Review on Park Tool Bottom Bracket Wrench by James Small

This tool is the only one of its kind that I have been able to find. Park Tool is known for its excellent quality bike tools. Yes, they have a lifetime guarantee. My biggest complaint about this wrench is that the metal is very thin. It's like trying to apply a lot of torque to the edge of a thin piece of metal, a little thinner than a kitchen knife. If your situation is similar to mine where the chain nut is very tight, you will have trouble using this tool. I had to wrap a piece of leather around the wrench to be able to tighten it enough to loosen the nut. (I felt like I was going to cut my hand before the nut came loose.) When the nut finally came loose, I also noticed that the wrench's teeth were very slightly bent - nothing stopping me from trying the tool again to use, only very slight bending. This can be a problem if the tool is used regularly, for example in a professional bike shop. In this case, however, a lifetime guarantee can be claimed. I believe they may have made this tool thin enough to be more convenient for those who want to carry this tool with them while driving. A thin tool is lighter. This tool should fit all one-piece cranksets except kids bikes with 12.5" wheels. (They have smaller one-piece cranks.)