I have a Pro on my bike and a digital calliper. Maybe I can help?

What do you mean by a "true 148" saddle?

What I mean is that since there is a taper on the sides, is there actually 148mm of space for your sit bones on the saddle?

Check out https://www.stevehoggbikefitting.com/...1/09/all-about-smps/

The saddle has a flat central part, and as you have noted, tapers off at the lateral edges. The rear, rounded area is 148 mm wide, but not flat (pic 1). Approximately where I think most of my contact with the saddle is, the flat part is about 73 mm wide (pic 2) and the actual saddle is 77 mm wide (pic 3).



That's about here on the saddle (pic 4). You can also see there is a definite scoop which you sit in. I occasionally push a bit further back whilst climbing, and the saddle is 75 mm (pic 5) there.

Thanks for the detailed info! Seems to be a lot narrower than I suspected!

Yeah, it seems very narrow. I've tried a number of saddles and I'd say I have a reasonably wide pelvis (I'm 6'5"). The pelvis seems to lock onto the saddle more than any other I've tried. It felt "right" from the outset, so I wouldn't be put off by it. I think SMP have quite a good testing program where you can borrow one from a local dealer.

Here's my road bike so you can see my saddle to bars drop and hopefully it'll help the decision process.

All the best,
JB

Look at the SMP Avant if you want width.

I have -- worried that the nose is way too wide however and will cause chafiing.