Just don't turn your back on him, he'll charge and I'll spill my manhattan.
Some people who ride bikes are "People Who Ride Bikes" you know? They wear their clip shoes into the office and don't take their helmet off until they are at their desk and they don't own pants long enough to get caught in a chain. I am not one of these people. I would like to have a couch made of bike seats and invite them over to judge me though.