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A monowheel rider in the 2011 Doo Dah Parade, Columbus, Ohio
Hemmings' Unicycle, or "Flying Yankee Velocipede", was a hand-powered monowheel patented in 1869 by Richard C. Hemmings.[1]
1931 Cislaghi Motoruota monowheel, modified by Giuseppe Goventosa

A monowheel, or uniwheel, is a one-wheeled single-track vehicle similar to a unicycle.

Hand-cranked[2] and pedal-powered monowheels were patented[3] and built in the late 19th century; most built in the 20th and 21st century have been motorized. Some modern builders refer to these vehicles as monocycles, though that term is also sometimes used to describe motorized unicycles.

The world speed record for a motorized monowheel is 98.464 km/h (61.18 mph).[4]


Similar to bicycles, monowheels are stable in the direction of travel, but have limited horizontal stability. This is in contrast to unicycles which are unstable in both directions.[5] Monowheels have also been found to have a lower speed required for stability when compared to unicycles.[6]

A monowheel remains upright due to gyroscopic effects, but its lack of stability makes it highly dependent on forward momentum and the balance of the rider,[7] who must maintain stability while steering. Over the history of the monowheel, various stability enhancements have been tried such as support struts (Green & Dyer, 1869), skids and propellers (D'Harlingue Propeller-Driven Monowheel, 1914), as well as gyroscopes, fins, and rudders (The McLean V8 Monowheel, 2003).[8] Many riders choose to control stability when at a stop by putting their feet on the ground, similar to bicycles and motorcycles.[9]

Variants and related vehicles[edit]

There have been many proposals for variants or uses, such as a horse-drawn monowheel[8] or a monowheel tank.[10]

An electric monowheel called Dynasphere was tested in 1932 in the United Kingdom.[11][12]

In 1971, an American inventor named Kerry McLean built his first monocycle (aka monowheel). In 2000, he built a larger version, the McLean Rocket Roadster powered by a Buick V-8 engine, which subsequently crashed in 2001 during the initial test run. McLean survived and proceeded to build over 25 different variations of his version of the monocycle, from pedal powered models, 5HP models, all the way up to V8 powered models.[13] In 2010, Nokia used two of McLean's monocycles in their commercials promoting the new Nokia SatNav smartphone.[14]

One variant called a RIOT wheel was presented at Burning Man in 2003. It involves the passengers sitting in front of the wheel and being balanced by a heavy counterweight inside the wheel. Rather than the typical ring drive, this vehicle is powered through a sprocket attached to the spokes.[15][16]

A company in the Netherlands began taking custom orders for a monocycle variant called the Wheelsurf in 2007.[17][18]

A related vehicle is the diwheel or the dicycle, in which the rider is suspended between or inside of a pair of large wheels placed side by side.[19][20] An example of this would be the character Axel from the Twisted Metal series of video games published by Sony.[21]

See also[edit]


  1. ^ US 92528, Hemmings, Richard C., "Improvement in velocipede", published 1869-07-13 
  2. ^ Goddard, J. T. (1869). The velocipede: its history, varieties, and practice. University of Princeton: Hurd and Houghton. pp. 76–78.
  3. ^ US 325548, Lose, John Otto, "One-wheeled vehicle", published 1885-09-01 
  4. ^ "Guinness World Record for bearded woman Harnaam Kaur". BBC News. 8 September 2016. Retrieved 8 September 2016.
  5. ^ Sharp, Archibald (1896). "Bicycles & Tricycles: An Elementary Treatise on Their Design and Construction, with Examples and Tables". University of Michigan. p. 184. Archived from the original on March 28, 2022. Retrieved March 28, 2022 – via Longmans, Green, and Co.
  6. ^ Bert, Charles W. (1990). "Dynamics and stability of unicycles and monocycles". Dynamics and Stability of Systems. 5 (1): 30–35. doi:10.1080/02681119008806081 – via Taylor & Francis Online.
  7. ^ George, Patrick E. (6 July 2010). "How Monowheels Work". How Stuff Works. Retrieved 28 March 2022.{{cite web}}: CS1 maint: url-status (link)
  8. ^ a b "Monowheels: The strange story of vehicles with insufficient wheels". The Self Side. Archived from the original on January 30, 2011. Retrieved March 29, 2022.
  9. ^ Cardini, S.B. (18 September 2006). "A history of the monocycle stability and control from inside the wheel". IEEE Control Systems Magazine. 26 (5): 22–26. doi:10.1109/MCS.2006.1700041. ISSN 1066-033X.
  10. ^ "In Search of the Perfect Sphere". Retrieved 2022-03-22.
  11. ^ "The Dynasphere: The Car of the Future that Never Made it to the Future". Weird Historian. 2018-05-10. Retrieved 2022-03-22.
  12. ^ Popular Science: May 1932, p. 63, at Google Books
  13. ^ "McLean's Monocycle Story". McLean Monocycle. Archived from the original on 25 March 2022. Retrieved 25 March 2022.
  14. ^ "Nokia Commercials". McLean Monocycle. Retrieved 25 March 2022.{{cite web}}: CS1 maint: url-status (link)
  15. ^ Lyall, Jake (2004). "The R.I.O.T. Wheel". Archived from the original on 23 March 2022. Retrieved 22 March 2022.
  16. ^ Haney, Mike (15 April 2004). "Reinventing the Wheel". Popular Science. Archived from the original on 23 March 2022. Retrieved 23 March 2022.
  17. ^ "Wheelsurf Shop". Archived from the original on 23 March 2022. Retrieved 23 March 2022.
  18. ^ The WheelSurf - The Gadget Show (YouTube Video). The Gadget Show. 20 Dec 2007.
  19. ^ "The Holson Two-wheeled Electric Vehicle". Western Electrician. 23 Feb 1901. p. 128. Retrieved 25 March 2022.
  20. ^ "Dicycles and Diwheels". The Self Site. 16 Jan 2020. Archived from the original on 24 February 2022. Retrieved 25 March 2022.
  21. ^ Girgenti, Jim (14 April 2011). "Pre-order Twisted Metal For 'Axel' Early Access". Gaming Bolt. Archived from the original on 25 March 2022. Retrieved 25 March 2022.

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