I am building a bike and I am using a saddle with carbon rails on an alloy seatpost. I read that it's not an issue as long as the shape of the clamps is compatible with the shape of the rails, and in my case it is.
However, the torque specified on the rails (6 Nm) and the torque specified on the post (12 Nm ~ 15 Nm) don't have any overlap. Which of the two should I go with?
I am afraid that if I go higher than 6 Nm, it will damage the carbon fiber of the rails, but if I go lower than 12 Nm, the saddle will slip while I ride, and as a consequence will again damage the rails.
Should I ditch the combination all toghether? Or something in the middle, say 9 Nm, is going to work just fine?