Most people who ride bikes will at some stage have wondered if a linear motion of the legs, as in walking, would be more natural than pedalling. Such reflections prompted my own experiments described here. As so often happens, one later discovers that it has all been discovered by others long before...
This bike can be adjusted at three points:
Front wheel: 32-451
Rear wheel: 26 x 1,25 inch
The seat is fixed, and the arms pull on a column that is also used for steering and which is linked by a cable going forwards and over a pulley to the feet. You push with your feet and at the same time pull with your arms. The result is a smooth flowing motion that ends with a relaxation of the body before the legs are pulled in for the next stroke.
Other models of the Thys Rowbike are also available, including a back-to-back tandem. In the early 90's Derk Thijs won the 570km Paris-Amsterdam race. He more recently set a record time of 13.53 hours in the Amsterdam-Paris run with a rowbike.
Interestingly, the most recent Thys Rowbike uses a spiral pulley drive train that was invented more than 100 years ago (see US patent 606854 granted to John Bergstrom in 1898). The cable unwinds off the pulley as the stroke completes, which is very efficient ergonomically. It also allows an infinitely variable-ratio transmission.
Nearly all rowbikes now have a bowsprit between the legs, and that seems the most efficient design.
Rowbikes seen at VeloVision 2008, Amsterdam:
(Photographer: Bas Dekker)
The pictures give a good idea of the low frontal area achieved by the rowbike. These state-of-the-art machines put to shame my own humble effort!