the bottom bracket on my fixie makes multiple clicking sound, similar to that of a stiff chain link, especially when i bear some weight down whilst pedaling. i know it's not the chain because that's well-greased and the same sound is present even with the chain off. the bike is a conversion... 70's french road frame with cup and cone and a campy track crankset. could it be bearing related? wondering what yo'll felt it might be before going to LBS. thanks.