all well and fine
87 here and 64mph out of a 125. so i am comfortable with my recommendation
so far as using what the manual calls for? its not always necessary or best. for instance my A125 manual calls for 15w40 dino oil. but many use synthetic. hell, maybe even most. and of different weights. and all that is fine, too. but not what the manual calls for and no harm is done. same with octane rating for gas.
the Kymco 125cc is the 150cc is the 163cc. Unless the FI system requires higher octane these small engines don't need it. does it make a difference in performance? for some, maybe. But for many others not
i used to use 92, too. but i went to 87 a few months back with no adverse affects. speedo hit 72mph the other day with 87. that fuel is fine and its cheaper. these are simple, small engines. they don't need "premium" anything. especially if their is even a small chance of higher octane fuel doing harm. lower octane certainly does no harm in my expereince
i also use the 15w40 dino oil. after all, its what the
manual recoommends