RE: Brillelli 366GT *60cc*
Scott likes 40:1 all the time, and that's all I've used in all my Brillelli's. I personally use Pennzoil Outdoor Equipment at 40:1. Scott likes Opti II or whatever that is, but I don't think he recommends a specific brand. It's a Husqy chain saw jug, so any good chainsaw lube is probably fine. On one of the early 40's I had, I used Stihl, it seemed fine too. These motors are not "picky", and just like adequate oil, and not too lean a ratio.