My bike never makes noise. But now it is. Ugh.
My left crank makes noise, once per revolution. It's not the chainring bolts; they're snug. My crank is not loose on the spindle; I've made sure the bolt is tight. It's either the interface between the crank & the bb spindle (square taper... may have rounded the hole a little... it wiggles a hair), or the bb itself.
Have to take it apart now and see. Good thing I don't mind working on bikes.
Buying parts, on the other hand, I can do without.

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