What fuel is best?

[pliskin]

I'm a little confused as to what you are saying. You say you started with a full tank and ran it almost all the way down. If it ran OK there is no need to drain what is left. Just put gas in and go. I'm with the crowd that says higher octane gas is a waste of money. High octane gas is for high compression engines. The GS is not. In the US the GS calls for 87oct. That is the lowest rating. I don't know what that equates to in EU ratings.

On a side note do not use anything with a ethanol over e10. e15 is NOT GOOD for small engines. e10 or lower is OK but goes bad much quicker when stored for a long time than ethanol free fuel. If you have access to ethanol free gas (sometimes sold at boat marinas) use that. It's much better for your bike.

Just my opinion.

[Kookas]

I'm a little confused as to what you are saying. You say you started with a full tank and ran it almost all the way down. If it ran OK there is no need to drain what is left. Just put gas in and go. I'm with the crowd that says higher octane gas is a waste of money. High octane gas is for high compression engines. The GS is not. In the US the GS calls for 87oct. That is the lowest rating. I don't know what that equates to in EU ratings.

On a side note do not use anything with a ethanol over e10. e15 is NOT GOOD for small engines. e10 or lower is OK but goes bad much quicker when stored for a long time than ethanol free fuel. If you have access to ethanol free gas (sometimes sold at boat marinas) use that. It's much better for your bike.

Just my opinion.

That said, at least here in the UK, government regulations on renewable fuel here require ethanol in standard unleaded but not in super, so depending on the rules where you are, that higher-octane fuel may also be what you need anyway to get something ethanol-free.