July 28, 2010 12:37 PM PDT
I use to work in a tire shop and what you are describing sounds like a tire separation ...where the inner layer detaches from the tire and the air pressure bubbles out the tire ether on the sidewall or the tred. doesnt take much of a separation to cause this problem and its hard to detect till your riding it. sound like the shop you took it to is trying to milk you. try a used or new tire if handy to test for this problem. good luck
