Hi, I hazard a guess that, if the pedaling action is more angular with the pivot, the bigger the portion off the force is that will create the psi. Psi is also an issue of the right pedaling technik. Pushing the feet parallel to the wheel rather then directed at BB center will compensate a lot off the psi. As will the appropirate use off click-pedals together with a push pull pedaling technik. Gerald -----Ursprüngliche Nachricht----- Von: "Dirk Bonné" <dirk.bonne@xxxxxxx> An: python@xxxxxxxxxxxxx Gesendet: Donnerstag, 05. April 2012 09:45:11 GMT+00:00 Betreff: [python] Re: BB-seat diff vs. PSI