By Lennard Zinn
Although sometimes difficult to diagnose, a creaking sound coming from your bike is always caused by movement between two parts that are supposed to be tight against each other.
Could that annoying sound be one of the rotors rubbing? ….
It used to be that a cause of creaking was often the interface between the quick-release skewer and the fork. With through axles, that’s less likely. It’s still worth first checking that the through axles are tight. If they are, remove the through axles and grease their threads and under their heads and tighten them up again.
If not the wheel axles, try first seeing if it happens while you’re standing out of the saddle pedaling to eliminate the seat post and saddle as possibilities. Next, pedal with no hands or with very little weight on your hands to eliminate stem and bar as possibilities. Then try switching to another set of pedals (and shoes, if necessary) to eliminate those as possibilities.
If none of these things eliminate the creak, then you’ve probably isolated it to the drivetrain. Things that can creak in the drivetrain are:
-chainring bolts: check tightness, and, if tight, greasing their threads and seats can eliminate a creak.
-left crank arm moving on the spindle; make sure the crank bolt(s) are tight.
-bottom bracket threads; this requires removing the cranks and bottom bracket cups, greasing the threads, and tightening the cups.
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