The thought of kidney stones makes me shudder. I have had about four of them with the last being in March. Mine have been tested in the past as being uric acid stones. I was told to drink at least 64 oz of water a day and stay away from dark sodas (coke, dr. pepper, etc). I wish I had more advice regarding hydration during cycling but your hydration schedule seems adequate. I hope it passes on its own for you though it may make you squeal when it comes out! My sister-in-law had a large one broken up and she passed small stones for days. Good luck with it because I know how excruciating (and frustrating) it can be.