The unicycle has been around since the late 19th century. Although it was for sale to the general public, most unicycles were used by circus performers, rather than by "regular folks." Things changed in the 1980s, when unicycle design started to change to introduce more variations that appealed to the general population. Aside from the standard unicycles, there are also seatless unicycles as well as the "giraffe unicycle," where the seat can be as high as 5 feet from the ground.
Beginners might need to start with the smallest unicycle available, the 20-inch wheeler. One of the biggest challenges of riding a unicycle is learning to mount it and then maintain balance on it. Choosing a tall unicycle makes the mounting more difficult and also increases the fear of falling off. A 20-inch wheeler is the slowest of the normal-size unicycles. An experienced rider might be able to reach high speeds of 8 mph as a maximum.
Size of Wheel
Unicycles come in different heights. The height of a unicycle is determined by the size of its wheel. The bigger the wheel the more surface it will cover every time you pedal and the wheel rotates. This means a 36-inch wheel will go much faster than a 20-inch wheel. The average speed for a 20-inch unicycle is 5 mph, while a 36-inch unicycle can ride at an average of 11 mph. An experienced rider could technically reach speeds of up to 22 mph on a 36-inch unicycle. Mini-unicycles, with wheels under 20 inches, are more for showmanship than for riding, as they're too small to provide riding comfort.
Even, flat surfaces like pavement will allow for better speeds. When doing mountain unicycling or riding on uneven surfaces, you're likely to slow down. According to unicycle expert John Foss on his website Unicycling.com, an average high speed of 13 to 15 mph is feasible on dirt roads.
Unicycles have no chains and no gears. This means the speed at which you ride is entirely dependent on how fast you pedal on a flat surface. You will need to maintain a minimum speed in order to keep your balance, but how much faster you ride depends on how much you can handle. For example, the average speed for riding a 29-inch unicycle is 7 mph. If you're not in shape, you might find that you can only manage 5 mph without getting out of breath or losing your balance. Somebody in good shape could reach the high end of the spectrum, at about 14 mph for that wheel size.