All those other oils named above are just fine -- as is
Amsoil 5w-40 (used by LOTS of bikers...look for a local Amsoil dealer) -- but I decided to "go Italian" and ordered some
Agip 5w-40 synthetic from America Agip:
http://www.americanagip.com/
You can't buy less than one case (can't order just a couple of liters), but I wanted a case anyway. And, of course, they have other oils for Vespa needs. Shipping is high, but fortunately, I don't have to buy a case very often!
Good luck...
⚠️ Last edited by cloudcroft on UTC; edited 1 time