Adjusting the saddle angle on a single bolt saddle clamp without grooves I am about to buy a new seat post on the Internet. Looking at the pictures, the saddle clamp has a single bolt, but I can not understand how it could adjust the saddle angle. ![enter image description here]( ![enter image description here]( The seat post I currently use has these grooves on the saddle clamp, so I can adjust the saddle angle quite easily. ![enter image description here]( What are the differences between these two types?

From memory, the top seatpost has a slot on one side where the bolt passes through, which is not visible in the image. This allows a range of movement. The underside of the bolt head is either not flat, or it is in a cone-washer that conforms to a conically-sided hole.

However with two smooth sides pressing together, the only thing stopping the clamp from sliding is pressure.

Your second seatpost is "superior", though a two-bolt design leaves them both behind for strength and adjustability.