Have you marked your clutches to see where the belt is travelling in each sheave? Looks like it may be bottoming out in the secondary, but the sled definitly shouldnt feel normal if thats happening.
You could take a paint pen and paint the the shaft on the fixed side of the primary. This will give you a little more wear time than a sharpie. And with a sharpie mark both the primary and secondary clutches and see where the belt is traveling to on a track stand and in theory tell you if the belt is bottoming out on the secondary or if the wear is coming from the primary as the motor torques.
Works in my head anyways but I've never tried it myself.
Also just thinking about having the motor out...technically there is an xyz spec for the clutches but its supposed to be non adjustable so when it went back in you wouldn't have had to worry about aligning it...just bolt it back in and away you go. If you have the shop manual check the xyz on the clutches all the same, maybe it is out a bit.
Has the sled ever had a hard impact that could have tweaked the front of the sled ever so slightly?