I was cleaning up my bike after a good ride and I noticed a place in my sidewall. I have Michelin XCR X'trem tires. I got these tires because where I ride there are a lot of roots and rocks and they go pretty good over them. I think a root or rock jabbed my sidewall, no flat though! It didn't go through the tire. I'll try to post a pic. My question is if these tires have weak sidewalls or is this just something that would have happened to any tire. If it's the tires, what are some good tires with strong sidewalls?