if you feel like you are riding as fast as you can on that gear then lowering your gear will increase your top speed. I ride an 86" gear and I can pretty easy hold 20-22mph on the flats, spinning out at 37 on the downhills. I can average the same speeds with a 75" gear, too, but I spin out at 33 or so. You're way the hell up there in gearing.... I don't think that I could push that gear effectively at the velodrome, even. my intuition is that you would find a new enjoyment in biking with something like a 77".