For the cake: Preheat the oven to 325 degrees F. Generously grease and flour a fluted 10- to 12-cup Bundt pan.
Beat the granulated sugar and butter together in a bowl with an electric mixer until creamy and smooth, about 2 minutes. Add the eggs one at a time, mixing well after each addition. Stir in the flour 1 cup at a time, blending well after each addition, until the batter is smooth; stir in the lemon extract. Mix the lemon-lime soda into the batter and pour into the prepared pan. Bake until a toothpick inserted in the center of the cake comes out clean, about 1 hour 15 minutes.
For the glaze: Beat the confectioners' sugar, milk, lemon-lime soda and extracts together in a bowl with an electric mixer on medium speed until the glaze is smooth.
Pierce holes in the cake with a skewer. Pour 1/4 cup glaze over the cake. Flip the cake onto a serving plate to remove from the pan, then pour the remaining glaze on top. The cake can be served immediately, but tastes even better the longer it sits.