Building the Quadracycle

This project was started in 2006. The detailed machine work was done by my friend Mike Farnam. The machine shop we used was extra busy over that summer and I could only get use of the equipment and Mike's time between 'work' projects. It meant the project ran several months late and many things have had to wait till very close to the deadline for completion.

This was an amazing project and I learned so much during the construction. I've continued to make design changes and improvements and I add them here as I can.

Click on any of the images to see a larger image. The latest photos are at the bottom.

Here's Mike machining out the disc brake spacers and threading the spacer for the disc. Mike is amazing! He was able to take all my ideas and turn them in reality.
Threading the hub for the disc.
Welding the spacer onto the rear axle.
From there the spacer was turned on the lathe to get the disc to run true.
Making collars for the rear axle and steering shaft.
Moving on to the steering (shown with only 1 seat positioned).
The steering shaft will pass through the frame so it will meet with the steering tie rod and the correct height (photo of the bottom of the frame).
A bushing has been made for the steering shaft and support.
A plate is welded to the bottom of the steering mount. This will be bolted to the frame to allow
the steering system to be removed if needed.
The steering support, painted with primer and bolted to the frame.
These are the derailleur/gear brackets being machined out by the computer. First the holes are drilled..
And the cutter makes its first pass on the part.
The CNC machine is about to start the second pass that will completely cut out the piece.
One down, 3 to go.
All I'm really doing is feeding oil onto the part and blowing off the cuttings to keep the bit clear.
The magic is all from Mike who programmed the CNC machine.
A perfect fit!
The completed brackets
Here the frame is getting its first coat of paint. Yes, it's red, like my truck and trailer.

Here the derailleur/gear brackets are being welded to the frame. The brake brackets were next,
leaving just the forward steering bracket and a center control arm to weld.


A close-up of the steering rod, awaiting the completion of the steering wheel assembly.
Test fittings for several of the components.
The drivers-side drive-line has been installed. It works great! A couple minor adjustments and it will be ready to try! The lowest gear ratio is 3/4 crank of the pedals produces 1 turn of the wheel. That's a slightly lower ratio than the lowest gear on my road bike. Note: Low is good! I don't need it to go fast but I do need it easy to pedal.
A setback.. We found out you can't weld an aluminum tube to a steel rod. The end parts will need to be remade in aluminum.
A front-on view.
Here you can see the cables, rear drive system and the center control arm. The arm will be formed upwards to put in reach.
This is the coupler for the steering wheel. It still needs the threaded holes for the steering wheel bolts and to have the 2 column pin bolts threaded.
The steering wheel coupler idea was reused to make the steering rod coupler.
The long piece of bar was used to determine a good location to bolt the tie rod end. The remaining part of the rod will be cut off.
Finally, the steering wheel and the tie rod are installed. I added a smaller chainring to see how low of a gear it may need.
A few more small changes and it will be ready to test.
Another setback! We found that the metal we used to make the center control stick was mil-spec hardened aluminum. If you try to bend it that is what you get. The failed bend was done on a scrap piece.
So, Mike came up with the idea of making a bracket that would hold the completed stick at an angle.
Outside for the first time! Mike is giving the bike a short try. Many of the parts were not fully bolted on so it could only be ridden a short distance.
Here I've pulled most everything apart and worked on the painting to keep the steel from rusting. I still had a lot of work to do on the drive system to make sure the gearing was low enough and that the chains would stay on.
This photo was taken after reassembling the components and before the front crash bar was mounted. In the background you can see my 'beater' bike, which will also be going to the event.
Here's a closer shot of the driveline and the cable routings. Note the 'flame' grip on the handlebar.
This little stub was made to go onto the steering support shaft (seen in the background). It provides a mounting location for the cycle computer and a horn.
Here are some quick supports for the shade cloth. It was just a test to see if it would be enough shade - it wasn't.
Here are the headlights. They are little driving lights and draw about 3 amps of current, so I'll wire them in series where they'll draw about half that.
The speedo and the horn are mounted on the stub.
The Quad, with the shade cloth. A nice try, but it needs to cover over the sides more effectively. The advantage of using shade cloth is the wind can pass easily through it. The disadvantage is it doesn't fully block out the sun.


Finally, after a year, I'm back to building parts for the bike. Mike is taking a couple photos of me working on the lathe while making the seat positioning pin parts.

Gotta keep the piece lubricated to keep from burning or breaking the tool or part.
Here I'm drilling out the mounting holes for the seats. These get mounted to the CNC so the outside can be cut.
Here the SuperMax CNC is milling out the base plate. The cutouts will reduce the weight of the seat brackets.
There are 2 seat plates and 4 side plates to cut. We estimated it would take 4 hours just to cut the side plates. The seat plates took half a day total to make because of the prep time.
Since I wanted to cut out a bit more weight, a cutout was needed in the side plates too. Hmm, what could that symbol be??
Yep, it's The Man.
Using a 'roughing tool', the mill cut the outer perimeter of the bracket.
Here are all the completed plates.
These are the two locking pins.
At this stage, the plates have been tack welded together and the locking pin plate is welded on.
The 2 brackets. After fully welding up the brackets and getting some primer on them, I'm test fitting them here.
We added 7 degrees of forward rake to the front wheels try to cut down the tires scuffing in tight turns. Giving it a quick test, it looks like it helped, but perhaps not enough. At this point it will have to do.
One of the new brackets properly positioned on the bike. It fits great! The old seat holes have been welded closed.
New for 2008: This one of the mounts for the overhead structure. Last year I used PVC and aluminum bars to make the overhead structure. I also had to use ropes to keep it upright. With these mounts, I'll be able to use metal to build the overhead frame.
A shot of one of the rear mounts. They're still in primer here.
This is one of the rear mounts with the spacers and copper pipe in place. To see the finished product, check out the On-Playa page.
Here it's 2009 and these are the new hubs for the rear wheels. When I switched to the plastic wheels, I hoped that the splines in the hub were up to the task of causing the wheel to spin while pedaled. But with hard pedaling the spokes would tear out, leaving the wheel to spin. I was able to get around it well enough for 2008 but I knew I needed something better. The parts you see here are 2 inner and 2 outer parts of the hubs. From concept to completion, these took 7 months. I'm no longer able to make or get things made in the shop so this will be one of my last parts of the project done there.
Since the CAD drawings for the disc brakes were used as a starting point for the hubs, the new hubs were a perfect fit to the drive shaft. You'll find an image of the new part on the Concept page.
Here are the hubs with a wheel after being painted.
There was one slight problem. Somehow I missed seeing the the bolt holes were a bit too far out. I had to ream out the wheel where each bolt passed through.
An assembled wheel leaning against my truck. Here you can see the recessed bolts nad the three holes for the drive shaft pins.
And finally a shot of the wheel back on the quad. The hardware store was short a few bolts so I'll add them when I can.


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