I am leaning towards replacing the entire crankset. I am running a Truvativ Elita crank now with a GXP BB. I know (or at least I believe I know) that a Shimano crank will require a BB swap also, correct? Would it require anything else? I am going to look for a compact Truvativ in 50/34, but so far I only saw 50/36. I would prefer 50/34, but also want to factor in the cost. Thanks so much for the input....