So I've got a hybrid with a cup-and-cone BB that makes a click noise every revolution, generally when my drive-side foot is at the bottom of the pedal rotation. Took off the crankset to eliminate any issues there; it's in perfect shape. I've just recently replaced the 9-ball retainers with 11 loose ball bearings on each side in hopes of eliminating this annoying noise. The bearings are new, and show no wear at all. Greased OK, and no bearings are out of place. When I spin just the BB spindle by hand, either w/ my wrist or by rolling my thumb/fingers over it, there's no play, and it still clicks.
So, where the heck is the noise coming from? It was there before I replaced the retainers w/ loose bearings, and seems to have actually gotten worse since then! I'm completely and utterly stumped. I've checked everything. Seat post, pedals, derailers. The only thing I haven't done is to tighten the fixed cup, but it seems to be in there as far as it can go.
Shot spindle? Shot cups?
Thanks for your time.