Originally Posted by
RolandArthur
The worn tyre is from the rear, I would put in on the front now so you can change both tires at the same time when it is completely worn. If it is worn so badly that it gives you trouble with flats it might be better to bin it and get a new one.
I would strongly recommend NOT putting a worn tire on the front. Traction on the front is much more important than traction in the rear, and a front flat is much more dangerous than a flat in the rear. The best course of action would be a new tire for the front and the old one in back, but if you don't want to buy a new tire, but the older one in the back.