I have a B17 Imperial that is too narrow for me (on my Mezzo folder), a B68 that is the perfect width and very comfortable, except that the back of my legs at the joint with the hip socket hit the edge of the saddle while peddling (on downstroke). The B72 (sprung) has essentially the same overall width as the B68 (209 mm vs. 205 mm), but doesn't appear to taper or widen as quickly from the saddle nose as the B68. In other words, the B72 is narrow from the saddle nose for a longer distance towards the back of the saddle. Because of this I think my leg hitting issue could be resolved with the B72.
Can any of you confirm this or have experience with this issue? Sheldon Brown's website (for the B72 description) says "for general riding comfort go with the fully sprung B66." I wonder if the B66 has the same taper as the B72, or is it more like the B68? I would like the B68 if it tapered the same and because it comes in black and works with my micro-adjust set post (without the sandwich).
Wasn't sure where best to post this - here, commuting, touring, etc??