I started hearing the metronome-like tick-tick-tick of the bearings down by my feet as I was biking to work the other day. The unmistakable sound of a bottom bracket gone bad. So I removed the bottom bracket to get the part number and measurements (how am I supposed to remember that it’s a Shimano ES25 with a shell width of 68mm and spindle length of 118mm?). Once I got the bottom bracket out, I was surprised the thing still spins at all.
It took me 10 minutes to clean it enough just so I could read the measurements inscribed on the shell. Lesson learned. Don’t be like me. Replace your bottom bracket before it gets this bad.