Start with riding position
An upright city-bike position and a forward road position load the rider differently. Use the saddle maker's intended-use guidance and, when available, a sit-bone measurement as a starting point rather than a universal answer.
Confirm rail compatibility
Check the rail dimensions, shape, and material against the seatpost clamp. Some carbon or oversized rail systems require a specific clamp. The saddle must also provide enough usable rail range for the desired position.
Set position in small steps
Begin near level unless the manufacturer specifies otherwise. Make small, recorded changes to height, tilt, or fore-aft position, then test one change at a time. Large adjustments can create new pressure or control problems.
Know when to get help
Persistent numbness, sharp pain, or instability should not be ignored. Recheck setup and consult a qualified bicycle fitter, mechanic, or healthcare professional as appropriate.