Opening a needle farther doesn't hurt a thing. It will just make the engine richer. You'll need to lean it as the engine is run in. many times, a final setting is close to 1-1/2 turns out from closed, so we usually recommend opening it a bit more and going from there.

You can go to the O.S. FAQ page at the O.S. website.

http://www.osengines.com/faq/index.html

A lot of info there!