Unicycle trials
Encyclopedia
Unicycle trials is a form of unicycling which involves participants attempting to ride a unicycle
over obstacles without any part of the rider touching the ground.
The obstacles traversed can be set up specifically for the purpose of unicycle trials, but are often walls, railings, ledges and other "street furniture" found in an urban environment. The sport is derived from (or at least inspired by) bike trials and motorcycle trials.
Obstacles are traversed using various moves. Hopping is achieved by suddenly forcing the unicycle pedals downwards while holding the seat, the reactive forces resulting from the compression of the tyre lift the unicycle into the air. Jumping is a similar to hopping, except that the unicycle seat is held in front of the rider to allow greater height to be achieved. Pedal grabs and crank grabs involve a hop or jump to land the unicycles pedal
or crank
on the edge of an object, and then a second hop or jump to land the unicycle fully on the object.
Although unicycle trials can be performed on a standard unicycle, many are not designed for the forces which are caused by unicycle trials. A trials unicycle is built with unicycle trials in mind, and is therefore designed to better cope with these stresses.
and cranks
.
The wheel diameter
on a trials unicycle is usually 19", as this allows greater maneuverability due to the short circumference
of the wheel. Most Trials unicycles come with 19" rear rims as used on 20" (or mod) trials bicycles. This allows for larger tyres to be fitted which can help provide bounce and preload for jumping, and aid stability being generally quite wide (some up to 2.5 inches).
A smaller wheel also means the unicycle is lighter, although some riders prefer larger wheels. The tire is generally wide and thick, giving a large air volume. This is to cushion drops and allow large hops and jumps. The tire will often have a deep tread to allow greater grip to obstacles. Strong high tension spokes and a strong rim wheel rim is used to prevent the wheel from deforming under the great stresses exerted on it by jumping. Unicycle wheels have to withstand large lateral stresses because, unlike in conventional riding, the rider may jump sideways. Many trials unicycles have a splined hub and cranks, as this design tends to be more resistant to bending and breaking than the more common cotterless, or square taper, equivalent. Long cranks give the rider extra torque and pedals with a large amount of grip (often with pins or teeth) are used to prevent the rider's feet from slipping. Unicycles with shorter cranks are generally referred to as street unicycles, as they let the rider keep up their momentum easier and do smooth tricks. Whereas Trials unicycles usually have longer cranks that are better for hopping, as the rider has better control of the rotation of the wheel, and can therefore keep the unicycle from slipping out from under him.
Unicycle
A unicycle is a human-powered, single-track vehicle with one wheel. Unicycles resemble bicycles, but are less complex.-History:One theory of the advent of the unicycle stems from the popularity of the penny-farthing during the late 19th century...
over obstacles without any part of the rider touching the ground.
The obstacles traversed can be set up specifically for the purpose of unicycle trials, but are often walls, railings, ledges and other "street furniture" found in an urban environment. The sport is derived from (or at least inspired by) bike trials and motorcycle trials.
Obstacles are traversed using various moves. Hopping is achieved by suddenly forcing the unicycle pedals downwards while holding the seat, the reactive forces resulting from the compression of the tyre lift the unicycle into the air. Jumping is a similar to hopping, except that the unicycle seat is held in front of the rider to allow greater height to be achieved. Pedal grabs and crank grabs involve a hop or jump to land the unicycles pedal
Bicycle pedal
A bicycle pedal is the part of a bicycle that the rider pushes with their foot to propel the bicycle. It provides the connection between the cyclist's foot or shoe and the crank allowing the leg to turn the bottom bracket spindle and propel the bicycle's wheels...
or crank
Crank (mechanism)
A crank is an arm attached at right angles to a rotating shaft by which reciprocating motion is imparted to or received from the shaft. It is used to change circular into reciprocating motion, or reciprocating into circular motion. The arm may be a bent portion of the shaft, or a separate arm...
on the edge of an object, and then a second hop or jump to land the unicycle fully on the object.
Although unicycle trials can be performed on a standard unicycle, many are not designed for the forces which are caused by unicycle trials. A trials unicycle is built with unicycle trials in mind, and is therefore designed to better cope with these stresses.
Trials unicycle
A trials unicycle is a 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 pedalsBicycle pedal
A bicycle pedal is the part of a bicycle that the rider pushes with their foot to propel the bicycle. It provides the connection between the cyclist's foot or shoe and the crank allowing the leg to turn the bottom bracket spindle and propel the bicycle's wheels...
and cranks
Crankset
The crankset or chainset , is the component of a bicycle drivetrain that converts the reciprocating motion of the rider's legs into rotational motion used to drive the chain, which in turn drives the rear wheel...
.
The wheel diameter
Diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...
on a trials unicycle is usually 19", as this allows greater maneuverability due to the short circumference
Circumference
The circumference is the distance around a closed curve. Circumference is a special perimeter.-Circumference of a circle:The circumference of a circle is the length around it....
of the wheel. Most Trials unicycles come with 19" rear rims as used on 20" (or mod) trials bicycles. This allows for larger tyres to be fitted which can help provide bounce and preload for jumping, and aid stability being generally quite wide (some up to 2.5 inches).
A smaller wheel also means the unicycle is lighter, although some riders prefer larger wheels. The tire is generally wide and thick, giving a large air volume. This is to cushion drops and allow large hops and jumps. The tire will often have a deep tread to allow greater grip to obstacles. Strong high tension spokes and a strong rim wheel rim is used to prevent the wheel from deforming under the great stresses exerted on it by jumping. Unicycle wheels have to withstand large lateral stresses because, unlike in conventional riding, the rider may jump sideways. Many trials unicycles have a splined hub and cranks, as this design tends to be more resistant to bending and breaking than the more common cotterless, or square taper, equivalent. Long cranks give the rider extra torque and pedals with a large amount of grip (often with pins or teeth) are used to prevent the rider's feet from slipping. Unicycles with shorter cranks are generally referred to as street unicycles, as they let the rider keep up their momentum easier and do smooth tricks. Whereas Trials unicycles usually have longer cranks that are better for hopping, as the rider has better control of the rotation of the wheel, and can therefore keep the unicycle from slipping out from under him.