So, I just got an Edge Ultimatum. After playing with it for about 3 hours, I noticed that the yoyo just started to have a weird vibrating sensation when It was spinning on the bottom of the string. Confused, I looked at the string around the bearing and saw it starting to fray:
P.S. The Edge Ultimatum is a really really really good yoyo. Definitely recommend.
It can happen across a variety of yo-yos… you’ll need to buff the inside near the string with some tough denim fabric or similar.
The bearing seat?
That might work, but when I just throw a sleeper without the string rubbing against the side of the yoyo, it still makes the weird rubbing sensation. And on top of that, the string is fraying on the part where it doesn’t rub against the yoyo.
It won’t hurt anything to spend a couple of minutes running the bearing seat/response area against some denim. My YYF Cypher was also a string cutter (strings would look very similar to your picture). Rubbing it against my jeans resolved it. I think it is just an aggressive blast that causes it and the denim treatment tones it down just enough.
So I just threw on a different string and realized that the rubbing sensation is just the bearing and that the previous string was probably just a bad one. This could be a false alarm but I’ll keep y’all updated if the yoyo really is cutting string. 
