So I am selling my Pro to a buddy and I was going over it today and listing all the stuff I had added to the sled and looking for any problems I could fix before I sold it to him. I checked the QD belt for wear/damage and noticed what looked like some wear on the outside of the belt. On close examination it looks like the belt rubbed on something and had worn and frayed on the outside. On close examination it looks like the belt rubbed on something like a wire or something else plastic and it's just stuck to the outside of the belt. There is nothing close to the belt that could have rubbed and all the battery wires are ty wrapped away from the quick drive belt. Any ideas? Also, is that a crack in the brake disc? Is that a warranty item?