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A tricycle is a three-wheeled machine used for riding. Tricycles were an adaptation of the velocipede, and were first introduced around about 1878 as a substitute for the high bicycle. Most tricycles are steered directly by one wheel in front, though some have been made with two steering wheels abreast and driven by a single wheel behind. Tricycles operate on the same principle as the bicycle but by the 1920s were very little used in Britain except in special forms, such as those propelled by hand for use by people unable to use their legs, and the carrier-tricycle which was fitted with a box for the delivery of goods from shops etc. Later, tricycles were revived for use by children.
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A tricycle is a three-wheeled machine used for riding. Tricycles were an adaptation of the velocipede, and were first introduced around about 1878 as a substitute for the high bicycle. Most tricycles are steered directly by one wheel in front, though some have been made with two steering wheels abreast and driven by a single wheel behind. Tricycles operate on the same principle as the bicycle but by the 1920s were very little used in Britain except in special forms, such as those propelled by hand for use by people unable to use their legs, and the carrier-tricycle which was fitted with a box for the delivery of goods from shops etc. Later, tricycles were revived for use by children.
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A bicycle is a two wheeled vehicle driven by the riders feet pushing on cranks or pedals. A common misconception is that the earliest form of bicycle was the dandy-horse, which was pushed along by the rider's feet. However, while both the dandy-horse and the later bicycle are both velocipedes, the dandy-horse is not propelled by cranks.
The first bicycle was introduced to England from France in 1868, and comprised two solid wheels of equal size fitted to a frame, much like a modern bicycle in appearance, with a saddle fitted in the centre and propelled by cranks attached to the front wheel. This vehicle provided such a bumpy ride to the rider that it became popularly known as 'the bone-shaker'. Later came the Penny-Farthing with pedals fixed to the large front wheel which was made large to achieve high speeds. Later still, around 1895, came the safety bicycle with pedals driving the rear wheel by way of a chain, and the rider sitting upon a saddle set back from the front wheel so as to reduce the chances of falling forwards over the handlebars, from this developed the Raleigh bicycle design of 1900 which forms the basis of the modern bicycle. In 1888 the two-person tandem bicycle was invented.
In 1906 it was reported that speeds of 50 mph were attained on a bicycle. Around the same time, slightly earlier, the motorised bicycle (motorcycle or motorbike) was invented.
A typical bicycle is comprised of several parts. The principal and essential being: the frame, front forks, wheels, pedals, saddle, handlebars, chain and brakes. The largest part of the bicycle is the frame, and these vary in design depending upon the specialised intention of the bicycle.
A frame for a BMX bicycle being small, heavily braced and made of aluminium. The frame for BMX xyxling needs to be strong so as to endure the stresses of the bumpy ride, and the saddle low as competitors never sit down during a competition and as such they need space to sprint and jump with ease.
Cross-Country cycle frames are generally made of aluminium and carbon-fibre so as to be light weight. They are relatively small frames to allow quick and easy mounting and dismounting off road, and strong to endure off-road bumpy conditions. The smaller frames are often compensated for by having a longer seat post to allow a normal height saddle position.
The cycle speedway bicycle frame is designed primarily for strength, and as such is typically made from steel or aluminium.
Road racing bicycle frames are designed to be light and stiff. Traditionally they ewre made of steel, but by the start of the 21st century carbon fibre was being used for the more expensive models as this offered the same stiffness at reduced weight. The design of the tubes also developed over time, tubes becoming of a larger diameter, but thinner walls, to allow the same stiffness with reduced weight.
Bicycles are fitted with various types of brake, the most popular being the calliper, cantilever, hydraulic or disc and the V brake. The most common form of brake found on leisure bicycles, is that form used also on road racing bicycles. The calliper brake. Calliper brakes are a very efficient means of rim braking and basically comprise two blocks of rubber or plastic which are squeezed onto the wheel rim when the brake lever is squeezed by the ride.
Cantilever brakes operate on the same principal as calliper brakes, but are of a slightly different design at the wheel end, offering increased clearance between the tyre and the brake pads and as such are frequently employed for cyclo-cross bicycles and mountain bikes.
The most efficient form of rim brake is the V brake. The V brake also offers the most clearance of any rim braking system, and is most often found on mountain bikes.
Hydraulic or disc brakes are the most efficient and powerful form of bicycle brake. They use the wheel hub to brake, rather than the rim. Disc brakes offer the most clearance, and as such are used on mountain bikes, but are also expensive to fit and maintain.
Bicycle wheels are generally of one of three types. The most common and traitional bicycle wheel is the spoked wheel, comprising a rim connected to the central bub by a series of thin metal rods known as spokes. Spoked wheels are light in weight. Less common than spoked wheels, but offering greater strength and durability at the expense of weight are mag wheels which comprise a rim attached to the hub by a few, thick solid plastic bars. Solid wheels, also known as disc wheels, are made from composite material or carbon fibre are very strong, stiff, aerodynamic and very expensive. They are rarely used except as rear wheels in time-trialing and track racing.
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The dandy-horse was an early velocipede or cycle. It resembled a bicycle, but hadn't any pedals and so the rider propelled it by pushing it along with his feet on the ground.
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Enigmarelle was possibly the first robot. It was an automaton constructed of 365 different parts, and actuated by electricity. The figure rode a bicycle, wrote its name on a blackboard and performed other tasks similar to a human being. Enigmarelle was exhibited at the London Hippodrome in June 1905.
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A moped is a motorised bicycle developed during the1960s. Mopeds are equipped with motors of up to two horsepower, and they travel at maximum speeds of only about 50 km/hr. Their advantage lies in their fuel efficiency. The pedals are used only to start and assist the motor.
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The Presta vale or French valve, is a popular and commonly used bicycle tyre valve. The Presta valve is a slim valve with a built-in captive-nut valve cap, which must be unscrewed before you can pump the tyre up. Since there is no spring in a Presta valve, valve nut must be tightened after inflating the tyre, or the air will escape out of the tyre.
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A saddle is a contrivance of wood and leather securely bound with a girth or leather straps to the back of a horse, to serve as a seat for the rider or to carry the weight of the shafts of a vehicle. Other forms of saddle are used for other animals, such as camels and oxen. The seat of a bicycle and motorcycle is also called a saddle.
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The Schrader valve is a type of bicycle tyre valve the same as the standard automotive-style tyre valve found on cars.
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A tandem is a bicycle with two seats one behind the other. Other multi-person bicycles include the triplet, with three seats, the quadrupet with four and the quintet with five.
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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