This is my first forray into cross bikes. I will be racing cx for the first time this year. I ordered a 54cm Fuji Cross through our team deal, which comes with 172.5 cranks. I am a Campy guy, so all the Shimano parts will be ebayed and replaced. The 54cm comes with 172.5 cranks, where my road bikes are 56cm with 175mm cranks. While I am replacing parts, should I replace the cranks with something I am used to, i.e. the 175's, or is there a reason to run shorter cranks in cx?