Saddle Chafing

I've been lately having trouble with saddle chafing recently and switched from a Specialized BG (originally on a hybrid) to a Sella Italia Flyte (came with bike, don't like the high middle section) and now have tried the Toupe (143, smoother), based on the recommendations of several fellow bikers and the forum. I've searched the forums but found nothing the same. The chafing I speak of is some vertical red lines at the very top of the back of my thigh, sort of where I think the edge of the saddle or Pearl Izumi chamois is when seated. It is right beneath where a wallet pocket on pants is and seems worse on the right side. Can saddle position (rocking?) cause such chafing and can the chamois edge contribute (seems unlikely to me, chamois looks ok)? Sit bones don't seem to be a problem, but the chafing is. I don't seem to notice when riding, just a few hours afterwards. Also, when adjusting the saddle up/down or front/back, is 1/4 inch a good increment? That what I've been trying. Thanks for any feedback and thanks to you members for all that I've learned lurking here.