Air-cooled engines rely on the circulation of air directly over heat dissipation fins or hot areas of the engine to cool them in order to keep the engine within operating temperatures. Air-cooled designs are far simpler than their liquid-cooled counterparts, which require a separate radiator , coolant reservoir, piping and pumps.
65-440: The Norton Mercury was a 646 cc (39.4 cu in) air-cooled OHV parallel twin motorcycle made by Norton-Villiers from 1968 to 1970. It was the last Norton model to use the 'featherbed' frame. Following the collapse of AMC and the subsequent formation of Norton Villiers, the company's focus had been on the new Norton Commando . There was a large inventory of parts from previous models that would not be used on
130-418: A manual five- or six-speed sequential transmission drives the swingarm -mounted rear wheel by a chain , driveshaft , or belt . The repair can be done using a Motorcycle lift . Motorcycle fuel economy varies greatly with engine displacement and riding style. A streamlined, fully faired Matzu Matsuzawa Honda XL125 achieved 470 mpg ‑US (0.50 L/100 km; 560 mpg ‑imp ) in
195-588: A trike ) is a two or three-wheeled motor vehicle steered by a handlebar from a saddle-style seat. Motorcycle designs vary greatly to suit a range of different purposes: long-distance travel, commuting , cruising , sport (including racing ), and off-road riding. Motorcycling is riding a motorcycle and being involved in other related social activities such as joining a motorcycle club and attending motorcycle rallies . The 1885 Daimler Reitwagen made by Gottlieb Daimler and Wilhelm Maybach in Germany
260-412: A closed circuit carrying liquid coolant through channels in the engine block and cylinder head. A fluid in these channels absorbs heat and then flows to a heat exchanger or radiator where the coolant releases heat into the air (or raw water , in the case of marine engines ). Thus, while they are not ultimately cooled by the liquid, as the heat is exchanged with some other fluid like air, because of
325-430: A fluid is a function of its capacity and the difference in input and output temperatures. As the boiling point of water is reduced with lower pressure, and the water could not be efficiently pumped as steam, radiators had to have enough cooling power to account for the loss in cooling power as the aircraft climbed. The resulting radiators were quite large and caused a significant amount of aerodynamic drag . This placed
390-789: A full motorcycle licence or endorsement for completing a Motorcycle Safety course varies by province. Without the Motorcycle Safety Course the chance of getting insurance for the motorcycle is very low. 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. Training course graduates may qualify for reduced insurance premiums. Motorcyclists and motor scooter riders are also exposed to an increased risk of suffering hearing damage such as hearing loss and tinnitus (ringing ears). The noise
455-486: A great percentage of the heat generated, around 44%, escapes through the exhaust. Another 8% or so ends up in the oil , which itself has to be cooled in an oil cooler . This means less than half of the heat has to be removed through other systems. In an air-cooled engine, only about 12% of the heat flows out through the metal fins. Air cooled engines usually run noisier, however it provides more simplicity which gives benefits when it comes to servicing and part replacement and
520-440: A horizontal fashion as a Flat engine , while vertical Straight-four engine have been used. Examples of past air-cooled road vehicles, in roughly chronological order, include: During the 1920s and 30s there was a great debate in the aviation industry about the merits of air-cooled vs. liquid-cooled designs. At the beginning of this period, the liquid used for cooling was water at ambient pressure. The amount of heat carried away by
585-654: A motorcycle ( German : Motorrad ). Excelsior Motor Company , originally a bicycle manufacturing company based in Coventry , England , began production of their first motorcycle model in 1896. The first production motorcycle in the US was the Orient-Aster, built by Charles Metz in 1898 at his factory in Waltham, Massachusetts . In the early period of motorcycle history, many producers of bicycles adapted their designs to accommodate
650-414: A motorcycle either as OEM (factory-fitted) or aftermarket . Such accessories are selected by the owner to enhance the motorcycle's appearance, safety, performance, or comfort, and may include anything from mobile electronics to sidecars and trailers . Motorcycles have a higher rate of fatal accidents than automobiles or trucks and buses. United States Department of Transportation data for 2005 from
715-402: A role in how a motorcycle performs in given conditions. For example, one with a longer wheelbase provides the feeling of more stability by responding less to disturbances. Motorcycle tyres have a large influence over handling. Motorcycles must be leaned in order to make turns. This lean is induced by the method known as countersteering , in which the rider momentarily steers the handlebars in
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#1732891052619780-488: Is 43.47 which is 28 times higher than for cars (37 times more deaths per mile travelled in 2007). Furthermore, for motorcycles the accident rates have increased significantly since the end of the 1990s, while the rates have dropped for passenger cars. The most common configuration of motorcycle accidents in the United States is when a motorist pulls out or turns in front of a motorcyclist, violating their right-of-way. This
845-439: Is caused by wind noise while riding, rolling noise from the tyres and the engine itself. The helmet only provides insufficient protection against high sound pressure levels. Medicine (as of 2024) is not able to cure hearing damage. Wearing hearing protection, such as special earplugs for motorcyclists, can help prevent hearing damage. The motorcyclist's riding position depends on rider body-geometry ( anthropometry ) combined with
910-593: Is increasingly problematic. The first (petroleum fueled) internal-combustion motorcycles, like the German Reitwagen , were, however, also the first practical motorcycles. If a two-wheeled vehicle with steam propulsion is considered a motorcycle, then the first motorcycles built seem to be the French Michaux-Perreaux steam velocipede which patent application was filed in December 1868, constructed around
975-610: Is necessary to pass the basic motorcycle licence 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 may benefit from reduced insurance costs In South Africa, the Think Bike campaign is dedicated to increasing both motorcycle safety and
1040-493: Is often a racing counterpart to each type, such as road racing and street bikes, or motocross including dirt bikes. Street bikes include cruisers , sportbikes , scooters and mopeds , and many other types. Off-road motorcycles include many types designed for dirt-oriented racing classes such as motocross and are not street legal in most areas. Dual purpose machines like the dual-sport style are made to go off-road but include features to make them legal and comfortable on
1105-477: Is sometimes called a SMIDSY , an acronym formed from the motorists' common response of "Sorry mate, I didn't see you". Motorcyclists can anticipate and avoid some of these crashes with proper training, increasing their visibility to other traffic, keeping to the speed limits, and not consuming alcohol or other drugs before riding. The United Kingdom has several organisations dedicated to improving motorcycle safety by providing advanced rider training beyond what
1170-483: Is the 1958 Honda Super Cub , which went on to become the biggest selling vehicle of all time, with its 60 millionth unit produced in April 2008. Today, this area is dominated by mostly Indian companies with Hero MotoCorp emerging as the world's largest manufacturer of two wheelers. Its Splendor model has sold more than 8.5 million to date. Other major producers are Bajaj and TVS Motors . Motorcycle construction
1235-585: Is the engineering, manufacturing, and assembly of components and systems for a motorcycle which results in the 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 . Some other body parts, designed for either aesthetic or performance reasons may be added. A petrol-powered engine typically consisting of between one and four cylinders (and less commonly, up to eight cylinders) coupled to
1300-477: Is the primary goal. Their simplicity makes them suited for uses in small applications like chainsaws and lawn mowers , as well as small generators and similar roles. These qualities also make them highly suitable for aviation use, where they are widely used in general aviation aircraft and as auxiliary power units on larger aircraft. Their simplicity, in particular, also makes them common on motorcycles . Most modern internal combustion engines are cooled by
1365-418: Is usually cheaper to be maintained. Many motorcycles use air cooling for the sake of reducing weight and complexity. Few current production automobiles have air-cooled engines (such as Tatra 815 ), but historically it was common for many high-volume vehicles. The orientation of the engine cylinders is commonly found in either single-cylinder or coupled in groups of two, and cylinders are commonly oriented in
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#17328910526191430-644: The Australian Capital Territory , Tasmania and the Northern Territory , it is compulsory to complete a basic rider training course before being issued a Learners Licence, after which they can ride on public roads. In Canada, motorcycle rider training is compulsory in Quebec and Manitoba only, but all provinces and territories have graduated licence programs which place restrictions on new drivers until they have gained experience. Eligibility for
1495-482: The Craig Vetter Fuel Economy Challenge "on real highways – in real conditions". Due to low engine displacements (100–200 cc (6.1–12.2 cu in)), and high power-to-mass ratios, motorcycles offer good fuel economy. Under conditions of fuel scarcity like 1950s Britain and modern developing nations, motorcycles claim large shares of the vehicle market. In the United States,
1560-705: The FIM in the light of the safety concerns. From the 1960s through the 1990s, small two-stroke motorcycles were popular worldwide, partly as a result of East German MZs Walter Kaaden's engine work in the 1950s. In the 21st century, the motorcycle industry is mainly dominated by Indian and Japanese motorcycle companies. In addition to the large capacity motorcycles, there is a large market in smaller capacity (less than 300 cc) motorcycles, mostly concentrated in Asian and African countries and produced in China and India. A Japanese example
1625-478: 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. The same data shows that 1.56 fatalities occur per 100 million vehicle miles travelled for passenger cars, whereas for motorcycles the figure
1690-500: The US Department of Transportation , the number of fatalities per vehicle mile traveled was 37 times higher for motorcycles than for cars. The term motorcycle has different legal definitions depending on jurisdiction (see § Legal definitions and restrictions ). There are three major types of motorcycle: street, off-road, and dual purpose. Within these types, there are many sub-types of motorcycles for different purposes. There
1755-655: The 1900s. The first commercial production was by the New Way Motor Company of Lansing, Michigan, US. The company produced air-cooled engines in single and twin cylinders in both horizontal and vertical cylinder format. Subsequent to their initial production which was exported worldwide, other companies took up the advantages of this cooling method, especially in small portable engines. Applications include mowers, generators, outboard motors, pump sets, saw benches and auxiliary power plants and more. Motorcycle A motorcycle ( motorbike , bike , or, if three-wheeled,
1820-496: The 1920s stood out. Initially, using converted a Woodmann-designed OHV Blackburne engine it became the first 350 cc to exceed 100 mph (160 km/h), recording 100.81 mph (162.24 km/h) over the flying kilometre during April 1924.[7] Later, Chater-Lea set a world record for the flying kilometre for 350 cc and 500 cc motorcycles at 102.9 mph (165.6 km/h) for the firm. Chater-Lea produced variants of these world-beating sports models and became popular among racers at
1885-743: The Commando, and to use up this stock the Mercury was conceived. The Mercury was introduced in October 1968 and around 750 machines were produced, most of the production going to the US. The model was also used by the Nigerian Police . The engine in the Mercury was based on that of the 650SS , which itself was a development of Bert Hopwood 's 1948 500 cc twin first used on the Model 7 Dominator . The pre-unit air-cooled OHV vertical twin engine used an alloy head that
1950-466: The First World War, motorbike production was greatly ramped up for the war effort to supply effective communications with front line troops. Messengers on horses were replaced with despatch riders on motorcycles carrying messages, performing reconnaissance and acting as a military police. American company Harley-Davidson was devoting over 50% of its factory output toward military contract by the end of
2015-521: The Isle of Man TT. Today, the firm is probably best remembered for its long-term contract to manufacture and supply AA Patrol motorcycles and sidecars. By the late 1920s or early 1930s, DKW in Germany took over as the largest manufacturer. In the 1950s, streamlining began to play an increasing part in the development of racing motorcycles and the "dustbin fairing" held out the possibility of radical changes to motorcycle design. NSU and Moto Guzzi were in
Norton Mercury - Misplaced Pages Continue
2080-677: The Light-Sport Aircraft ( LSA ) and ultralight aircraft market. Rotax uses a combination of air-cooled cylinders and liquid-cooled cylinder heads. Some small diesel engines, e.g. those made by Deutz AG and Lister Petter are air-cooled. Probably the only big Euro 5 truck air-cooled engine (V8 320 kW power 2100 N·m torque one) is being produced by Tatra . BOMAG part of the FAYAT group also utilizes an air cooled inline 6 cylinder motor, in many of their construction vehicles. Stationary or portable engines were commercially introduced early in
2145-492: The Mercury were based on the slimline featherbed frame and Roadholder forks . Unique for this model was a humped dualseat. Brakes were 8 in (200 mm) drum front and 7 in (180 mm) rear. Most of the production was finished with Atlantic blue oil tank, mudguards and chaincases with a silver petrol tank. It was also available in black with a silver or red tank. Air-cooled engine Air-cooled engines are widely seen in applications where weight or simplicity
2210-565: The Navy underwriting air-cooled engine development at Pratt & Whitney and Wright Aeronautical . Most other groups, especially in Europe where aircraft performance was rapidly improving, were more concerned with the issue of drag. While air-cooled designs were common on light aircraft and trainers, as well as some transport aircraft and bombers , liquid-cooled designs remained much more common for fighters and high-performance bombers. The drag issue
2275-581: The United States by organisations ranging from state agencies to non-profit organisations to corporations. Most states use the courses designed by the Motorcycle Safety Foundation (MSF), while Oregon and Idaho developed their own. All of the training programs include a Basic Rider Course, an Intermediate Rider Course and an Advanced Rider Course. In Ireland , since 2010, in the UK and some Australian jurisdictions, such as Victoria , New South Wales ,
2340-417: The art at the time. Starting was by compressed air. The engine was liquid-cooled, with a radiator over the rear driving wheel. Speed was controlled by means of a throttle valve lever. No braking system was fitted; the vehicle was stopped by raising and lowering the rear driving wheel using a foot-operated lever; the weight of the machine was then borne by two small castor wheels. The driver was seated between
2405-403: The average motorcycle fuel economy is 44 miles per US gallon (19 km per liter). Very high fuel economy equivalents are often derived by electric motorcycles. Electric motorcycles are nearly silent, zero-emission electric motor-driven vehicles. Operating range and top speed are limited by battery technology. Fuel cells and petroleum-electric hybrids are also under development to extend
2470-560: The awareness of motorcycles on the country's roads. The campaign, while strongest in the Gauteng province, has representation in Western Cape, KwaZulu Natal and the Free State. It has dozens of trained marshals available for various events such as cycle races and is deeply involved in numerous other projects such as the annual Motorcycle Toy Run. Motorcycle safety education is offered throughout
2535-514: The direction opposite of the desired turn. This practice is counterintuitive and therefore often confusing to novices – and even many experienced motorcyclists. With such short wheelbase , motorcycles can generate enough torque at the rear wheel, and enough stopping force at the front wheel, to lift the opposite wheel off the road. These actions, if performed on purpose, are known as wheelies and stoppies (or endos) respectively. Various features and accessories may be attached to
2600-474: The first "modern motorcycle". Introduced in 1915 it had a 550 cc side-valve four-stroke engine with a three-speed gearbox and belt transmission. It was so popular with its users that it was nicknamed the "Trusty Triumph". By 1920, Harley-Davidson was the largest manufacturer, with their motorcycles being sold by dealers in 67 countries. Amongst many British motorcycle manufacturers, Chater-Lea with its twin-cylinder models followed by its large singles in
2665-429: The five brands with enough data to draw conclusions, Honda, Kawasaki and Yamaha were statistically tied, with 11 to 14% of those bikes in the survey experiencing major repairs. Harley-Davidsons had a rate of 24%, while BMWs did worse, with 30% of those needing major repairs. There were not enough Triumph and Suzuki motorcycles surveyed for a statistically sound conclusion, though it appeared Suzukis were as reliable as
Norton Mercury - Misplaced Pages Continue
2730-515: The front wheels. It was not, however, a success, as Butler failed to find sufficient financial backing. Many authorities have excluded steam powered , electric motorcycles or diesel-powered two-wheelers from the definition of a 'motorcycle', and credit the Daimler Reitwagen as the world's first motorcycle. Given the rapid rise in use of electric motorcycles worldwide, defining only internal-combustion powered two-wheelers as 'motorcycles'
2795-568: The liquid-coolant circuit they are known as liquid-cooled . In contrast, heat generated by an air-cooled engine is released directly into the air. Typically this is facilitated with metal fins covering the outside of the Cylinder Head and cylinders which increase the surface area that air can act on. Air may be force fed with the use of a fan and shroud to achieve efficient cooling with high volumes of air or simply by natural air flow with well designed and angled fins. In all combustion engines,
2860-506: The much smaller radiators and less fluid in the system, the weight and drag of these designs was well below contemporary air-cooled designs. On a weight basis, these liquid-cooled designs offered as much as 30% better performance. In the late- and post-war era, the high-performance field quickly moved to jet engines . This took away the primary market for late-model liquid-cooled engines. Those roles that remained with piston power were mostly slower designs and civilian aircraft. In these roles,
2925-555: The new internal combustion engine. As the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle producers increased. Many of the nineteenth-century inventors who worked on early motorcycles often moved on to other inventions. Daimler and Roper, for example, both went on to develop automobiles. At the end of the 19th century the first major mass-production firms were set up. In 1898, Triumph Motorcycles in England began producing motorbikes, and by 1903 it
2990-408: The other three Japanese brands while Triumphs were comparable to Harley-Davidson and BMW. Three-fourths of the repairs in the survey cost less than US$ 200 and two-thirds of the motorcycles were repaired in less than two days. In spite of their relatively worse reliability in this survey, Harley-Davidson and BMW owners showed the greatest owner satisfaction, and three-fourths of them said they would buy
3055-481: The radiator size by 50% compared to water cooled designs. The experiments were extremely successful and by 1932 the company had switched all future designs to this coolant. At the time, Union Carbide held a monopoly on the industrial process to make glycol, so it was initially used only in the US, with Allison Engines picking it up soon after. It was not until the mid-1930s that Rolls-Royce adopted it as supplies improved, converting all of their engines to glycol. With
3120-579: The range and improve performance of the electric drive system. A 2013 survey of 4,424 readers of the US Consumer Reports magazine collected reliability data on 4,680 motorcycles purchased new from 2009 to 2012. The most common problem areas were accessories , brakes , electrical (including starters , charging , ignition ), and fuel systems , and the types of motorcycles with the greatest problems were touring, off-road/dual sport, sport-touring, and cruisers. There were not enough sport bikes in
3185-400: The same bike again, followed by 72% of Honda owners and 60 to 63% of Kawasaki and Yamaha owners. Two-wheeled motorcycles stay upright while rolling due to a physical property known as conservation of angular momentum in the wheels. Angular momentum points along the axle, and it "wants" to stay pointing in that direction. Different types of motorcycles have different dynamics and these play
3250-466: The same time as the American Roper steam velocipede , built by Sylvester H. Roper of Roxbury, Massachusetts , who had been demonstrating his machine at fairs and circuses in the eastern U.S. since 1867. Roper built about 10 steam cars and cycles from the 1860s until his death in 1896. In 1894, Hildebrand & Wolfmüller became the first series production motorcycle, and the first to be called
3315-454: The simplicity and reduction in servicing needs is far more important than drag, and from the end of the war on almost all piston aviation engines have been air-cooled, with few exceptions. As of 2020 , most of the engines manufactured by Lycoming and Continental are used by major manufacturers of light aircraft Cirrus , Cessna and so on. Other engine manufactures using air-cooled engine technology are ULPower and Jabiru , more active in
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#17328910526193380-458: The steam through tubes located just under the skin of the wings and fuselage, where the fast moving outside air condensed it back to water. While this concept was used on a number of record-setting aircraft in the late 1930s, it always proved impractical for production aircraft for a wide variety of reasons. In 1929, Curtiss began experiments replacing water with ethylene glycol in a Curtiss D-12 engine. Glycol could run up to 250 C and reduced
3445-621: The street as well. Each configuration offers either specialised advantage or broad capability, and each design creates a different riding posture. In some countries the use of pillions (rear seats) is restricted. The first internal combustion , petroleum fueled motorcycle was the Daimler Reitwagen . It was designed and built by the German inventors Gottlieb Daimler and Wilhelm Maybach in Bad Cannstatt , Germany, in 1885. This vehicle
3510-471: The survey for a statistically significant conclusion, though the data hinted at reliability as good as cruisers. These results may be partially explained by accessories including such equipment as fairings, luggage, and auxiliary lighting, which are frequently added to touring, adventure touring/dual sport and sport touring bikes. Trouble with fuel systems is often the result of improper winter storage, and brake problems may also be due to poor maintenance. Of
3575-454: The two designs roughly equal in terms of power to drag, but the air-cooled designs were almost always lighter and simpler. In 1921, the US Navy , largely due to the efforts of Commander Bruce G. Leighton , decided that the simplicity of the air-cooled design would result in less maintenance workload, which was paramount given the limited working area of aircraft carriers . Leighton's efforts led to
3640-462: The vanguard of this development, both producing very radical designs well ahead of their time. NSU produced the most advanced design, but after the deaths of four NSU riders in the 1954–1956 seasons, they abandoned further development and quit Grand Prix motorcycle racing . Moto Guzzi produced competitive race machines, and until the end of 1957 had a succession of victories. The following year, 1958, full enclosure fairings were banned from racing by
3705-578: The volume of water required and the size of the radiator by as much as 30%, which opened the way to a new generation of high-powered, relatively low-drag liquid cooled inline engines such as the Rolls-Royce Merlin and Daimler-Benz DB601 , which had an advantage over the unpressurized early versions of the Jumo 211 . This also led to development work attempting to eliminate the radiator entirely using evaporative cooling , allowing it to turn to steam and running
3770-449: The war. The British company Triumph Motorcycles sold more than 30,000 of its Triumph Type H model to allied forces during the war. With the rear wheel driven by a belt, the Model H was fitted with a 499 cc (30.5 cu in) air-cooled four-stroke single-cylinder engine. It was also the first Triumph without pedals . The Model H in particular, is regarded by many as having been
3835-481: Was a three-wheeled vehicle, with the rear wheel directly driven by a 5 ⁄ 8 hp (0.47 kW), 40 cc (2.4 cu in) displacement, 2 + 1 ⁄ 4 in × 5 in (57 mm × 127 mm) bore × stroke, flat twin four-stroke engine (with magneto ignition replaced by coil and battery) equipped with rotary valves and a float-fed carburettor (five years before Maybach ) and Ackermann steering , all of which were state of
3900-803: Was designed as an expedient testbed for their new engine, rather than a true prototype vehicle. The first commercial design for a self-propelled cycle was a three-wheel design called the Butler Petrol Cycle, conceived of Edward Butler in England in 1884. He exhibited his plans for the vehicle at the Stanley Cycle Show in London in 1884. The vehicle was built by the Merryweather Fire Engine company in Greenwich , in 1888. The Butler Petrol Cycle
3965-436: Was fed by a single Amal Concentric carburettor. A number of internal improvements introduced for the Commando engine were used in the Mercury's engine. Primary drive was by chain to a multiplate wet clutch and was enclosed in a pressed steel chaincase. The gearbox had 4 speeds. The machine used 12 volt electrics and was charged by a crankshaft mounted alternator . Ignition was by coil and points . The cycle parts of
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#17328910526194030-447: Was producing over 500 bikes. Other British firms were Royal Enfield , Norton , Douglas Motorcycles and Birmingham Small Arms Company who began motorbike production in 1899, 1902, 1907 and 1910, respectively. Indian began production in 1901 and Harley-Davidson was established two years later. By the outbreak of World War I, the largest motorcycle manufacturer in the world was Indian, producing over 20,000 bikes per year. During
4095-506: Was the first internal combustion, petroleum -fueled motorcycle. In 1894, Hildebrand & Wolfmüller became the first series production motorcycle. Globally, motorcycles are comparable numerically to cars as a method of transport: in 2021, approximately 58.6 million new motorcycles were sold around the world, while 66.7 million cars were sold over the same period. In 2022, the top four motorcycle producers by volume and type were Honda , Yamaha , Kawasaki , and Suzuki . According to
4160-464: Was unlike either the safety bicycles or the boneshaker bicycles of the era in that it had zero degrees of steering axis angle and no fork offset , and thus did not use the principles of bicycle and motorcycle dynamics developed nearly 70 years earlier. Instead, it relied on two outrigger wheels to remain upright while turning. The inventors called their invention the Reitwagen ("riding car"). It
4225-489: Was upset by the 1929 introduction of the NACA cowl , which greatly reduced the drag of air-cooled engines in spite of their larger frontal area, and the drag related to cooling was at this point largely even. In the late 1920s into the 1930s, a number of European companies introduced cooling system that kept the water under pressure allowed it to reach much higher temperatures without boiling, carrying away more heat and thus reducing
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