Sprocket
After working on a few projects exploring the structural integrity of Baltic birch ply, combined with variuos methods of “plate” construction, it seemed a bicycle was a perfect candidate to put some of these methods to test. The goal was not to create a bike that could compare to modern alloy frames but simply to create an efficient structure while satisfying the demanding functional requirements inherent in this machine.
The two main areas where some level of invention would be required are the headset location and the rear stays where the rear tire is mounted.
Rear “Stays” support
There is a tremendous load applied to the rear seat and chain stays of a bicycle, especially while pedaling. To counter these forces the design incorporated cargo baskets on either side that serve to structurally “buttress” the rear wheel mount.
Headset design
As you can imagine, the headset applies a great deal of load to the location where it is mounted. It was important to maintain a light appearance while distributing the load as widely as possible. The devised solution allows for each of the six brackets housing the headset to share the load to its neighboring brackets. The result was satisfactory though the pins were added later to reinforce the attachment to the main frame portion of the bike.
Chain Stays and tensioner
It became apparent once the rear tire and tensioning mechanism where installed, additional support would be required to resist chain tension from buckling the rear stays. Threaded brass rods served this function well while adding an attractive brass finish complemented in the rear hub and headset mount.