hey I'm a junior racer and want to run a 45x12 as my junior gearing instead of the traditional 52x14 so I don't have to keep swapping out my cassettes...I've heard of ppl running this 45x12 but haven't actually seen it put to much use in my local races. Does anyone know who makes a 45t option for a big ring that is compatible for 9 or 10 spd gearing?