Motorcycle

A pair of motorcycles packed for touring

A motorcycle (bike, motorbicycle, cycle or motorbike) is a single-track, two-wheeled motor vehicle powered by an engine. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions. In many parts of the world, motorcycles are among the least expensive and most widespread forms of motorised transport.

Contents

History

Main article: Motorcycle history
Replica of the Daimler-Maybach Reitwagen
A 1913 Fabrique National in-line four with shaft drive from Belgium
A pre-war Polish Sokół 1000

Arguably, the first motorcycle was designed and built by the German inventors Gottlieb Daimler and Wilhelm Maybach in Bad Cannstatt (since 1905 a city district of Stuttgart) in 1885.[1] The first petroleum-powered vehicle, it was essentially a motorised bicycle, although the inventors called their invention the Reitwagen ("riding car"). However, if a two-wheeled vehicle with steam propulsion is considered a motorcycle, then the first one may have been American. One such machine was demonstrated at fairs and circuses in the eastern U.S. in 1867, built by Sylvester Howard Roper of Roxbury, Massachusetts.[1]

In 1894, Hildebrand & Wolfmüller became the first motorcycle available for purchase.[2] In the early period of motorcycle history, many producers of bicycles adapted their designs to accommodate the new internal combustion engine. As the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle producers increased.

An historic 1941 Crocker

Until the First World War, the largest motorcycle manufacturer in the world was Indian, producing over 20,000 bikes per year. By 1920, this honor went to Harley-Davidson, with their motorcycles being sold by dealers in 67 countries. In 1928, DKW took over as the largest manufacturer.

After the Second World War, the BSA Group became the largest producer of motorcycles in the world, producing up to 75,000 bikes per year in the 1950s. The German company NSU Motorenwerke AG held the position of largest manufacturer from 1955 until the 1970s.

NSU Sportmax streamlined motorcycle, 250 cc class winner of the 1955 Grand Prix season

In the 1950s, streamlining began to play an increasing part in the development of racing motorcycles and held out the possibility of radical changes to motorcycle design. NSU and Moto-Guzzi were in the vanguard of this development both producing very radical designs well ahead of their time.[3] NSU produced the most advanced design, but because of the deaths of four NSU riders in the 1954–1956 seasons, they abandoned further development and quit Grand Prix motorcycle racing.[4] Moto-Guzzi produced competitive race machines, and by 1957 nearly all the Grand Prix races were being won by streamlined machines.

From the 1960s through the 1990s, small two-stroke motorcycles were popular worldwide, partly as a result of East German Walter Kaaden's engine work in the 1950s.[5]

Today, the Japanese manufacturers, Honda, Kawasaki, Suzuki, and Yamaha dominate the motorcycle industry, although Harley-Davidson still maintains a high degree of popularity in the United States. Apart from these high capacity motorcycles, there is a very huge market for low capacity (less then 300 cc) motorcycles, mostly concentrated in Asian and African countries. This area is dominated by mostly Indian companies with Hero Honda being the world's largest manufacturer of two wheelers. Its Hero Honda Splendor model is the highest selling motorcycle in automotive history, having sold more then 8.5 million to date.[6]

A 2006 Honda Hero

Recent years have also seen a resurgence in the popularity of several other brands sold in the U.S. market, including BMW, KTM, Triumph, Aprilia, Moto-Guzzi, MV Agusta and Ducati.

Outside of the U.S., these brands have enjoyed continued and sustained success, although Triumph, for example, has been re-incarnated from its former self into a modern world-class manufacturer. In overall numbers, however, the Chinese currently manufacture and sell more motorcycles than any other country and exports are rising.

Additionally, the small-capacity scooter is very popular through most of the world. The Piaggio group of Italy, for example, is one of the world's largest producers of two-wheeled vehicles.

Technical aspects

A Suzuki GS500 with a clearly visible frame (painted silver).

Construction

Main article: Motorcycle construction

Motorcycle construction is the engineering, manufacturing, and assembly of components and systems for a motorcycle which results in performance, cost and aesthetics desired by the designer. With some exceptions, construction of modern mass-produced motorcycles has standardised on a steel or aluminium frame, telescopic forks holding the front wheel, and disc brakes. A gasoline powered engine typically consisting of between one and four cylinders (and less commonly, up to eight cylinders) coupled to a manual five- or six-speed sequential transmission drives the swingarm-mounted rear wheel by a chain, driveshaft or belt.

Fuel economy

Motorcycle fuel economy benefits from the relatively small mass of the vehicle. This, of course, relates to how the motorcycle is used. One person on a small motorcycle travelling a short distance is generally very economical. However a large motorcycle generally has bad aerodynamics compared with a typical car, poor aerodynamics of exposed passengers and engines designed for goals other than fuel economy can work to reduce these benefits. Riding style has a large effect on fuel economy.

Fuel economy varies greatly with engine displacement and riding style [7] ranging from a low of 29 mpg-US (12 km/l/35 mpg-imp) reported by a Honda VTR1000F rider,[8] to 107 mpg-US (45 km/l/129 mpg-imp) reported for the Verucci Nitro 50 cc Scooter.[9] A specially designed Matzu Matsuzawa Honda XL125 achieved 470 mpg-US (200 km/l/560 mpg-imp) "on real highways - in real conditions."[10]

Dynamics

Racing motorcycles leaning in a turn.
Main article: Bicycle and motorcycle dynamics

Different types of motorcycles have different dynamics and these play a role in how a motorcycle performs in given conditions. For example, a shorter wheelbase would generally make a bike lean faster and would be quicker around corners compared to a longer wheelbase. Longer wheelbase on the other hand provides more stability in a straight line.

Motorcycles must be leaned in order to make turns. This lean is induced by the method known as countersteering, in which the rider presses on the handlebars on the side of the desired direction of turn, but 'steering' the bars in the opposite direction. Because it is counter-intuitive this practice is often very confusing to novices—and even to many experienced motorcyclists.[11]

Short wheelbase motorcycles, such as sport bikes, can generate enough torque at the rear wheel, and enough stopping force at the front wheel, to lift the opposite wheel off the pavement. These actions, if performed on purpose, are known as wheelies and stoppies respectively. If carried past the point of recovery the resulting upset is known as "looping" the vehicle.

Additions

Various features and accessories may be attached to a motorcycle either from the factory or by users.

Fairing on a Honda Gold Wing
Fairing

A plastic or fibreglass shell, known as a "fairing", is placed over the frame on some models to shield the rider from the wind, aid in aerodynamics and protect engine components in an accident. Drag is the major factor that limits motorcycle speed. As evident in the streamlined appearance of new performance motorcycles, there is much aerodynamic technology included in the design. Since the 1958 FIM ban on motorcycle designs that cover the wheels or the rider, e.g., "dustbin" fairings, no major manufacturer has provided fairing to overcome the effect of the turbulence caused by the spinning front wheel, which prevents the motorcycle from cutting a clean path through the air. "Dustbin" fairings can improve aerodynamic performance without substantially compromising the rider's ability to control the machine, if the fairing is designed and tested for the effects of side winds.

Modern fairings on touring and sport-touring motorcycles dramatically improve a rider's comfort and attention on long rides by reducing the effect of the wind and rain on the body. They also help keep a rider warm in cold weather or high wind chill conditions, reducing hypothermia.

An example of a fairing on a Honda CBR1000F
Windscreen

Also called windshields or screens, windscreens can be built into a fairing or be attached to an otherwise unfaired bike. They are usually made from transparent high-impact acrylic plastic. They may be shaped specifically to direct air flow over or around the head of the rider even if they are much shorter than the seated rider. Some motorcycles have electric screens, introduced on the 1986 BMW K100LT, which raise and lower the screen with the push of a button to the optimum height for conditions.

In the absence of a fairing or screen, a phenomenon known as the windsock effect occurs at speeds above 100 km/h (62 mph), where the rider becomes a major source of drag and is pushed back from the handlebars, tiring the rider. However, these motorcycles still effectively push their way through the atmosphere with brute force. A cabin cycle, which has a hull that wraps around the basic cycle frame, solved the problem of aerodynamics by isolating driver from outside air.

Craven's Golden Arrow panniers
Saddlebags or panniers

Saddlebags or panniers mount on either side of the rear wheel behind the saddle to carry parts, tools, and/or travel gear. They can be made of fiberglass, ABS, leather, Cordura, or other appropriate sturdy material. They are normally standard items on touring motorcycles but are usually optional on other types of motorcycles. They can be model-specific and available from a motorcycle's manufacturer, or after-market and designed to fit on numerous models.

Heated handgrips on a BMW
Heated hand grips/seats

Since motorcycles lack climate control or proper protection from the wind, some manufacturers offer heated seats or hand grips to relieve the discomfort of low temperatures experienced during night riding or the colder months. They can also be added on as after-market accessories and are powered by the bike's electrical system.

Luggage rack

A common addition to many bikes is an attachment onto which bags or other luggage can be fastened. This removes the need for rider backpacks and is generally a more secure and safe way to add carrying capacity to a motorcycle.

Sidecar
IMZ-Ural motorcycle with sidecar

A sidecar is a one-wheeled device attached to the side of a motorcycle, producing a three-wheeled vehicle. Early sidecars were removable devices that could be detached from the motorcycle. Sidecars gradually superseded forecars and trailers. The forecar comprised a two-wheeled attachment at the front of the motorcycle. The trailer was just that, pulling the passenger along behind. In neither case could rider and passenger converse easily, and early sidecars were often called 'sociable' attachments.

Trailer hitch

A trailer hitch or tow hitch is a device mounted on a motorcycle that enables it to tow a motorcycle trailer, usually to haul additional gear. No motorcycle manufacturer recommends trailer towing because it creates safety hazards for motorcyclists.

Trunk

A motorcycle trunk is a storage compartment in the vicinity of the seat, other than panniers or saddlebags. A trunk mounted above and at the rear of the seat is called a top box.

Social aspects

Main article: Motorcycling

Popularity

Recent years have seen an increase in the popularity of motorcycles. In the USA, registrations increased by 51% between 2000 and 2005.[12] This is mainly attributed to increasing fuel prices and urban congestion,[13] but is also partly due to television programmes such as reality show American Chopper, or adventure-travel shows such as Long Way Down.

Subcultures

A motorcycle rally in Ontario

Around the world, motorcycles have historically been associated with subcultures. Some of these subcultures have been loose-knit social groups such as the cafe racers of 1950s Britain, and the Mods and Rockers of the 1960s. A few are believed to be criminal gangs.

Social motorcyclist organisations are popular and are sometimes organised geographically, focus on individual makes, or even specific models. Example motorcycle clubs include: American Motorcyclist Association, Harley Owners Group, Moto Guzzi National Owners Club, Gold Wing Road Riders (GWRRA), and BMW MOA.

Many motorcycle organisations raise money for charities through organised events and rides. Some organisations hold large international motorcycle rallies in different parts of the world that are attended by many thousands of riders.

Some other motorcycle organisations exist only for the direct benefit of others. Bikers Against Child Abuse (BACA) is one example. BACA assigns members to individual children to help them through difficult situations, or even stay with the child if the child is alone or frightened.[14]

In recent decades, motorcyclists have formed political lobbying organisations in order to influence legislators to introduce motorcycle-friendly legislation. One of the oldest such organisations, the British Motorcycle Action Group, was founded in 1973 specifically in response to helmet compulsion, introduced without public consultation.[15] In addition, the British Motorcyclists Federation (BMF), originally founded in 1960 as a reaction to the public perception of motorcyclists as leather-jacketed hooligans, has itself moved into political lobbying.

Likewise, the U.S. has ABATE, which, like most such organisations, also works to improve motorcycle safety, as well as running the usual charity fund-raising events and rallies, often for motorcycle-related political interests.[16]

Mobility

While people choose to ride motorcycles for various reasons, those reasons are increasingly practical, with riders opting for a powered two-wheeler as a cost-efficient alternative to infrequent and expensive public transport systems, or as a means of avoiding or reducing the effects of urban congestion.[17] In places where it is permitted, lane splitting, also known as filtering, allows motorcycles to use the space between vehicles to move through stationary or slow traffic.[18]

In the UK, motorcycles are exempt from the £8 per day London congestion charge other vehicles must pay to enter the city during the day. Motorcycles are also exempt from toll charges at some river crossings, such as the Severn Bridge, Dartford Crossing, and Mersey Tunnels. Some cities, such as Bristol, allow motorcycles to use bus lanes and provide dedicated free parking. In the United States, those states that have high-occupancy vehicle lanes also allow for motorcycle travel in them. Other countries have similar policies.

In New Zealand motorcycle riders are not required to pay for parking[19] that is controlled by a barrier arm; the arm does not occupy the entire width of the lane, and the motorcyclist simply rides around it.[20] Many carparks controlled in this way supply special areas for motorcycles to park, so as not to unnecessarily consume spaces.

In many cultures motorcycles are the primary means of motorised transport. According to the Taiwanese government, for example, "the number of automobiles per ten thousand population is around 2,500, and the number of motorcycles is about 5,000."[21]

Safety

Main articles: Motorcycle safety and Motorcycle safety clothing

Motorcycles have a higher rate of fatal accidents than automobiles. United States Department of Transportation data for 2005 from the Fatality Analysis Reporting System show that for passenger cars, 18.62 fatal crashes occur per 100,000 registered vehicles. For motorcycles this figure is higher at 75.19 per 100,000 registered vehicles – four times higher than for cars.[22] The same data show that 1.56 fatalities occur per 100 million vehicle miles travelled for passenger cars, whereas for motorcycles the figure is 43.47 – 28 times higher than for cars. Furthermore for motorcycles the accident rates have increased significantly since the end of the 1990s, while the rates have dropped for passenger cars.

Wearing a motorcycle helmet reduces the chances of death or injury in a motorcycle crash

The two major causes of motorcycle accidents in the United States are: motorists pulling out or turning in front of motorcyclists and violating their rights-of-way and motorcyclists running wide through turns. The former is sometimes called a SMIDSY, an acronym formed from the motorists' common response of "Sorry mate, I didn't see you".[23] The latter is more common when motorcyclists mix drinking with riding.[24] Motorcyclists can anticipate and avoid some of these crashes with proper training, increasing their conspicuousness to other traffic, and separating alcohol and riding.

The United Kingdom has several organisations which are dedicated to improving motorcycle safety by providing advanced rider training over and above what is necessary to pass the basic motorcycle test. These include the Institute of Advanced Motorists (IAM) and the Royal Society for the Prevention of Accidents (RoSPA). Along with increased personal safety, riders with these advanced qualifications often benefit from reduced insurance costs.

An MSF rider course for novices

Motorcycle Safety Education is offered throughout the United States by organisations ranging from state agencies to non-profit organisations to corporations. The courses, designed by the Motorcycle Safety Foundation (MSF), include a Basic Rider Course, an Intermediate Rider Course and an Advanced Rider Course.

In the UK (except Northern Ireland) and some Australian jurisdictions, such as New South Wales,[25] the Australian Capital Territory[26] and the Northern Territory,[27] it is compulsory to undertake a rider training course before being issued a Learners Licence.

In Canada, motorcycle rider training is compulsory in Quebec and Manitoba only, but all provinces and territories have Graduated Licensing programs which place restrictions on new drivers until they have gained experience. Eligibility for a full motorcycle license or endorsement for completing a Motorcycle Safety course varies by province. The Canada Safety Council, a non-profit safety organisation, offers the Gearing Up program across Canada and is endorsed by the Motorcycle and Moped Industry Council.[28] Training course graduates may qualify for reduced insurance premiums.

Types

There are three major types of motorcycle: street, off-road, and dual purpose. Within these types, there are many different sub-types of motorcycles for many different purposes.

Street

Harley-Davidson Softail Heritage Classic. A typical "cruiser" design
An Italian 125 cc Cagiva Planet.
A "standard" or "naked" motorbike
A Kawasaki ZX-7RR sport bike
A BMW R1200RT touring bike

Off-road

Dual-purpose

The popular Kawasaki KLR650 dual-purpose motorcycle

Motorcycle rider postures

The motorcyclist's riding position depends on rider body-geometry (anthropometry) combined with the geometry of the motorcycle itself — falling along a spectrum of three basic postures.[29]

Important factors of a motorcycle's ergonomic geometry that determine the seating posture include the height, angle and location of footpegs, seat and handlebars. Likewise, factors in a rider's physical geometry that contribute to seating posture include torso, arm, thigh and leg length, and overall rider height.

Legal definitions and restrictions

See also: Restrictions on motorcycle use on freeways

A motorcycle is broadly defined by law in some countries for the purposes of registration, taxation or licensing riders as a two-wheel motor vehicle "fit to drive." Other countries distinguish between mopeds and other small bikes and the larger, more powerful vehicles. In Canada and some U.S. jurisdictions, three-wheeled motor vehicles fall under the auspices of motorcycle regulations.

In some jurisdictions, the term "motorcycle" includes trikes

In the United Kingdom, the rules on which motorcycle may be ridden by whom are complex.[30] A "moped", which can be ridden at age 16, has a maximum design speed not exceeding 50 km/h (31 mph) and engine capacity no greater than 50 cc. A "light motorcycle", which can be ridden from age 17, has an engine up to 125 cc with a power output not exceeding 11 kW (15 hp). Only a Compulsory Basic Training (CBT) licence is needed to ride a learner motorcycle with an L plate. A "large restricted motorcycle" has a power output of not more than 25 kW (34 hp). Riders are restricted to riding large restricted motorcycles or smaller for two years after passing their initial motorcycle test. A "large motorcycle" has a power output of at least 25 kW.

For riders over age 21 there is a direct access route to gaining a licence to ride a large motorcycle, which allows somebody with no motorcycle experience to train and pass a test in around five days. All motorcycle riders in the UK must first take a one-day CBT course, regardless of which class of motorcycle they intend to ride. In addition a theory test must be taken prior to taking a practical test for any type of motorcycle licence.

A scooter and a motorcycle

In the United States, licencing requirements vary widely among the states and territories, but generally riders are required to pass written and practical (on-cycle) competency tests. In about half the states, successful completion of a rider education course (such as those offered by the Motorcycle Safety Foundation) is accepted by state licencing agencies in lieu of examination.

In New Zealand, "learner" and "restricted" motorcycles may only have a 250 cc engine capacity. This distinction draws some criticism, as it allows 15-year-old learner riders to operate bikes capable of reaching speeds in excess of 250 km/h (160 mph).

The legal age to be eligible to apply for a New Zealand motorcycle licence is 15 years and over. New Zealand employs a three stage system for motor vehicle licensing. At age 15, an individual can gain their first licence known as their "learner licence". They must hold this for at least 6 months before they are able to move on to their "restricted licence". They must then hold this "restricted licence" for one and half years. After a period of 6 to 18 months, depending on age and additional training, a holder of a restricted licence may sit the third and final stage known as the "full licence". Until an individual has their "full licence" they are only able to ride a motorcycle which has an engine capacity of 250 cc or less.[31]

A similar system is used in most states of Australia, with some variations. "Learners Permit" and "Provisional" license holders must not have bikes that exceed a power to weight ratio of 150kW/tonne or 660cc, whichever comes first. All 250cc bikes (with a few listed exceptions) are automatically included in this LAMS (Learner Approved Motorcycle Scheme) list.

Before getting a "Learners Permit" a Pre-Learner course is required, which issues a certificate of completion, valid for 3 months. Upon passing a computer test, the rider is granted a Learners Permit, which is valid for 12 months. Whilst on a learners permit, the rider may not carry a pillion or side car and may not exceed 80 kilometres per hour (50 mph) or the posted speed limit, whichever is lower.[32]

To progress to a Provisional License, the rider must successfully complete a Pre-Provisional riders course, followed by a riding skills test called MOST (Motorcycle Operator Skill Test). The rider is then able to obtain a "Provisional License". Provisional licenses can be renewed and must be held without suspension for 12 months, after which time it can be upgraded to a full license.[32]

The laws of some countries allow anyone with a car licence to legally ride mopeds not exceeding 50 cc in capacity, meaning that they do not need to show any competency in handling such a vehicle.

The laws and regulations for legal moped usage in the U.S. vary by state.[33] The specifics of the motorcycle and moped laws in the U.S. can be obtained from each individual state's Department of Motor Vehicles' websites.[34]

Environmental impact

In 2007 and 2008, motorcycles and scooters, due to good fuel efficiency, attracted interest in the United States from environmentalists and those affected by increased fuel prices.[35][36] Piaggio Group Americas supported this interest with the launch of a "Vespanomics" website and platform, citing lower per-mile carbon emissions (40 lb/mile less than the average car) and better fuel economy.[37]

Other sources, however, point out that while motorcycles may be better in terms of greenhouse gases, a motorcycle releases 10–20 times more total pollution per mile than a new car.[35][38] This pollution comes in large part from nitrogen oxide, a byproduct of combustion that is a major component of smog and is largely because of their less efficient catalytic converters.[35]

United States Environmental Protection Agency 2007 certification result reports for all vehicles versus on highway motorcycles (which also includes scooters),[39] the average certified emissions level for 12,327 vehicles tested was 0.734. The average "Nox+Co End-Of-Useful-Life-Emissions" for 3,863 motorcycles tested was 0.8531, for a difference of about 16%, not the claimed 10X factor. Likewise, if one looks at how many of the 2007 motorcycles tested were also catalytic equipped, 54% of them, 2,092, were equipped with a catalytic converter.

European emission standards for motorcycles are similar to those for cars. Motorcycles must meet Euro III standards,[40] while cars must meet Euro IV standards. Therefore, the difference in total pollution between motorcycles and cars that pass European emission standards would be small, certainly much smaller than the 10X factor claimed by the referenced LA Times article.

See also

References

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  3. Willoughby, Vic (1982). Exotic Motorcycles. London: Osprey Publishing, Ltd. ISBN 0850453224. 
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  6. "Hero Honda splendor sells more then 8.5 million units". indiacar.net. Retrieved on 2008-08-10.
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  13. "Soaring Gas Prices Shine Money-Saving Spotlight on Motorcycles". Reuters (19 May 2008). Retrieved on 2008-10-22.
  14. "About BACA". Bikers Against Child Abuse. Retrieved on 2007-10-10.
  15. "About MAG". MAG UK. Retrieved on 2007-10-10.
  16. Some other lobbying organisations are listed in Category:Motorcyclists organizations.
  17. Bob Tomlins (September 1997). "Rider training in Europe The Views and the Needs of the Rider" (PDF). The Federation of European Motorcyclists. Retrieved on 2007-06-30.
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  20. Motorcycle parking in Wellington CBD [Archive] - Kiwi Biker forums
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  27. "MMIC Information". Motorcycle and Moped Industry Council. Retrieved on 2007-05-16.
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  30. "Getting your motorcycle license". Land Transport New Zealand. Retrieved on 2008-03-05.
  31. 32.0 32.1 "Motorcycle". Rta.nsw.gov.au. Retrieved on 2008-10-24.
  32. "Moped Laws". www.mopedarmy.com. Retrieved on 2007-05-16.
  33. "DMV Websites". www.mopedarmy.com. Retrieved on 2007-05-16.
  34. 35.0 35.1 35.2 Susan Carpenter (June 11, 2008). "Motorcycles and emissions: The surprising facts", LA Times. Retrieved on 2008-08-08. 
  35. Judy Dahl (September 2007). "Baby, You Can Drive My Vespa", Madison Magazine. Retrieved on 2008-08-08. 
  36. "Vespanomics - Vespa Economics". Piaggio Group USA. Retrieved on 2008-08-08.
  37. Umbra Fisk (28 May 2003). "On motorcycles - Ask Umbra". Grist.
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  39. "Motorcycle Emissions Regs Examined". Motorcycle USA.

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