I have a [VNT Elements Seat Post] (https://shop.vannicholas.com/en/products/vnt-elements-accessories/VNT-Seatpost-Alloy-16-7mm-Setback/11326). This saddle has two bolts at the back and clamps onto the seat post on top. Van Nicholas also makes a titanium seat-post which clamps from the side and has special carbon saddle adapters for the titanium saddle. I assume that my saddle is compatible as no separate adapters are sold and, this is just a top-bottom clamp.
This seat post worked fine with my Montague Saddle with steel rails. I have now purchased a Brooks C13 Saddle with carbon rails and find that the rails are slightly closer together.
That said, I had a few questions,
My local bike shop told me that carbon saddles can only be mounted using clamps on the saddle. Is this true? Do I need to buy a different seat post?
If the top-bottom clamp is compatible, why are the rails so close together? Will it 'flex' into place when tightened? I don't have any experience with carbon and don't want to end up breaking the rails.
Here are some pictures.
Seat Post (Dis-assembled)
Seatpost Clamps on Montague Saddle - Good Alignment
Clamp on Brooks C13 Saddle