I have a 2008 Cannondale Bad Boy Ultra with about 3,000 or so miles on it. When I pedal, it makes a ticking sound at the same area of each revolution. It only makes this when there is tension/force, not if I have it on a bike stand or if I pedal with little force. I tried pedaling with one pedal at a time to see if it was in fact the pedals themselves, but it still happens. It does this in every gear, and I have a new chain and cassette on it. The chain is not rubbing and I can't see any parts that are making contact. I'm thinking it is the bottom bracket. First question is, do people think that is likely the issue given the information? Second question is, how do I know which bottom bracket to replace it with? I know the one that came with my bike is an Shimano BB-ES25 Octalink, but I'm not exactly sure what size or how to determine that. Also, what is a better quality bottom bracket that I could replace this one with? I think a bottom bracket should last much longer than this one.