After the brazing of the frame the cycle was definitely interesting. But I felt that I had basically created the penny farthing https://en.wikipedia.org/wiki/Penny-farthing . And furthermore I could see why it is a relic of history, it is hard to ride. Specifically the steering + pedaling is just not as easy as a “regular” bicycle. Its not easier and its definitely not fun.
So I bought a caster wheel that you would find on an office chair and swapped that for the back wheel.
So simple. Well at first it didnt work because with 2 degrees of freedom, the rear end would just pivot to one side and stay there throwing you off the bike. But by adding a spring between the front wheel and the main frame of the bike the spring can absorb the pedal stroke.
The idea of the second degree of freedom in the rear wheel and the spring is that the dynamics of the cycle need some way of absorbing the lateral force of the pedal stroke without requiring the steering to constantly be fighting the pedals. As an example, the user pushes on the right pedal. Some component of the force is in the plane of the wheel and turns the crank propelling the vehicle forward. The other component is perpendicular to the plane of the front wheel and tries to turn the front wheel counter clockwise. With the caster wheel in the back coupled with the spring, when you push the pedals the rear section of the cycle will deflect towards the left on a right pedal stroke.
Well the office chair was a solid piece of plastic and made a racket. But by swapping it out for a pneumatic wheel the results were fun. There was work todo. At faster speeds there was instability. The frame had too much flex which could fight stability. But it was no longer a pain to ride, it was fun.
TODO: Improve on this ideacomments powered by Disqus