Originally Posted by
carleton
I think everyone could have this odd dissonant RPM.
This could or could not be OP's issue.
I ride 165 cranks and I have experienced this around 135 rpm. I agree that this probably happens to everyone, just the frequency differs as a function of the various parameters mentioned by Carleton. Given my morphology, bike set up, etc, it seems that the rpm range at which to phenomenon occurs is relative tight. At 130 I don't feel anything, and at 138 it is gone.