You must be pinching a nerve. I would not worry to much about it. There is a nerve that runs .......hmmmm how to describe without getting too graphic? Ok runs along your pelvic bone on either side. Your seat might need to be changed to maybe slightly softer, adjust the seat hear and there. And it probably doesn't bother you right away because things take a bit to get heated up and swell up. Does that make since to you? I would try for now moving around a bit on the longer rides till you can get it figured out. I don't know if getting a thicker short would help? But this might be a matter of elimination. Good luck let me know if you do get it figured out.
Blessed are the flexible, for they shall not be bent out of shape.
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