This Pedal Cycle Has 9 foot Wheels And Floats On Water

Categories: Mobility

When I ran across this clip, I couldn't help but share.  Call it a contraption, a vehicle, a bi-cycle of sorts, a pedal boat, a crawler, or whatever you will.  When people get creative, great things come about.  This was a part of a Baltimore kinetic sculpture race in 2005 (which I had never heard of mind you):


A Peon's Eye View of the 2005 Championship Race

I had known Dave Hershberger for 18 years, and this seemed just the sort of thing he'd do. Having attended four Kinetic Sculpture Races, it was only a matter of time before he built his own sculpture. Dave's creations of any sort tend to be wildly innovative, the result of disregarding proven knowledge others have acquired for the excitement of learning new lessons himself.

A typical Kinetic Sculpture starts with a 4-wheel chassis which isn't anything special to look at, but solves the engineering challenge of getting through the race in one piece.  The art challenge is mastered somewhat independently by an exciting shell of fiberglass, plastic, mylar, extruded foam, or whatnot, fastened onto the chassis.  Dave never considered this conventional design.Peon Badge

Dave responded to both challenges with one sculpture, unifying form and function. He started with the wheels.  In the tradition of "What Would Hobart1 Do?", one could surmise there is little point in having small wheels when one can have large wheels.  Dave's garage had a 9-foot high door, which settled that.  Since building 9-foot diameter wheels would be difficult, he settled upon the minimum quantity of them—two.  And once one has a design with two 9-foot wheels, everything else starts to fall into place. You can read his construction website for those details. To implement his design, he developed and employed welding, mechanics, plastics, physics, hydraulics, and buoyancy. From the beginning, Dave sensed that his design, although straightforward, might be a bit difficult to propel through the 42-mile race. Thus was christened the Unwheeldy.


To attend the 2004 race, we made the mistake of flying into the nearest major city—Sacramento—where we stood in line at Budget Rent-a-Car for an hour before they jacked up the rate on our confirmed reservation and told us to take it or leave it.  Then we drove north for 6 hours.  To attend the 2005 race, we did it right and took a puddle jumper straight into Humboldt County.  That flight takes you back in time to when air travel was magical.  You land at the airport, walk 50 feet across the tarmac into the terminal, and right there beside the baggage claim are the car rentals.  Standing behind the one other customer to form a minimal "line" prompts the woman behind the counter to say "You must be Mr. Jones—welcome to Alamo!  Sorry for the delay—I'll be with you as soon as I'm finished helping Mrs. Himmelfarb here."  Ten minutes later, we had our baggage, our car, and were on our way, a magnificent welcome to the North Coast.

Five of us constituted her team. Captain, Pilot, and Creator Dave Hershberger enlisted Copilot Matt Frost, Pit Crew Members Karen Wallace and Elena Eneva, and Peon Tom Jones (yours truly). Unwheeldy was assembled in Pasadena, California, and accompanied Dave and Matt on a trailer for its 635-mile journey northward.  Tom and Karen arrived by plane from Greenbelt, Maryland.  Finally, at 1am the night before the race, the entire team was united with its vehicle at the grand old home of our hosts, Ellin Beltz and Ken Mierzwa, in Ferndale. All seemed ready.


Ellin Beltz creates some of the Glory awarded for the 2005 race. These are the ACE awards, consisting of the word "ACE" hanging from a wheeled chicken (just to the right of the torch). Pilots, crew, officials, and dignitaries are issued glory reflecting their achievements or contributions, and some pilots' chests tinkle with ACE and other glory from past races. Kinetic virgins like us are those in the race with but a single chicken.

The crowd was thickening two hours before the noon klaxon that starts the race. Dave, Matt, and Elena unpackedUnwheeldy from her trailer and discovered that the shift cable attachment bolt for one of the rear derailleurs had failed.  Dave and Matt called me to report the peril, then Matt dashed off to find a hardware store while Dave went to register.  Elena and I tended to the sculpture while Karen decorated our three crew bikes with ribbons, streamers, flowers, spinning pinwheels, and duct tape.  Dave obtained our race map, rules, t-shirts, and welded brass glory chickens (see right), but as other entries began their brake and safety checks in the square, our Team #125 was the only one without a sculpture.

Meanwhile in a parking lot off the square, Unwheeldy received a lot of attention. One 7-year-old boy asked "How do you true those spokes?", reflecting the astonishing mechanical proclivities of Humboldt County youth.  A water safety judge approached:

WATER SAFETY JUDGE: Floatation is.....?
TOM (presuming some sort of word game, since our means of flotation seemed obvious): Important?
ELENA: Good?
JUDGE: I mean, how does your sculpture float?
TOM: It's a boat!
JUDGE: Ahhhh...

Wheels 2
Wheel Diameter 9 feet
Wheel Circumference 28.3 feet
Spoke Count 120 per wheel
Spoke Material Hardened stainless steel wire, .09 inch
Spoke Length 51.625 inches
Hub flange diameter 8 inches
Drive Sprockets (x2) 112 teeth
18 inch diameter
19.5 pounds each
Drive gears 3 front, 7 rear = 21 total per side
(insufficient—a third transmission is needed!)
Hull material ~0.125 inch clear polycarbonate

At 11:30am, Matt returned with hardware, which he began installing.  At 11:45, Unwheeldy was complete, and Dave and Matt started pedaling her toward the square.  A crowd of spectators immediately formed around the sculpture, asking all sorts of questions, foremost among them "How does it float?"  To our surprise, even race veterans didn't recognize that the transparent plastic base of the sculpture would serve as a boat hull.

The Game Show Network interviews Unwieldy
The Game Show Network interviews Matt (wearing hat), and Dave (right side).

At 11:52am, race officials guided us to our official parking space.  Just as we finished backing in to prepare for the LeMans start, I realized we had not yet received our brake and safety inspection.  I mentioned this to one gentleman bearing a clipboard, whistle, and no small amount of glory around his neck, and he bellowed "You're late! 

Get to the starting line for the safety test!"  Blowing his whistle, he served as Moses, parting the sea of crews, officials, and spectators as Unwheeldy dashed around the square in a mad dash to be the final sculpture inspected at the announcer's stand.  As we sped around the town square, I suspect Unwheeldy could not have gotten much more attention had it been on fire.  As they glimpsed our huge spokes rolling past, some of the most famous faces in the Kinetic movement viewed Unwheeldy with open mouths.   Two engineering Judges approached, giving it the once-over: "We've never seen this before!"  "Very innovative design, reminiscent of the Killer Tomato2"  The safety team ordered Unwheeldy to accelerate down the street, and a judge stood in front and ordered a sudden stop in front of the reviewing stand to prove that Unwheeldy had brakes.  Dave clamped the brake levers, and Unwheeldy screeched to a rapid halt, with the crowd roaring as she rocked back and forth on her twin 9-foot wheels.  The pilots then evacuated the sculpture in a few seconds, another safety check.  Cliff, the KHUM radio announcer said over the loudspeaker "How does it float?" and I shouted back "It's a boat!".  At 11:58, with no time for the customary pilot sobriety check, Unwheeldy dashed around the square back to her assigned space. The klaxon about to start the race goes off every day precisely at noon according to an atomic clock. The World Championship Kinetic Sculpture Race always starts on time.

The chaotic laps around the plaza at the start as the whistle was blown. In addition to Unwheeldy, you can see the Frill Seekers' Dragon and the Cyclops on the far right. Hay bales protect spectators from errant sculptures. Unwheeldy was the only 2-wheel entry in 2005; Cyclops was the only 1-wheel entry. The pilot rode a unicycle the length of the course—even up the sand dunes—and carried a rubber raft for the water portion of the race.

In a LeMans Start, the vehicles start in one place, the racers across the street. Less than one minute after Unwheeldy was in her space, the whistle blew, and dozens of pilots dashed for their sculptures, including Dave and Matt. As Unwheeldy set forth on her maiden voyage around the town square, we pit crew followed along. As we were passed again and again, we realized we were one of the slowest sculptures on the square. After a couple of laps of sculptures careening madly around the square as thousands of spectators cheered, the timers threw open the starting line and sculptures poured from the square onto the street beyond. As we passed, a policeman reached frantically in his pocket, pulled out his camera, and photographed our twin wheels rolling by.

The racecourse heads out of Arcata toward the ocean along rural farm roads.  Every quarter mile or so, a cluster of tailgaters cheered on the racers.  We were passed by many a sculpture, and many of those passing took a photo of Unwheeldy, perhaps suspecting that we might not make it to the finish line.

The road from Eureka to the Pacific Ocean follows rural farm roads. (This road is actually the road to Ferndale from the last day, but they looked like this on the first day, too. It's not easy to ride a bike while taking photos with an SLR.)

As Unwheeldy approached the turnoff for the beach, our position among the racers was approximately last.  I had been racing ahead on my bike and moving traffic cones out of the way, for Unwheeldy was also the widest sculpture in the race.  (Dave had found in the Race Rules that the maximum allowed width was 8 feet, and had designed her to be 7 feet, 11 3/4 inches.)  At this point, I decided to follow a bit of strategy—I broke from the crew and dashed off at high speed to reconnoiter Dead Man's Drop.

So I surged ahead on my bicycle.  My bicycles at home are sized for my 74-inch height.  At the KSR, my borrowed bike was built for someone somewhat shorter; riding it reminded me why they make bikes in different sizes.  After I had bolted about 3 miles ahead of Unwheeldy, I realized I had left all my water with them.  It would be a long way back, and I thought "What would Hobart do?" and decided to persevere, parched.

A few miles later, I left pavement near Dead Man's Drop, and was exhausted.  We had been up late the previous night reunioning.  My mountain bike was no match for the trail's loose sand, so I abandoned it in the bushes.  I remembered that water would be vended at Dead Man's Drop, so I ran along the trail, until I was so exhausted and dehydrated I had to stop to rest to avoid passing out, even though resting meant I'd get more dehydrated in the meantime.  That's when the cloud of mosquitoes that had been trailing me caught up.

East of Dead Man's Drop is the site of the second-worst mosquito infestation I have ever seen.  This was clearly the least desirable spot in Humboldt county in which to pass out—before regaining consciousness I would be transformed through a series of miniscule blood donations into Tom the Human Welt.  So I persevered yet further.  Several minutes later, I came out of the bushes at the base of the great hill that is Dead Man's Drop.  Knowing that there were volunteers selling water at the top for $2 a bottle, I redoubled my efforts up the steep slope, resolving to purchase as much water as I could possibly need, and never to run out of water ever again.  About a third of the way up the hill, through the haze of heat exhaustion, a woman called to me by name, probably repeatedly.  I turned toward the voice and recognized a charming woman I had met at a Gone with the Wind party in Baltimore's Little Italy two weeks earlier, where I had been wearing a southern gentleman white linen suit, and she an astonishingly broad hoop skirt.  After brief conversation, and introduction to her parents, I staggered to the summit.


The scenery along the Pacific was beautiful as the waves crashed ashore. At this point, Dave and Matt had ridden Unwheeldy further than they had ever done before—they had been so busy building the sculpture that there wasn't time for training rides.

I bought two 24-ounce water bottles, drank them both within 3 minutes, and started to feel better. I arrived to see the lead sculpture go down the drop.

At the starting line, many pilots are obsessive about the cleanliness of their sculptures.  They'll wipe off a bit of dirt, and worry about scratches.  But by the time they get to Dead Man's Drop, that attitude has given way to fatigue.  The sculptures are sheathed in grime and sand, and the racers are sheathed in sweat and sand and no longer care.

After reporting on the situation via cellphone to the rest of the team, I hiked through the dunes to the beach to join them. On a desolate section of narrow trail, I happened to witness the most significant pilot illness of the 2005 race—a pilot got sick behind some bushes. (A medic arrived within a few minutes, and the pilot was brought to the hospital where he recovered.)

Once out on the Pacific beach, I ran north along the coast to meet the gang. 

Things were going reasonably well along the beach.  Dave and Matt heaved the sculpture along while Karen and Elena provided encouraging words. Finally, we reached the point at which the course left the ocean and headed inland, following a trail up and among the dunes, our first "Legal Push" area. Karen and Elena heaved and flailed to assist the massive mechanism's progress up the steep bit. Our goal at this point was to ACE the race, which means following a considerable number of rules that make the race significantly more challenging. Among them:

  • Your Sculpture must be ridden by all of its pilots at all times over the entire course. Therefore, at no time can your Sculpture be pushed, pulled, winched, or otherwise propelled along the course by pilots or Pit Crew or both, except in designated "Legal Push" areas. Your Sculpture may be moved sideways, or backwards either by pilots or Pit Crew, or both to gain supposedly better condition, but the Sculpture cannot be moved from the course.3

Liberally interpreted, we had been informed, this means that Pit Crew are allowed to "lean" against the sculpture to prevent it from sliding backwards, but that the sculpture cannot move forward except fully under its own power. Further, since I was a "peon" and not "pit crew", I was not allowed to push it even in the Legal Push zones. (The number of official pit crew cannot exceed the number of pilots; additional individuals are designated as peons.)

However, Peons are not prevented from smoothing the track, so I scurried immediately ahead, removing bits of driftwood and assorted debris.  It was obvious that ours was the widest sculpture through the dunes, for only the center of the path had already been thusly smoothed.

An interesting shortcoming of Unwheeldy became evident on the narrow trail. In his extraordinarily simple and elegant design, Dave had configured the sculpture so that the left pilot powered the left wheel, and the right pilot powered the right wheel. This "differential drive" avoided the need for a steering wheel—a turn to the right was accomplished by having the pilot on the left pedal faster than the pilot on the right. This design also allowed extremely sharp turns if one side of the sculpture braked while the other pilot pedaled. However, the tragic flaw in this design is that no human is effective at pedaling precisely as fast as another. Even in the flattest terrain, the merest bit of over-enthusiasm or under-enthusiasm by either pilot would cause the sculpture to turn toward one side or the other. In the dunes, this meant veering off the trail course, inevitably crashing into unsuspecting shrubbery. Driving straight has never been so great a challenge.

Unwheeldy's 2-wheel design also gave it an unusual method of surmounting obstacles. When the wheels came to a wide bump, they would stop rolling forward. The carriage holding the pilots, however, would ratchet progressively forward and upward, until enough gravitational potential energy had accumulated to cause the entire contraption to lurch forward over the obstacle, at which point the carriage and pilots would swing back down as the wheels rotated. The dunes were the first lumpy terrain we encountered along the course, and there was a great deal of lurching and swinging. When not lurching or swinging, there was a great deal of leaning to avoid losing ground.

Momentarily stuck on a sandy trail
Sometimes, a small obstacle would cause Unwheeldy to make a dramatic turn off the trail. Note that the wheels are not as perfectly round as in the preceding photos.

As we made our way through the dunes, occasionally giving way so that one of the few sculptures still behind could pass, Elena and I came to the realization that we were in jeopardy of violating another ACE rule:


  • Aly's Very, Very Late Law The Finish Line will close at 6:32 pm.... If you arrive at the Finish Line after the closing time, you will...lose your ACE status.3

The finish line that first day lay on the other side of the dunes, beyond Dead Man's Drop, over the Samoa Bridge, at the Eureka town square. Pragmatically, there was no way we would make it in time; progress was simply too exhausting.

But an even bigger problem presented itself. As we climbed hill after hill, with the ratcheting-lurching-swinging motion, Dave noticed that his chain was coming loose. A closer investigation revealed that the frame was bending. Before building any of his design, Dave had conducted a detailed strength analysis of every structural member.  In places where the structure needed to bear more weight, he reconfigured the design or made the metal thicker.  However, after he began putting the sculpture together, he realized it would be nice if pilots shorter than six feet tall could drive it.  So he decided to make the pedal position adjustable.  Unfortunately, in adding that adjustability, he introduced an Achilles heel that hadn't been part of the original analysis.  During periods when the sculpture ratcheted upward to accumulate potential energy to surmount an obstacle, all that energy was channeled directly through a steel tube supporting the pedals that was merely 1.5 inches in diameter. And that tube was bending.

We stopped and considered our situation. It was agonizingly obvious that we would not be able to make it up the remaining dunes without the tube bending to the point that Unwheeldy would be unridable. Further, there was no spare tube among our spare parts.  We needed a replacement, welded in place. We had no welding equipment, nor even the tools to take apart the bent frame. The future was cloudy.

While we sat there contemplating doom, we heard a motor over the horizon. A Unimog—a giant elevated motorized dune buggy contraption that laughs at the feebleness of other SUVs—drove down the trail and stopped just in front of us. Out sprang its driver, festooned with Glory, and an official badge reading "Aly Krause, ACE JUDGE". In the blink of a moment, he assessed the situation, and said "You guys are in a pickle. I'm afraid if you can't proceed I'm going to have to disqualify your ACE." We grunted miserable agreement. He continued, "Guys, this is an incredible work of engineering, and we all want to see it cross the finish line. It looks like if you just bend the bar back straight, add a triangular supporthere, and add another support here, you'll be back on the road. I've got a welding shop in Eureka—if you want to bring it there tonight, we'll straighten you out." It turned out Aly is one of the most experienced racers on the course, and his sculptures have won more Speed awards than anyone else's.  The speed rule quoted above is named after him.  We later learned that one of the spectators who saw us break down was one of the HAMMs—amateur radio operators who support the race operation by keeping an eye on the racers. They keep an extra-close eye on any sculpture signed up to ACE the course, and referred to us as "Big Wheels".  Seeing us in trouble, they summoned an ACE judge to witness our breakdown and cross us off the ACE list.  But, in the fabulous Kinetic spirit, they sent a judge who could offer the supplies, equipment, and expertise to repair the damage.

Relieved of the pressure to ACE, the rule against pushing the sculpture no longer applied.  Working together, we heaved Unwheeldy to the top of Dead Man's Drop.

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