I had exactly this problem with the B17, in the same spot (the "adductor insertion into the inferior pubic ramus", according to my lady chiropractor, who checked me out when the area was still red and tender).
I don't know my measurements but after some trial and error found that the B68 is perfect on my mixte (upright position) whereas the Swallow is *BLISS* on my Surly Pacer (roadbike).
Good luck!
Rebecca
Riley - custom 2014 Enigma Etape
Bridget - 2010 Surly Cross Check
Lorelei - 1979 Puch Princess mixte
Astrid - 2014 Viking Bromley singlespeed mixte
Lucy - bespoke 2012 Brompton S1L
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