It's a bit of an off-the-wall idea, but has anyone considered skimming the outside diameter of an AT pulley to reduce backlash?

If you look at this diagram on the Brecko website, it is clear that the belt tooth peak does not contact the bottom of the pulley profile with standard T pulleys and the belly valley has a more substantial clearance on AT pulleys.This is in stark contrast to the reduced and zero backlash pulleys.

So, for a rough but hopefully effective solution, reduce the peak of the pulley profile so that the belt bottoms out fully and there is more belt valley clearance.

In the AT design specs, the belt teeth are supposed to bottom out. I presume they don't in a standard pulley due to either lifetime concerns or manufacturing tolerances or both.

https://www.brecoflex.com/blog/timin...0AT%20pitches.

at tooth form.pdf