Thanks guys for the feedback. I have used the Cabela's semi-syn for years and it seems to work fine. However, I haven't done a compression test for a number of years so I guess I don't know for sure. It's still running...
One of the other reasons, I ask, I was reading on one of the fishing forum sites where guys were talking about an adding an additive into the injection tank which cut down on the two stroke smoke as well.