I know you adventures plug your tires. Why does the bike shop refuse to plug? I have 500 miles on a new set of Metzler ZX6's and found a nail in the rear center deep groove. It was an easy fix and holds air. Am I screwed? Do I have to buy a new tire? Is the plug used only to get you to the shop to buy a new tire? Help me out everyone is telling me that I am going to kill myself riding on a plugged tire.