Unicycle

A unicycle is a one-wheeled human-powered vehicle. Unicycles are similar to, but less complex than, bicycles.

Construction

Unicycles are composed of a few key parts: the wheel (which includes the tire, tube, rim, spokes, hub and axle), the cranks, pedals, fork-style frame, seatpost, and saddle (the seat of the unicycle). The wheel is usually similar to a bicycle wheel with a special hub designed so the axle is a fixed part of the hub. This means the rotation of the cranks directly controls the rotation of the wheel (called direct drive). The frame sits on top of the axle bearings, while the cranks attach to the ends of the axle. The seatpost links the frame to the saddle. There are many different types of unicycles, which can include (but are not limited to): freestyle unicycles, trial unicycles, MUnis, giraffes, and long distance unicycles, which all have special components unique to that type of unicycle.

History

The unicycle's history began with the invention of the bicycle. Comte De Sivrac first developed bicycles during the late 18th century. His device, called a celerifere, was a wooden horse that had two wheels joined by a wooden beam. Germany's Baron von Drais improved the design by adding a steering mechanism, introducing his Draisienne or "Hobby Horse" in 1818. Kirkpatrick Macmillan, a Scottish blacksmith, added cranks and pedals to the front wheel in 1839, and called it the Velocipede. The first mass-produced riding machine, the Michaux Velocipede, was designed in 1863. In 1866, James Starley developed the penny-farthing, a bicycle with a very large front wheel and a small rear wheel. One theory of the advent of the unicycle is based on the popularity of the penny-farthing during the late 19th century. Since its pedal cranks were connected directly to the front axle, the rear wheel would go up in the air and the rider would be moved slightly forward. This likely prompted riders to see how long they could ride with the back wheel in the air, and thus the unicycle was born. Evidence for this theory of development can reportedly be found in pictures from the late 19th century showing unicycles with large wheels.^[1] Over the years, unicycle enthusiasts have inspired manufacturers to create new designs, such as seatless ("ultimate wheel") and tall ("giraffe") unicycles. During the late 1980s some extreme sportsmen took an interest in the unicycle and off-road unicycling (MUni) was born.

Unicycle types

Freestyle unicycle 

Generally used for flatland skills and routines. Usually has a relatively high seatpost, a narrow saddle, a squared fork (used for one-footed tricks), and cotter-less cranks, as they do not need to withstand very much pressure. These unicycles are used similarly to flatland bicycles. Some examples of freestyle unicycles include Miyata, Nimbus, Schwinn, and Semcycle brands. Prices typically range from US$100 to $300. Wheel size is usually 20 inches, but smaller riders may use 16-inch unicycles. Some people prefer 24-inch wheels. Freestyle unicycles are stronger than most other types of unicycles.

Trials unicycle 

Designed for unicycle trials, trials unicycles are stronger than standard unicycles in order to withstand the stresses caused by jumping, dropping, and supporting the weight of the unicycle and rider on components such as the pedals and cranks. A recent development in trials unicycles is splined cranks and hubs, a feature that is very useful and somewhat expensive. Many trials unicycles also have wide, 19- or 20-inch knobby tires to absorb some of the impact on drops.

Offroad unicycles ("MUnis") 

"MUni" is an abbreviation for mountain unicycling. MUnis have many of the same components as trials unicycles, but have a few key differences. Usually, the tire diameters on mountain unicycles are either 24 or 26 inches, allowing the rider to more easily roll over obstacles such as roots and rocks. The seat is also thicker and more comfortable on MUnis to compensate for the rough terrain. Brakes are sometimes used for steep descents.

Touring unicycles 

Used for long distances, these unicycles are specially made to cover distances. They have a large wheel diameter, between 26 and 36 in., so more distance is covered in less pedal rotation. A 36" unicycle made by the Coker company started the big wheel trend. Some variations on the traditional touring unicycle include the Schlumpf "GUni" (geared unicycle), which uses a two-speed internal fixed-geared hub. Larger direct-drive wheels tend to have shorter cranks to allow for easier cadence and more speed. Geared wheels, with an effective diameter larger than the wheel itself, tend to use longer cranks for control, as the speed comes from the gear ratio, not the wheel itself.

Variations

A Unicycle Hub

• Giraffe unicycle: a tall unicycle, usually chain-driven (but includes multi-wheel unicycles).
• Geared unicycle ("GUni"): a unicycle whose wheel rotates faster than the pedal cadence. Used for distance riding and racing.
• Multi-wheeled unicycle: A unicycle with more than one wheel, stacked on top of each other so that only one touches the ground. The wheels are linked together by chains or direct contact with each other.
• Kangaroo unicycle: unicycle that has both the cranks facing in the same direction and the hub off-center. They are so named due to the rising and falling motion of the rider, supposedly resembling the jumping of a kangaroo.
• Ultimate wheel: a unicycle with no frame or seat, just a wheel and pedals.
• BC wheel : a wheel with pegs or metal plates connected to the axle for the rider to stand on. These wheels are for coasting and jumping. A purist form of unicycling. There are no cranks.
• Monocycle (or monowheel): a large wheel inside which the rider sits (as in a hamster wheel), either motorized or pedal-powered. It is not plagued by the normal unicycle balance problems because of the greater gyroscopic properties and lower center of mass.
• Eunicycle: a computer-controlled, motor-driven, self-balancing unicycle.
• Freewheeling unicycle: a unicycle in which the hub freewheels, allowing the rider to coast or move forward without pedalling, as a bike would. These unicycles almost always have brakes because they cannot stop the way traditional unicycles do. These unicycles also cannot go backwards.
• Other variations include tandem, recumbent, hydraulic giraffe, unibike, suicycle, and motorized unicycle.[1]

Theory

A unicycle is a form of inverted pendulum. It is also a nonholonomic system because its outcome is path-dependent. Balancing a robotic unicycle or a eunicycle forms an interesting problem in control theory. (See Segway.)

Speed

The pedals of a typical unicycle (e.g. not a giraffe) are connected directly to the wheel. This means that there are no gears to shift, as there would be on a bicycle. It also means that wheel size is a major factor in unicycle speeds:^[2]

Riding

Alex Toms of Sydney, Australia demonstrates Street unicycling (March, 2006).

Traditionally, unicycling has been connected with parades or the circus. This is because the unicycle requires a great degree of skill to ride, and many people who could ride them became entertainers. Recent developments in the strength and durability of bicycle (and consequently unicycle) parts have given rise to many riding styles such as trials unicycling and mountain unicycling. Unicycling has therefore developed from primarily an entertainment activity to a competitive sport and recreation.

Riding styles

Neighborhood

For basic unicycling, this is the place to be. Not too long ago, all mass-produced unicycles were in this category. Basic, cheap unicycles such as the Torker CX are used.

Freestyle unicycling

"Freestyle" means to do skills, stunts, or tricks. Not only is freestyle a well-known term in BMX bicycling, it is also the name for a competition event in unicycling.

Trials unicycling

Trials unicycling is specifically aimed at hopping and riding over obstacles. Because of the constant pounding a trials unicycle endures, it must have a very strong axle and crankset.

Street unicycling

Street unicycling (or simply "street", as it's known within the sport) is a style of unicycling where riders use combinations of objects found in urbanized settings, such as curbs, ledges, handrails, stairs as well as flat areas to perform a wide variety of tricks.

Off-road or mountain unicycling (MUni)

Unicycling on rough terrain has been the swiftest growing form of unicycling in recent years. Any place a mountain bike can go, a mountain unicycle can go as well — and sometimes more easily, due to the unicycle's greater maneuverability.

Touring or commuting

This style is meant for distance riding. With a 29-inch or 36-inch wheel cruising speeds of 10 to 15 mph can easily be reached. However, the smallest wheel diameter to fit within the "touring" category is 26 inches.

Extreme unicycling

Jess Riegel shows an example of grinding, a street unicycling skill

Recently, unicycling has gained popularity as a sport, and as a general means of transport. In the last 10 years, unicyclists have taken unicycles out of the traditional parade, gym, or circus setting and have created new forms of unicycling. These forms can be described broadly as "extreme unicycling":

Unicycle trials

Trials involves riding over obstacles of any sort, either in natural terrain or in an urban environment. The challenge relates to technical difficulty over short distances, and the objective is to use any riding techniques necessary to ride up, over, or down an obstacle without falling.

Mountain unicycling (Muni)

Combines cross-country and trials challenges, where the objective is to ride technically difficult terrain over some distance. Extreme sport videos and films typically show Muni as primarily descents of difficult terrain, but the term also includes difficult uphill riding. The other purpose of this venture is to practice leaps using the wheel pressure to propel oneself up to a rock, or up a slope.

Flatland

The purpose of flatland (also known as freestyle) is to ride a unicycle in different ways, collectively referred to as "freestyle tricks". There are thousands of different ways to ride a unicycle, but the most popular tricks have been categorized in a skill measurement system called the "IUF Achievement Skill Levels".[2] Flatland is typically done indoors in a gymnasium or outside on pavement, where the terrain is smooth and predictable.

Street unicycling

Combines Trials and Freestyle techniques, and is typically done in urban areas. The objective is to perform freestyle tricks on obstacles. The overall difficulty relates not only to the difficulty of the obstacles but also to the difficulty of the tricks. This is different from pure trials because just riding over obstacles is not the ultimate objective; rather, the obstacles are used as props to set up the tricks.

Equipment and safety

Wrist guards

The most common impact points when falling from a unicycle are the hands and wrists. Of all the safety gear, wrist guards receive the most wear and tear.

Knee and elbow pads

The second most common impact point are the knees followed by the elbows.

Helmet

A helmet is especially important with specialty riding like MUni.

Shin guards

Shin guards become a necessary piece of equipment when using metal or pinned pedals. These types of pedals grip the shoes better, but can cause injury to the legs.

Cycling shorts

Padded cycling shorts are designed with a seamless, padded crotch, and long enough legs to extend down past the saddle, making them much more comfortable than "normal" shorts.

Notable unicyclists

• John Foss: World record holder for many unicycling events^[3]
• Kris Holm: Pioneer in Mountain Unicycling
• Kaleigh Grainger: British unicyclist
• Alex Mitchell : Rugby player and subterranean unicyclist
• Christopher Tomes: Most notable in trials unicycling, but competes in muni as well
• Romain Bouschbacher [3](French):French champion off street 2006 and 3eme Europeen at Fluck Denemark
• Peter Tosh: Jamaican Reggae Musician
• Newton Faulkner: musician and recording artist

International Unicycling Convention

The biennial International Unicycling Convention (UNICON) consists of unicycle track and field events — high jump, long jump, novelty racing (1 foot, wheelwalk, coasting, juggling etc.), slowboard, and the obstacle course.^[4] Freestyle events include pairs, individual, club, group, and Standard Skills. The 2006 UNICON was held in Langenthal, Switzerland.

See also

• Bicycle and motorcycle physics
• Robotic unicycle

References

External links

Wikibooks has more on the topic of

Unicycle

• Unicyclist.com - An excellent forum for information about unicycles and where you can read rec.sport.unicycling and other forums
• Unicycling.org - Massive resource of unicycling information
• Unicyclopedia - a wiki containing lots of information about unicycling and unicycles
• Unicyclist.org - Huge archive of clips on unicycle skills
• Unicycle Hockey Video
• Unicycle Pictures - Unicycle picture gallery with free upload