Unless I am missing something I am not sure how you could be wearing the edges of the front tire on a dropped and stretched bike. The edges of the tire have to make contact with the ground to wear out and I don't know how you would even get the edges in contact with a stretched and lowered bike. Seems like you would drag a peg first... Most people have the opposite problem, they wear out the middle of the tire and have to get new ones when they still have tons of good rubber on the edges.