I followed Brad's instructions to a tee with my brand new Dax GT50R. I was all set to see the benefits of Opti-2, had even read this whole thread (which is why I tried it to begin with). But like the earlier post about hitting the thumb with a hammer, I now have a new seized engine from using Opti-2 at 100:1. When I kindly and patiently explained to Brad at Interlube what had happened, he quickly ended the call, leaving me to fend for myself. Cannot use what makes the engine seize. No Brainer, fanboys notwithstanding.