- The Muc-Off Chain Doc eliminates grime from bicycle chains with minimal effort. This life-saving chain cleaning machine works by clipping over the chain and combining heavy-duty rotating brushes with the awesome power of our Muc-Off Bio Chain Cleaner. It will bring your chain back to life in seconds... 19 to be exact. The Chain Doc comes complete with a can of Muc-Off Bio Chain Cleaner, making it ready for cleaning straight from the box.