Motorized bicycle


A motorized bicycle is a bicycle with a motor or engine and transmission used either to power the vehicle unassisted, or to assist with pedalling. Since it sometimes retains both pedals and a discrete connected drive for rider-powered propulsion, the motorized bicycle is in technical terms a true bicycle, albeit a power-assisted one. Typically they are incapable of speeds above ; however, in recent years larger motors have been built, allowing bikes to reach speeds of upwards of 113 km/h.
Powered by a variety of engine types and designs, the motorized bicycle formed the prototype for what would later become the motor driven cycle.

Terminology

The term motorized bicycle refers to just a bicycle combining pedal power and internal combustion engine power. However, the term could be used as an umbrella category to refer to bicycles using sources besides pedal power. Electric bicycles technically could be in the category of motorized bicycles but instead of using internal combustion engines as a combination it is driven by electric motors which power from pedals and batteries. Mopeds are also almost motorized bicycles since they function the same way as these vehicles but with engines less than.
The term motorized bicycle should not be confused with motorcycle since this type of vehicle uses a combination of pedal power and engine power whereas motorcycles are purely either internal combustion engine or electric motor powered.

Design and usage

Motorized bicycles have utilized all variety of engines, from internal-combustion two-stroke and four-stroke gasoline engines to electric, diesel, or even steam propulsion. Most motorized bicycles are based or derived from standard general-purpose bicycle frame designs and technologies, although exceptions abound. In addition, modifications to a standard bicycle frame to support motorization may be extensive.
The earliest motorized bicycles were ordinary utility bicycles fitted with an add-on motor and transmission to assist normal pedal propulsion, and it is this form that principally distinguishes the motorized bicycle from a moped or motorcycle. In a day when gasoline engine and transmission designs were in their infancy, and power-to-weight ratios were low, a dual-purpose propulsion system seemed particularly advantageous. As time went on, pedal propulsion was increasingly replaced by constant use of a two or four-stroke gasoline engine. Nevertheless, the concept of using motor assist for the ordinary bicycle has persisted, and the concept has periodically resurfaced over the years, particularly in times of austerity or fuel shortages. In countries where automobiles and/or fuels are prohibitively expensive, the motorized bicycle has enjoyed continued popularity as a primary mode of transportation.
The design of the motorized bicycle varies widely according to intended use. Some motorized bicycles are powerful enough to be self-propelled, without use of the pedals. A development of the motorized bicycle is the moped, which commonly has only a vestigial pedal drive fitted primarily to satisfy legal requirements, and suitable only for starting the engine or for emergency use. The alternate design philosophy to the moped is the so-called motor-assist or pedal-assist bicycle. These machines utilize the pedals as the dominant form of propulsion, with the motor used only to give extra assistance when needed for hills or long journeys.

History

The two-wheeled pedal powered bicycle was first conceived in Paris in the 1860s. By 1888, John Dunlop's pneumatic tire and the chain drive made possible the safety bicycle, giving the bicycle its modern form.
The origins of the motorized bicycle or motorbike can be traced back to the latter part of the 19th century when experimenters began attaching steam engines to bicycles, tricycles, and quadracycles. The first true motorized bicycle is generally considered to be the French Michaux-Perreaux steam velocipede of 1868. The Michaux-Perreaux was followed by the American Roper steam velocipede of 1869, built by Sylvester H. Roper of Roxbury, Massachusetts. Roper demonstrated his machine at fairs and circuses in the eastern United States in 1867, and built a total of 10 examples. These early attempts at propelling a bicycle by means other than the human body were not successful, either practically or commercially. It was not until the 1890s, with the advent of the gasoline-powered internal combustion engine, that the motorized bicycle could be considered a practical machine.
One of the first gas motor-assisted bicycle designs was the Millet motorcycle developed by Félix Millet in France in 1892. Millet's designs had both pedals and a fixed-crankshaft radial engine built into the back wheel.
In 1896, E. R. Thomas of Buffalo, New York, began selling gasoline engine kits for propelling ordinary bicycles. After forming the Thomas Motor Company, he began selling complete motor-assisted bicycles under the name Auto-Bi. The Auto-Bi is generally considered to be the first production motorized bicycle made in the United States.
The 1900 Singer Motor Wheel was a wheel incorporating a small ICE powerplant that could be substituted for the front wheel of a bicycle. A later design, the 1914 Smith Motor Wheel, was attached to the rear of a bicycle by means of an outrigger arm, a design later taken up by Briggs & Stratton.
In Belgium, the Minerva company, later known for luxury cars, started out manufacturing standard safety bicycles in 1897, before expanding into light cars and "motocyclettes" from 1900. They produced lightweight clip-on engines that mounted below the front down tube, specifically for Minerva bicycles, but also available in kit form suitable for almost any bicycle. The engine drove a belt turning a large gear wheel attached to the opposite side of the rear wheel as the chain. By 1901 the kit engine was a unit developing, comfortably cruising at at 1,500 rpm, capable of a top speed of, and getting fuel consumption in the range of. These kits were exported around the world to countries including the United Kingdom, France, Germany, the Netherlands, Australia, and other British territories of the time.
As engine power increased, frame ruptures became increasingly common, and by 1903 Minerva had developed an in-frame design with the engine mounted above the bottom bracket, while still also offering the clip-on kit. From 1904 Minerva began focusing more on car production, and while development and production of the Minerva motorized bicycles continued through to about 1909, they became a less and less significant part of the company.
In England, the Phelon & Rayner motorized bicycle was introduced in 1901, and was sold through 1903. The original Phelon & Rayner machine used a, gasoline engine mounted to a standard 28-inch bicycle frame.
In the United States, the California Motor Company was formed in 1901 to sell complete gasoline-engine motorbikes in San Francisco, Oakland, and San Jose. The company began with a 200 cc single-cylinder, 1.5-horsepower, four-stroke engine designed by R.C. Marks. Mounted to a standard bicycle frame, the California could reach speeds of approximately 25 mph. The California weighed around 75-80 pounds, and featured a leading-link front fork, a leather spring saddle, a front Duck roller brake, and an Atherton rear coaster brake. A leathern belt-drive directly connected the engine output shaft to the rear wheel. During the summer of 1903, George A. Wyman rode a, California from San Francisco to New York City, becoming the first person to cross the North American continent aboard a motor vehicle.
As early as 1903, motorized bicycles were being fitted with larger and heavier loop frames designed to specifically accommodate larger displacement engines, which produced higher speeds. These new motorbike frame designs soon incorporated a new riding position that no longer centered the rider over the pedals, but instead moved the rider's feet forward, where they rested on pegs or platforms. The new riding position was designed to increase rider comfort and control when using the motor for propulsion, and soon owners began relying on the gasoline motor for all but emergency use. Front suspension and rear suspension increased control at high speeds. By 1915, some manufacturers were omitting pedal propulsion entirely, resulting in the introduction of the first true modern motorcycle.
At the same time, purpose-built motorbikes like the Derny and VéloSoleX, with stronger frames and sometimes with only token ability to be wholly human-powered were introduced in France. Many years later, manufacturers would re-introduce this concept as the moped, a small motorcycle fitted with pedals that can be used as a starting aid but which cannot, practically, be ridden under pedal power alone.
In France, the gasoline-powered motorized bicycle, known popularly as the vélomoteur or vélomoto was popular during the 1930s, and continued to be widely sold in early postwar years as a means of transportation during a period of gasoline shortages and limited automobile production.
In the 1930s, the United Kingdom and its former colonies also developed "clip-on" motors for bicycles, followed by the "Autocycle" with a purpose-built frame incorporating pedals and a two-stroke engine, but without a gearbox. Autocycle manufacturers were well established in countries such as Britain and Australia before World War II.
In 1939, the American bolt-on Whizzer gas-engined bicycle kit was introduced, utilizing a 138 cc side-valve four-stroke engine, the first whizzer was of the friction drive variety, but was soon replaced with belt drive. Despite some initial engine reliability issues, the Whizzer enjoyed modest popularity during World War II due to fuel and automobile shortages, and was used by war plant workers and others with priority for transportation. After the war, the Whizzer became popular with youth who desired faster speeds from their heavy cruiser-framed Schwinn bicycles. In 1949, the company introduced a complete production bike, the Pacemaker. Sales of the Whizzer conversion kits continued until 1962. In the United Kingdom, the motorized bicycle saw a resurgence of popularity and such bolt-on motors as the Cyclaid and the Cyclemaster motor wheel saw brief periods of immense popularity. The Cyclemaster, which was a hub motor that could be fitted to an ordinary bike, started at 25 cc, but later the size went up to 32 cc.
Elsewhere in Europe, the motorized bicycle continued to be popular, particularly in France and Italy. An Italian manufacturer, Vincenti Piatti, designed a 50 cc engine for driving portable lathes and this was also used to power a bicycle frame in the form of the Mini Motore. Piatti later licensed the design to Trojan for production in Britain as the Trojan Minimotor. In West Germany, a compression-ignition engine kit using an 18 cc variable head engine made by Lohmann was produced during the 1950s. In France, where postwar reconstruction, taxes, and fuel shortages limited automobile access, motorized bicycle kits and complete models were produced by a variety of smaller manufacturers, often using a two-stroke gasoline engine mounted above the front wheel. In 1946, production of the very successful French VELOSOLEX commenced, continuing until 1988. The VéloSoleX was a mass-produced motorized bicycle that used a tire roller to the front wheel. After French production ceased, the VELOSOLEX continued to be produced in China and Hungary. An in-wheel gasoline engine was used on the Honda P50 moped, which ceased production in 1968. The velomoteur and motor scooter enjoyed a second renaissance in the 1960s and 1970s as a new generation of youth discovered they could ride a motorized vehicle without need of a driver's license. Other countries had relaxed licensing requirements, e.g. lower age limits for motorized bicycles, which increased their popularity.
In the USSR, a deficiency of any vehicles in the market led to a great increase of cheap 50cc mopeds and kits production. Sales of the mopeds and kits reached approximately a half million per year in the later 70s. As to technical level, it was analogous to pre-WW2 German models, with minimal changes made to later 80s. The only clip-on kit engine was "D" series, a single-speed chain-driven 45cc 2-stroke motor with manual clutch and a rotary slide valve in a crankshaft. It was destined for clipping into a classic twin-diamond bike frame. As of the present day, it is still widely produced by some Chinese factories like Jiangdu in a piston distribution version, and has some popularity even in the United States.
During the 1960s, the moped craze arrived in the United States, the United Kingdom, and other countries. Mopeds had been produced for years in France and Italy, but were largely unknown in other countries. The moped's surge in popularity was motivated by the arrival of new machines produced in Japan by Honda, Yamaha, and other manufacturers, which could be operated without a driver's license and with a minimum of effort to meet existing regulation by the authorities. The new moped designs were really low-powered motorcycles, equipped with pedals largely to meet legal requirements. Most could be pedaled only with difficulty over short distances on level ground.