If everything is accurate, the correct amount to add is 2.1 oz. 2.3 oz brings you to around 23:1, so you're still really close. If it smokes a lot, you may want to try 32:1.
Keep in mind that regardless of the mixture ratio, the amount of fuel passing through the jets is fairly constant, so increasing the oil actually decreases the gas and leans out the mixture, causing the engine to run hot. Also, the oil burns hotter than gas adding to the problem. So you can actually burn up your engine by using too much oil.
I know it sounds wrong, but I got this info from an article in Cycle magazine written by Gorden Jennings, and he knows way more than me about two-strokes so I believe him.