Tuesday, February 22, 2011

Car vs Car

Bike contraption next to partial zero emission Subaru wagon

I built a bike car starting last fall, and finished it this January. Where I live, there are quiet, flat streets that lead to a market, a hardware store, bank, and more. An easy thing to bicycle just a few miles, (less than five) and obtain many of the things you need. When it comes to many bags of groceries or icy roads, however, even a dedicated cyclist might pause, thinking that a large load or the risk of falling down on ice is cause to fire up the gasoline engine in the car instead. Perhaps, but this contraption removes some of the need to worry about those things. Plus, it's fun.

Frame construct detail

Center point steering

There is something very pure about a bicycle with only two wheels, an elegant diamond frame, and just the body of a rider propelling themselves in an amazing way along pavement or dirt. The physical arrangement is efficient, balanced, and can be very powerful. In that arrangement the rider outweighs the machine and strength to weight is outstanding.
I think of a jockey and a thoroughbred, harmonious and as fast as the wind.

But with this project, the metaphor of a draft horse is more suitable. Slower, yes. Stronger and more able to carry a load, that was the idea. A strong and steady horse, harnessed to a working mechanical construct. The benefit of a triad of wheels showed its value the first time I glissaded down a snow covered hill. Stable and steady, a fearless way to get around in the winter. (Even with cyclocross experience, there are days when conditions are too hair-raising for two wheels.) There is an open-wheel racing feel to the ride, and being low to the ground amplifies the sensation of putting the miles beneath you--so it isn't necessarily sedate or boring.

I designed the machine myself. It was a process of distilling metrics from the combined need to have good weight distribution while allowing room for cargo (and possibly a future stoker in front), have good ground clearance, and perhaps a canopy for sun and rain at some point. With 30 years of bike mechanic experience I didn't lack for insight and know-how. Yet I was willing to let this be somewhat an experiment, not tied to what others have done. This didn't mean reinventing the wheel, as good foundations are meant to be built upon. But I didn't feel wedded to existing designs. An internal gear rear hub does most of what I need, with eight gears. The possibility to add a front derailleur or even a mid-drivetrain set of auxiliary cogs exists, but I favor simplicity over convoluted chain lines. Time will tell.


  1. This is a video of a snowy spring ride on the bike car. The camera couldn't take a wider view than from the pedals forward, but you'll get the idea.


  2. If you're up for it, here is another video from early spring. Kind of long around 5 minutes. The music helps the scene go by-- in the beginning as I was leaving a shop where I volunteer working on bikes to be donated, you will see me weaving in the driveway on the snow on purpose, testing the surface. The bike car held pretty well. After that, my head can be seen turning left a lot to check for traffic in the street. I've since put a mirror on board. At the end the lens goes foggy with accumulating snowflakes.