I was chatting to an old school scooterist today, and I mentioned that I was using 4% on my Lammy. He said he thought it was too much, so as I had to fill up anyway, I used 3%.
Not thinking it would make much difference, I set off home and remarkably top speed increased at full tilt on a flat road with no headwind.
I couldn't say it was the oil, but performance did seem improved, without any tinkering by me ( been jetting).
Now can oil to fuel ratio make a difference, or did I just plumb lucky?