Q:  What is the dumbest thing you have seen someone do to a bike that you had to repair? A:  I'd have to say the worst thing I've seen is WD-40 being used as a chain lube, although I don't blame people for it as it's been a popular misconception for so long. The second worst thing I've seen is stripped out bolts from people using the wrong tools. http://www.bikehacks.com/bikehacks/2011/.....tutor.html