Originally Posted by
cny-bikeman
Unfortunately it's likely the solution was overkill. When a BB is replaced it involves removing the cranks, cleaning mating surfaces, then tightening both the BB and cranks to proper torque . If the underlined steps had been done (in addition to same on the pedals) the click would most likely be gone. It is also very rare that the BB itself is the cause of a once-per-rev click. For that reason I would respectfully disagree with Andrew about a pedal replacement. Having the click disappear with new pedals means that either the pedals OR their mounting was the cause.
Note: Replacing or lubing either chain or cassette would have been the wrong solution, as they rotate at a different rate than the cranks. If either was replaced to attempt a fix it's the work of an incompetent "mechanic" just throwing parts at the bike. Of course the chain apparently needed replacement, but it's unrelated to the noise.
I'll agree with this. But it's hard to separate the pedal condition from it's mounting in the arm. Sure one can stress the pedal in various ways, maybe with a stethoscope placed in various locations to try to locate the specific spot of the click. But a far quicker and more comprehensive test method is to replace the pedals. If the click is gone then remount the original pedals (with proper thread lube and torque) and see if the click is gone.
I also agree with the high goal to not only "fix" the problem but to also understand it completely. But most just want a quiet bike and don't care why that's the result. Andy.