Modern Buddy

Sometimes when I am far from home and about to run out of gas, I will fill with the higher test regular (ethanol) gas. When I get home again, I start right off filling with 91 octane ethanol free gas. Any harm done ?

why do you fill it with a different octane just because your far from home? If I recall the manual suggests regular 87 octane doesn't it? I don't know if your harming it or not.

Octane and ethanol have nothing to do with each other. Avoid ethanol if you can (its rough on small motors and collects water). As far as octane- if it's still stock it will run on anything 87 and up. There is a slight difference in performance but not enough you'll be able to notice on a 50cc, and you would have to adjust the timing to get the little tiny bit of power you can squeeze from the slightly higher octane. With 2.5 hp your tire pressure matters more than octane. That being said, ethanol free gas runs better than ethanol gas (more btu's per gallon).

I am not so concerned with the octane as the ethanol, so let me phrase it another way.
If I have to upon occasion fill with 10% ethanol gas, will it have any detrimental effects if I return to ethanol free gas as soon as convenient?

dusty roads wrote:I am not so concerned with the octane as the ethanol, so let me phrase it another way.
If I have to upon occasion fill with 10% ethanol gas, will it have any detrimental effects if I return to ethanol free gas as soon as convenient?

There will not be any long term issues, particularly if you regularly ride the scooters . I don't have any ethanol free gas stations near me so I only use gas containing ethanol and my 50cc scooters run fine (as did my 170cc Hooligan before I sold it and as do my two Piaggio MP3s). If you have worries about it, use a little bit of the fuel treatment products that prevent ethanol build-up in your engine and fuel system.

The reality is that the vast majority of scooter owners probably never put ethanol-free gas in their bikes and they have no problems.

Thanks, cummingsjc, that helps..

Has everyone seen these web sites? If not, I hope it helps..
https://www.pure-gas.org/