13 May – I've had a couple of brainstorms on easy ways to put the drive train together so that will be the next item. I've actually already assembled the crank into a separate model section as shown here. All I have to do is cut holes in the frame of the mockup and I can pedal this thing away. However, I'm going to put the whole drivetrain together in a test box first before I do. Once the drivetrain is on and working I'll start building the final prototype. The intermediate shafts will have freewheels (BMX SS on one side and multi-speed on the other. More details to follow as I get the test box finished. The box now has 2 left-side crank arms. If anyone has some square-taper unicycle cranks they'd let go cheap please let me know (~165mm).

I replaced the steering linkage rod after the first one broke and added brakes (although they barely work). Things have been holding together for the short coasting testrides I've taken. I had a minor problem with the rear BMX freewheel coming loose and binding up the rear wheel. It was a while before I realized what it was, tightening the freewheel solved it.

15 April – First coasting ride. This is really the furthest I've ever gotten building a bike entirely by myself (although the craftmanship shows it's mine). Still, it's a good feeling after dreaming about it for 30 years.
Haven't thought of what else to say about this picture yet. I guess the smile says it all. Next project is to get brakes and a drivetrain installed (and maybe upgrade the wood parts from pine to oak.) Cost to build so far has been less than $20, mainly for the 4x4” fencepost that forms the frame and the hardware store bolts. It turns out the mockup is sturdy enough to take for short testrides. I took it around the block tonite - no lites, no brakes, no problems (yet). I've put a headtube from a kids' 20-inch stingray on the front using u-bolts. The steering post is in the headset sawed off a mountain bike. The seatback is a skateboard deck that a young friend of mine had just broken a wheel off that day. Seatback supports are old skipoles from a garage sale. (I'm looking for graphite ones to use for the steering rod). Rear triangle is made from Al angle and plate. Endplugs are pine 2x just held in with screws and bolts.

1 April 2007 - Transmission prototype – using a 24” unicycle fork and 2 modified freewheels. There are 3 chains. The front one goes from the crank (unicycle hub) to a cog on the backside of the first freewheel. The second chain does all the shifting by moving in parallel lines on both freewheels at the same time (like the belts on drill le-press pulleys). From the backside of the second freewheel a cog drives a single-speed cog on the back wheel. The chains can all be fully enclosed by this method. Number of speeds is limited to the number of gears on the intermediate freewheels, but there's a trick that can double the number of speeds.

1 April 2007 – Mockup. The name comes from the fact that the frame box is a 4x4 PVC fencepost from Lowe's hardware. The front fork and headtube is sawed off a kids' 20” bike. The rear triangle is aluminum angle. The seat is a skateboard deck, supported by sawed-off ski poles. I may get more elegant for the prototype, but this fencepost is pretty sturdy and the mockup may be rideable.

Nov. 2006: Here's the CAD sketch that got the project started. At this point I had decided to cluster all of the transmission elements together in the front of the box, making shifting and maintenance easier. This was as far as I got until the fateful day in March when I discovered that you could buy 4x4” hollow PVC fencepost.

May 2006: I started out in late 2006 butchering .jpg files with MS Paint. This is a modification to the design that I want to try out eventually. The Z-frame permits me to retain the enclosed drive and have a sliding seat track that is lower and has constant seat height no matter where the rider adjusts the seat position. The frame bends are in the locations of the intermediate drive so that the chain doesn't have to make any bends.