I just thought, what if instead of desinging a d sized bearing yoyo, they made a small diameter c sized. Like they made a Center Trak, but the angled sides were vertical, and the outside diameter could be smaller. I know that the bearing seat would be a size limiter, but i’m just wondering how small the bearing could be, while keeping the width.
So like. A very deep and wide groove?
I like it 
Simulates a D bearing, but would be able to adapt to all C bearing yoyos.
I can see that!
That right there is a nice idea.
Now that i’ve given it more thought, I think that it might slip binds because the response pads are kinda far from the string.
Not an issue.
Make the bearing a tad bit slimmer. BAM