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Dr. Richard Klein is our resident bike authority, and so a fairly large section is presented for your browsing pleasure on the general topic of "Bicycle Science." Enjoy!

Why is this “bicycle science” on a web site and not in a book or scholarly journal?

The Wright Brothers were scientists by every conceivable measure or standard, and yet the nature of their quest demanded that some degree of proprietary standard be maintained. In a similar manner we can and will show general pictures and discuss scientific matters publicly, but we reserve the right to not share details concerning hardware specifics, teaching protocol techniques, teaching methods as related to various types of disabilities, individual case histories, and the like. This is done not so much as to deny these results to the public, but to safeguard the integrity of the process by which the Lose The Training Wheels™ program expands.
A reason for the inclusion of this material on “bicycle science” on this web site and to the lay public is to comply with some longstanding requests. Dr. Richard Klein, while at the University of Illinois became involved in an extensive and extended study of the bicycle. This study has been on-going for over two decades, specifically since the spring of 1983. At numerous times, lay as well as professional people have requested access to some of the findings. Normally, if one studies an issue in the scientific world, the customary mode is to publish the findings in peer reviewed and scholarly publications. Dr. Richard Klein has refrained from publishing previously. The reasons are many, but we will cite several:
  1. The work involved the work of literally hundreds of undergraduate students, almost one thousand, and over a span of two decades. Most students involved wrote project and semester length reports. It would be unprofessional to publish those findings without crediting the sources, as well as authenticating the accuracy and validity of the results. In reality, it isn’t beyond the realm of possibility that some student along the way “dry-lab’ed” a report, that is, wrote a paper based on less than perfect attention to scientific rigor.
  2. If a comprehensive compilation of findings would be put together, it would fall on Dr. Klein to personally take the time to duplicate, authenticate, and replicate each finding. In short, this would involve considerable time. In our case, creation of an adapted bicycling program for children with disabilities assumed a higher priority. Life gets to be quite pleasurable when one can devise and implement a scheme to permit a developmentally challenged child to ride a bike for the first time in his/her entire lifetime, to enjoy exhilaration – and end up smiling.
  3. If a scholarly publication were to be prepared and submitted, the rules and dictates of science demand that experimental conclusions and findings be replicable, and hence we would be under a burden to share what we regard as proprietary.
  4. Dr. Klein has recently collaborated with colleagues Dr. Karl Astrom and Dr. Anders Lennartsson in Sweden, and together (Astrom, Klein, Lennartsson, 2005) have authored an extensive paper for publication in the IEEE Control Systems Magazine. This publication, to appear in the August 2005 issue, will allow the mathematical and system theoretic principles regarding bicycles as avowed to be subject to scholarly peer review, as well as published and thus to be made accessible to a worldwide audience. In this web site we are focusing on a lay audience explanation, along with emphasis on experimental findings as opposed to mathematical derivations suitable for the scientific elite.
With all that said, in this section we will delve into the matter of why a bike stays upright, as well as a number of variations of the same question. We agree that stationary bikes, when not held upright by a kickstand or other support, will fall over. When a bike is moving forward, the situation becomes far more interesting.
The Experts and Seers
The first dilemma that we presently face is that a number of authorities heretofore have looked at the bicycle and have rendered judgments. We point out that critical experiments were commonly not considered as necessary in order to arrive at conclusions, as it appeared to the seers that the conclusions are blatantly obvious. Herein we will argue that the bicycle and its solutions are hardly “obvious,” but rather complex and even counter-intuitive.
Notable among the seers is Macaulay (1988) in his widely acclaimed international best seller children’s book on science. Macaulay declares that precession is “required” in operating a bicycle. Macaulay is actually vague in his discussion of how the bicycle works, but our interpretation based on his illustrations as well as context, is that Macaulay is saying that precession is the essence when it comes to explaining the secrets of a bicycle.
The very title to Macaulay’s book in first edition was “The Way Things Work.” In his revised edition (1998), the title became “The New Way Things Work.” Bicycles are discussed in both editions in the context of gyroscopes and precession. Nothing is mentioned or provided by Macaulay to even hint that any other mechanism or explanation might be relevant. The very focus of Macaulay’s presentation and treatment, in our opinion, leads the reader to believe that the gyroscopic argument is the primary mechanism responsible for keeping a bike upright. We feel that Macaulay’s explanations and presentations regarding “the way a bicycle works,” to paraphrase his title, are without experimental or empirical evidence, are thereby unscientific, and are flawed.

Yet another "expert and seer" is a web site called "The Straight Dope."

Dear Straight Dope:
Why is balancing on an unmoving bicycle so much harder than balancing on a moving bicycle? --Benjamin
SDSTAFF Karen Lingel replies:
Because modern bicycles are equipped with a pair of gyroscopic stabilization devices that require the motion of the bike in order to operate. These devices are known as "wheels."

Ms. Karen Lingel (on The Straight Dope web site) then goes into a discussion of the right-hand-rule and how the gyroscopic action of the two "stabilization devices" causes the bicycle to stay upright, as well as to execute turns to the right and the left when the rider executes appropriate leans thus bringing the right-hand-rule into action.

We assert that Ms. Lingel has never conducted an experiment such as trying to ride the bicycle pictured below. We have. Please understand that this bicycle below with two upper counter-rotating wheels creates (when in motion) equal and opposite precession torques on both front and rear portions, and thus functions as if the gyroscopic contribution is zero. This "zero-gyroscopic" bicycle is not only rideable, it is easily rideable. Literally hundreds of persons have ridden this and similar bikes, ranging in age from grade-school children to seniors.

Please continue on to search the adjoining tabs in this "Bicycle Science" section of our web site for more discussion. As time permits we will be posting video footage of various experimental bikes being ridden.

World's First Zero Gyroscopic Bicycle. This bike was built by a team of students at the University of Illinois in Urbana-Champaign, circa 1980's. Later we built a version using a twenty inch tire diameter, as this bike was pretty awkward to load up and take on the road as we did bicycle science demonstrations. Not only is this bike rideable, it turned out to be easily rideable!

We must comment that Dr. David Jones in England performed somewhat similar experiments in the late 1960's, however Jones' experiments did not cancel both front and rear gyroscopic actions. Jones used only a single wheel mounted on the front fork that he could spin in the reverse direction by hand. In our UIUC designs, the upper counter-rotating wheels are in contact with the lower wheels and by friction, as well as having neglible tractive loading, maintain essentially equal but opposite rotational velocities. For the sake of the skeptics who still doubt, we have also conducted experiments where we have added extra mass to the upper tires thus giving our UIUC experimental bikes a negative gyroscopic action.

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