hey I was wondering if anybody could help me? Im trying to work out the difference between all the cyclocross bike gears some have shimano tiagro and some have shimano 105,what do they all mean? i understand that some a more racy gears where as some are more built for hills, I want a bike that can go really fast and allow me to get up hills ok. At the moment I ride a basic mountain bike (no susp.) and can cycle up any hill without stopping but I would like to go faster on the flat,thanks alot