Re: Fellow Opti-2 users please help me out!
That's not too bad considering you're running a lot more gasoline in your mix, you want that light tan color like the same way a 4 stroke engine would be when tuned properly. The third picture looks ok to me considering the mix ratio and the amount of time on that spark plug.
The best and most accurate way to determine what your engine is doing would be to use a cylinder head temp gauge, these have a small washer shaped sensor that goes under the spark plug and they're very accurate, then you'd always be able to know if you're getting too hot. These engines will tend to produce a tinny sound and lose power when they get too hot as well, but that looks about right for running the 100:1 mix.