Originally Posted by Kontact

Unfortunately, cyclists largely do not sit on the "sit bones" - the ischial tuberosity. We sit on those when upright in a chair, but leaning forward on a bicycle we sit somewhere on the narrower ischium or ramus - the rocker shaped bones going from the tuberosities to the pubis.

Specialized has popularized sit bone measuring, and then matching that number to a saddle width. But bone numbers are indirect. The outer 1/2 - 1" of saddle doesn't do anything - it just completes the shape. So that width is variable in its significance to sitting area.


So while some saddle brands may have a formula for matching sit bones to saddle widths, the overall scheme is like measuring peoples ankles to sell them shoes that are measured at the outer width of the sole, rather than measuring feet and the last.


The only really good way of finding a saddle is to sit on them. I have customers with sit bone widths exceeding the total width of the saddle. But they aren't sitting on those bones, and the ones they are sitting on fit the saddle perfectly.