Have read many posts on gearing choices, but I still don't understand some of the choices in gearing. I see recommendations for a 50x15 for the kilo, but a 53x16 is too big a gear. Why? aren't they about the same in inches? I mainly ride a fixed on the road, and pick my gearing depending on what group I am going with, or if I want to spin that day. I have no problem pushing a 53x14 when I go with the 'A' group on Saturday rides where the speed is 25-30 mph, and equally have no problems with a sprint of 165 rpm on a 44x16. The track that I am looking to ride on is the one in Miami. Any advice is welcome.