Lol...some of those E europe bikes were probably tuned to run on Vodka or Slivovitz(a). ..😄Been using e10 when riding around the continenent for years. When the switchover happened here in the UK, I used it straight away (actually, most of the stations switched to it a month early!), and i've had no issues with running e10 on any of my vehicles, and only 1 of my 8 vehicles is YOUNGER than 1991.
Hi,It is best not to leave E10 in a tank or carburetors during storage. It absorbs water. It can cause 'varnish' in the carbs. In the United States we have a product called Sta-Bil that we add to the fuel and run it through the carbs before winter storage (in the northern states). There are other stabilizers but Sta-Bil seems to be the most popular and readily available.