bikerumor monday mystery bike part picture

Photo from the collection of Rustybicycle. If you think you know what this is, post your answer in ‘comments’ – the answer will be posted there on Tuesday!

To send in your own Mystery Pic to be considered for the Monday feature, click here and attach your photo with all pertinent information.



  1. Looks like a linkage from a Schwinn Air-dyne that helps connect the crank-arms to the moving handlebars. Probably one of the last hold-outs for cotter pin usage.

  2. It looks like it could be an extender, but it it would run perpendicular to the crankset. You’d have a 90 degree bend in your crankarm, I think. that might look cool.

What do you think?