn't yet brought about the end of the universe or even, me. There again, I ain't been to Hilltop; should I go?
I've avoided E10 after hearing scary stories (no idea if it's bollocks but didn't want to chance it) - we had some sustained 130kph motorway runs so I also wanted to avoid the potential burned valve thing you hear about (possibly bollocks also).
There is some truth in it but like anything it depends on many factors including how you ride, Ethanol has higher knock resistance than petrol but it has a lower calorific value so you end up needing to open the throttle more and the injector pulse widths will need to increase to discharge more fuel in.
So any fuel with Ethanol in will require the ECU to recalibrate so its entirely forseeable that the engine could run lean to a point of causing problems particularly if riding aggresively.
Fer Gawd's sake yer average bloated Corporation can see the likes of some of you lot coming a mile away.
Put some go juice in and ride the bloody things and stop getting all 'princess and the pea' and paying more for stuff that gives minor, usually undetectable benefit.
Use the money saved to bolt another piece of shit to the bike