Ethanol is more volatile than octane.
You're going to need something to THIN the remaining gas, not thicken it.
I’m not sure that volatility is the property of particular concern and not following what you mean by “thin”.
True, the chemical ethanol has a higher vapor pressure @20C(and octane rating) than the chemical octane but I don’t find a direct relationship between volatility and octane rating (toluene has a lower vapor pressure @20C than ethanol but a higher octane rating).
Pull the 100 +/- octane (R+M/2) ethanol out of E-10 blended regular 87 octane fuel and the octane rating of the remaining gas is less than 87. So, you need to replace the ethanol with something that has a higher octane than the ‘bare’ gasoline, in the proper ratio, to achieve the desired total octane rating of the ‘re-blended’ fuel.
Carb, why don't you just add an inline petcock to the ruckus?
Just doesn’t seem worth the hassle. The tank is under the floorboard with a close-coupled electric pump and a short hidden hose to the carb. The darned thing is reliable as heck and starts fine after sitting 30 days +/- between races where it’s used; I think I just gotta get a better storage/maintenance routine for the bit longer off-season, like taking it out for a play ride every once in a while to move the Stabil-ized gas through the system.
If you’ve put a manual petcock on a Ruckus 50, I’d like to see a pic, though. You can email me through this forum.