My rear tire (D207) is balding in the center and there is a faint line in the center of it (it is the band, or whatever, it is called). How big of a concern is this? I am scheduled to get a new tire put on Tuesday (I'll be out of town Friday-Monday) and I want to ride around town tomorrow since it has been raining for the last week and tomorrow is supposed to be very nice weather wise. Is 50-75 miles a real concern if I can see this band? Forgive me if this is an absurd question - I have no experience with this.