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106-406: The BSA Gold Star is a motorcycle made by BSA from 1938 to 1963. They were 350 cc and 500 cc single-cylinder four-stroke production motorcycles known for being among the fastest bikes of the 1950s. Being hand-built and with many optional performance modifications available, each motorcycle came from the factory with documented dynamometer test results, allowing the new owner to see

212-418: 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

318-588: 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

424-467: A waterwheel fed by a mill race powering via a gear train two frame saws which cut blocks by the way of some kind of connecting rods and cranks. The crank and connecting rod mechanisms of the other two archaeologically attested sawmills worked without a gear train. A Roman iron crank dating to the 2nd century AD was excavated in Augusta Raurica , Switzerland . The crank-operated Roman mill

530-482: A 5 bolt head, quite soon changed to 8 bolts, a stronger crankshaft, an even shorter connecting rod at 6 + 15 ⁄ 32  in (164 mm), oval flywheels (500), improved valve gear with eccentric adjustment, and an Amal GP carburettor. Power outputs were once again increased to around 30 and 38 bhp (22 and 28 kW) respectively. The DB Gold Star had an improved oil feed to the crankshaft and finned front brakes. DB32 models had smaller exhaust valves than

636-412: A Dutch farmer and windmill owner by the name Cornelis Corneliszoon van Uitgeest in 1592. His wind-powered sawmill used a crankshaft to convert a windmill's circular motion into a back-and-forward motion powering the saw. Corneliszoon was granted a patent for his crankshaft in 1597. From the 16th century onwards, evidence of cranks and connecting rods integrated into machine design becomes abundant in

742-475: A bar of high quality vacuum remelted steel . Though the fiber flow (local inhomogeneities of the material's chemical composition generated during casting) does not follow the shape of the crankshaft (which is undesirable), this is usually not a problem since higher quality steels, which normally are difficult to forge, can be used. Per unit, these crankshafts tend to be expensive due to the large amount of material that must be removed with lathes and milling machines,

848-640: A crank as a part of its mechanism. The crank was used to manually introduce dates. Evidence for the crank combined with a connecting rod, appears in the Ancient Greek Hierapolis mill , dating to the 3rd century AD under the Roman Empire; they are also found in stone sawmills in Roman Syria and Ephesus , Greek Ionia under Rome, dating to the 6th century. The pediment of the Hierapolis mill shows

954-512: A crankshaft, five centuries before the earliest known European description of a crankshaft. However, the automatic crank mechanism described by the Banū Mūsā would not have allowed a full rotation, but only a small modification was required to convert it to a crankshaft. In the Artuqid Sultanate , Arab engineer Ismail al-Jazari (1136–1206) described a crank and connecting rod system in

1060-789: 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

1166-430: A late antique original. Cranks used to turn wheels are also depicted or described in various works dating from the tenth to thirteenth centuries. The first depictions of the compound crank in the carpenter's brace appear between 1420 and 1430 in northern European artwork. The rapid adoption of the compound crank can be traced in the works of an unknown German engineer writing on the state of military technology during

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1272-573: A long-stroke engine was a lower rev limit and increased vibration at high RPM, due to the increased piston velocity. When designing an engine, the crankshaft configuration is closely related to the engine's firing order . Most production V8 engines (such as the Ford Modular engine and the General Motors LS engine ) use a cross-plane crank whereby the crank throws are spaced 90 degrees apart. However, some high-performance V8 engines (such as

1378-468: A main bearing between every cylinder and at both ends of the crankshaft, due to the high forces of combustion present. Flexing of the crankshaft was a factor in V8 engines replacing straight-eight engines in the 1950s; the long crankshafts of the latter suffered from an unacceptable amount of flex when engine designers began using higher compression ratios and higher engine speeds (RPM). The distance between

1484-420: A more accurate and cleaner finish. In 1953, a swingarm duplex (twin front downtube) frame was introduced, although rigid and plunger frames were still available, along with a much-improved gearbox for the new frames, with a choice of gear ratios These frames and all later GS and pre-unit B series swingarm frames had a distinctive kink in the lower offside rail, to accommodate and protect the oil-pump casting on

1590-654: 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

1696-414: 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

1802-551: A notable design of its era. In 1937, Wal Handley lapped the Brooklands circuit at over 100 mph (160 km/h) on a BSA Empire Star and was awarded one of the traditional Gold Star badges. That inspired BSA to produce the BSA Gold Star. The first Gold Star was an M24 model. It had an all-alloy 82 mm × 94 mm (3.2 in × 3.7 in) bore and stroke, 496 cc (30.3 cu in) displacement , with

1908-402: 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

2014-498: A rotating machine for two of his water-raising machines, which include both crank and shaft mechanisms. The Italian physician Guido da Vigevano ( c.  1280  – c.  1349 ), planning for a new Crusade , made illustrations for a paddle boat and war carriages that were propelled by manually turned compound cranks and gear wheels, identified as an early crankshaft prototype by Lynn Townsend White . Crankshafts were described by Leonardo da Vinci (1452–1519) and

2120-452: A second. Amongst the options available were a tachometer and a 190mm full-width front brake that gave a larger lining area than the standard 8" single-sided unit. A scrambles version was also offered. Many of the machines were exported to the USA where there was high demand for them. A series of special models were made for this lucrative market. Production ended in 1963. In 1954, BSA wanted to win

2226-477: A separate rocker box, bolted to the aluminium head, pushrod valve actuation, an Elektron (magnesium alloy) gearbox with close ratio option, and a rigid frame and girder forks made of Reynolds 531 light tubes devoid of sidecar attachment lugs. This model continued up to the start of World War II. There were two variants of the M24; 1938, JM24 and 1939, KM24. Both had a capacity of 496cc Several modifications were made to

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2332-545: A single power source by one connecting-rod, an idea also taken up by his compatriot Italian painter Francesco di Giorgio . The crank had become common in Europe by the early 15th century, as seen in the works of the military engineer Konrad Kyeser (1366–after 1405). Devices depicted in Kyeser's Bellifortis include cranked windlasses for spanning siege crossbows, cranked chain of buckets for water-lifting and cranks fitted to

2438-540: A small modification would have been required to convert it to a crankshaft. Al-Jazari (1136–1206) described a crank and connecting rod system in a rotating machine in two of his water-raising machines. His twin-cylinder pump incorporated a crankshaft. A crank is later also described in an early 15th century Arabic manuscript of Hero of Alexandria 's Mechanics . The first rotary hand mills, or rotary querns, appeared in Spain (600 BC – 500 BC), before they spread to

2544-660: A standard B-type rigid option for trial competition use. In 1950 both received larger 8" front brakes . In late 1951 the 500 gained a new barrel and Bert Hopwood design head with a separate rocker box, and the 350 had a new barrel and head of that design the following year The earlier 7 + 3 ⁄ 8  in (190 mm) connecting rod was shortened by 1 ⁄ 2  in (13 mm), which with other improvements gave an increase in power beneficial for performance. This engine redesign initially used sand-cast heads and barrels, still designated as ZB. After engine number ZB32GS-6001 production moved to die castings which allowed

2650-406: A very small number of YB32 competition engines may have had aluminum ZB32-type barrels and heads. These would have been "works" prototype bikes rather than true production Gold Stars. In BSA's model numbering system, Y denotes the year and B the range, followed by the engine number; YB is 1948, ZB is 1949, and so on, except that some models were available for more than one year so the number remained

2756-491: A wheel of bells. Kyeser also equipped the Archimedes' screws for water-raising with a crank handle, an innovation which subsequently replaced the ancient practice of working the pipe by treading. Pisanello painted a piston-pump driven by a water-wheel and operated by two simple cranks and two connecting-rods. The 15th century also saw the introduction of cranked rack-and-pinion devices, called cranequins, which were fitted to

2862-488: 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

2968-418: Is able to rotate in the engine block due to the 'main bearings '. Since the crankshaft is subject to large horizontal and torsional forces from each cylinder, these main bearings are located at various points along the crankshaft, rather than just one at each end. The number of main bearings is determined based on the overall load factor and the maximum engine speed. Crankshafts in diesel engines often use

3074-439: 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

3180-511: Is dated to the late 2nd century. Water-powered marble saws in Germany were mentioned by the late 4th century poet Ausonius ; about the same time, these mill types seem also to be indicated by Greek Saint Gregory of Nyssa from Anatolia . A rotary grindstone operated by a crank handle is shown in the Carolingian manuscript Utrecht Psalter ; the pen drawing of around 830 goes back to

3286-593: 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

BSA Gold Star - Misplaced Pages Continue

3392-610: 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

3498-493: 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

3604-477: 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

3710-447: Is sometimes used in V6 and V8 engines , in order to maintain an even firing interval while using different V angles, and to reduce the number of main bearings required. The downside of flying arms is that the rigidity of the crankshaft is reduced, which can cause problems at high RPM or high power outputs. In most engines, each connecting rod is attached a single crankshaft, which results in

3816-483: 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

3922-585: 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

4028-644: 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

4134-482: 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,

4240-705: 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

4346-478: 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

BSA Gold Star - Misplaced Pages Continue

4452-456: The Ferrari 488 ) instead use a flat-plane crank , whereby the throws are spaced 180° apart, which essentially results in two inline-four engines sharing a common crankcase. Flat-plane engines are usually able to operate at higher RPM, however they have higher second-order vibrations, so they are better suited to racing car engines. For some engines it is necessary to provide counterweights for

4558-500: 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

4664-399: The crossbow 's stock as a means of exerting even more force while spanning the missile weapon. In the textile industry, cranked reels for winding skeins of yarn were introduced. The Luttrell Psalter , dating to around 1340, describes a grindstone which was rotated by two cranks, one at each end of its axle; the geared hand-mill, operated either with one or two cranks, appeared later in

4770-400: The horsepower (bhp) produced. The Gold Star was almost continuously developed over its lifetime by BSA's engineers and riders, who improved its capabilities and increased output from its essentially simple push-rod petrol engine than had been thought possible. It was highly successful across almost all areas of motorcycle sport for well over a decade and is widely regarded by enthusiasts as

4876-488: The "Trackmaster" were also produced by American makers specifically for this purpose. A swinging arm version, known by the factory as "USA Short Circuit" was also produced in 1956 and 1957. In 1956, Chuck Minert won the Catalina Grand Prix on a modified Gold Star. (The Catalina Grand Prix was a popular 100-mile race on the island of Santa Catalina off the coast of Los Angeles . In 1956 more than 1,000 bikes started

4982-401: The "big end" of the connecting rods. Most modern crankshafts are located in the engine block . They are made from steel or cast iron , using either a forging , casting or machining process. The crankshaft is located within the engine block and held in place via main bearings which allow the crankshaft to rotate within the block. The up-down motion of each piston is transferred to

5088-548: The 15th century. Around 1480, the early medieval rotary grindstone was improved with a treadle and crank mechanism. Cranks mounted on push-carts first appear in a German engraving of 1589. In 9th century Abbasid Baghdad , automatically operated cranks appear in several of the hydraulic devices described by the Banū Mūsā brothers in the Book of Ingenious Devices . These automatically operated cranks appear in several devices, two of which contain an action which approximates to that of

5194-496: 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

5300-469: The 1949 model season, and to attract sporting buyers, the 71 mm × 88 mm (2.8 in × 3.5 in) bore and stroke, all alloy 348 cc ZB32 type Gold Star was first shown at the Earls Court motorcycle show at the end of 1948, with an extensive list of optional components. Unlike the pre-war M24 engine, the cylinder head was a strong one-piece casting, with the rockers incorporated into

5406-798: The 250 cc BSA C15 was developed (via the B40) into the 500 cc B50 . Although the B50 never attained the kudos of the DBD34, a B50 fielded by Mead & Tomkinson once held the class lap record in the Production TT , as well as gaining a class 2nd at the 24-hour endurance races in the Le Mans Bol d'Or and a class win at the Montjuïc circuit in Barcelona . CCM used BSA B50 bottom ends in their early specials. In 2021,

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5512-500: The CB32 and power increased slightly to over 30 bhp (22 kW). Power outputs of the 499 cc engines were developed to about 42 bhp (31 kW) over the next few years. The Clubman cam and timing option included a special silencer. At the end of this year, the BB and CB models were discontinued. The last batch of 350 cc DB32 machines left the factory in 1963. The 500 cc DBD34

5618-455: The East. The handle near the outer edge of the rotary part being the crank and human arm powering the rotation would be the connecting rod. However according to F. Lisheng and T. Qingjun, the hand-crank of the rotary quern was different from a crank, which was the combination of a hand-crank and a push-and-pull connecting rod by a hinge. The Antikythera mechanism, dated to around 200 BC, used

5724-466: 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

5830-520: The Hussite Wars: first, the connecting-rod, applied to cranks, reappeared; second, double-compound cranks also began to be equipped with connecting-rods; and third, the flywheel was employed for these cranks to get them over the 'dead-spot'. The concept was much improved by the Italian engineer and writer Roberto Valturio in 1463, who devised a boat with five sets, where the parallel cranks are all joined to

5936-521: 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

6042-655: The Mahindra Group, the new owners of the BSA marque, announced the production of a new BSA Gold Star. The first units were shipped to the UK from their manufacturing base in India in October 2022 and are expected to go on sale shortly thereafter through UK dealers. BSA Gold Stars won the following Isle of Man TT races. Motorcycle A motorcycle ( motorbike , bike , or, if three-wheeled,

6148-536: 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 ,

6254-432: The angle of the connecting rod varying as the piston moves through its stroke. This variation in angle pushes the pistons against the cylinder wall, which causes friction between the piston and cylinder wall. To prevent this, some early engines – such as the 1900–1904 Lanchester Engine Company flat-twin engines – connected each piston to two crankshafts that are rotating in opposite directions. This arrangement cancels out

6360-417: 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

6466-403: 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

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6572-560: 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

6678-408: The axis of the crankpins and the axis of the crankshaft determines the stroke length of the engine. Most modern car engines are classified as "over square" or short-stroke, wherein the stroke is less than the diameter of the cylinder bore . A common way to increase the low-RPM torque of an engine is to increase the stroke, sometimes known as "stroking" the engine. Historically, the trade-off for

6784-524: The bike was assembled by hand, and the engine bench tested and not released unless an acceptable power output was achieved, which was around 25 bhp (19 kW), depending on specification. They were 20 lb (9.1 kg) lighter than the comparable 17 bhp (13 kW) cast-iron barrel and head B series single. They were almost immediately successful, winning the Manx Grand Prix Clubmans 350 class from 1949 and remained so until 1956 when

6890-407: The class was discontinued. They could be specified in tourer, trials , ISDT , scrambles , racing or Clubman trim. Racing models used the well-established Amal TT carburettor. The rest of the 1948 BSA OHV B range "YB" models in the standard and competition forms had heavy but reliable cast iron heads and barrels. BSA reportedly experimented with new prototype components. It has been suggested that

6996-477: The crank, combined with a connecting rod in a machine, appears in the Ancient Greek Hierapolis sawmill in Roman Asia from the 3rd century AD and two stone sawmills at Gerasa , Roman Syria , and Ephesus , Greek Ionia under Rome, (both 6th century AD). On the pediment of the Hierapolis mill, a waterwheel fed by a mill race is shown powering via a gear train two frame saws which cut rectangular blocks by

7102-408: The crankshaft via connecting rods . A flywheel is often attached to one end of the crankshaft, in order to smoothen the power delivery and reduce vibration. A crankshaft is subjected to enormous stresses, in some cases more than 8.6 tonnes (19,000 pounds) per cylinder. Crankshafts for single-cylinder engines are usually a simpler design than for engines with multiple cylinders. The crankshaft

7208-486: The design during its lifespan. The 1939 KM model used a redesigned crank and crankcase with timing gears on fixed shafts, supported by a strong steel "outrigger" plate (a feature carried on throughout the Gold Star's entire production period.) The earlier JM model had cams that ran directly in the timing cover, with the potential for premature wear, hence the re-design. Power outputs were around 30bhp. The cast Elektron gearbox

7314-514: 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

7420-474: 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

7526-429: 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

7632-515: 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'

7738-489: The geometry of the motorcycle itself. These factors create a set of three basic postures. Factors of a motorcycle's ergonomic geometry that determine the seating posture include the height, angle and location of footpegs, seat and handlebars. Factors in a rider's physical geometry that contribute to seating posture include torso, arm, thigh and leg length, and overall rider height. Crankshaft The crankpins are also called rod bearing journals , and they rotate within

7844-513: The high material cost, and the additional heat treatment required. However, since no expensive tooling is needed, this production method allows small production runs without high up-front costs. The earliest hand-operated cranks appeared in China during the Han dynasty (202 BC – 220 AD). They were used for silk-reeling, hemp-spinning, for the agricultural winnowing fan, in the water-powered flour-sifter, for hydraulic-powered metallurgic bellows , and in

7950-531: The inter-conversion or rotary and reciprocating motion for other applications such as flour-sifting, treadle spinning wheels, water-powered furnace bellows, and silk-reeling machines. Ancient Egyptians had manual drills resembling a crank at the time of the Old Kingdom (2686–2181 BCE) and even a hieroglyph for the tool. However the Ancient Egyptian drill did not operate as a true crank. Later evidence for

8056-580: The lateral forces and reduces the requirement for counterweights. This design is rarely used, however a similar principle applies to balance shafts , which are occasionally used. Crankshafts can be created from a steel bar using roll forging . Today, manufacturers tend to favour the use of forged crankshafts due to their lighter weight, more compact dimensions and better inherent damping. With forged crankshafts, vanadium micro-alloyed steels are mainly used as these steels can be air-cooled after reaching high strengths without additional heat treatment, except for

8162-412: The lower timing-side crankcase. A small number of the early swingarm frames had a separate cast steel kink welded or brazed in place. Some modifications were also made to the general design so later frames are somewhat different from the BB type. In all later frames the frame rail was pressed out to form the kink. Some machines specified for lighter-weight competition use had no rear loops that normally held

8268-449: The magneto used in the B series, and that line of singles was ended. The demise of the Lucas magneto was a prime reason that BSA and Triumph reconfigured their pre-unit-construction parallel twins into engines with integral gearboxes, simultaneously converting the ignition system from magneto to battery and coil. The Gold Star was not considered for progression to unit construction, and instead,

8374-555: 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

8480-408: 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

8586-456: The physical similarities and use of some of the same parts. In 1949 the B32 Gold Star was in full production. The 499 cc B34 Gold Star was introduced, with a modified heavier crankshaft , stronger drive side crankcase, larger diameter drive-side main shaft, and a different design main bearing. The 350 cc continued as before. Spring plunger frames were most commonly used, along with

8692-488: The pillion footrests. Due to the new frame a new larger and more distinctive chrome plated fuel tank was introduced. The engines maintained the same die-cast barrel and head with a separate rocker box design as with the late ZB models. The BB models remained in production for touring and trial competition use into 1954. The new CB engine was introduced, (subsequently known as the Big Fin engine), given deeper and squarer finning,

8798-425: The prestigious United States Daytona 200 race. During the 1950s, the race was run partly on asphalt and partly on the beach at Daytona . A team of workers prepared Gold Stars and A7 Shooting Stars were entered. The race was won by a Shooting Star with a Gold Star in 3rd place. A replica of the work Gold Star was offered to the public. The specification included a rigid frame, which saved 50 lb (23 kg) over

8904-416: The race.) Modifications included a larger fuel tank, an air scoop on the front brake and a 19" front wheel. US West Coast BSA distributor, Hap Alzina, persuaded the factory to produce a replica named after the race. The Gold Star Catalina was manufactured from 1959 to 1963. Towards the end of its production life, the Gold Star was offered only in scrambles or Clubman trim. In 1963 Lucas ceased to produce

9010-579: 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

9116-399: The reciprocating mass of the piston, conrods and crankshaft, in order to improve the engine balance . These counterweights are typically cast as part of the crankshaft but, occasionally, are bolt-on pieces. In some engines, the crankshaft contains direct links between adjacent crankpins , without the usual intermediate main bearing. These links are called flying arms . This arrangement

9222-400: 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

9328-491: The same over that time. All genuine bench-tested Gold Stars had the addition of "GS" after the year and range letters; thus ZB32GS, followed by the actual engine number. A standard YB32 or subsequent years competition machine was not a Gold Star as it did not have a bench-tested engine or the full "GS" engine number. In subsequent years BSA produced competition machines delineated with a stamped "A" to signify an aluminium engine. They were not bench-tested Gold Star engines, despite

9434-466: 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

9540-621: 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

9646-449: The surface hardening of the bearing surfaces. The low alloy content also makes the material cheaper than high-alloy steels. Carbon steels also require additional heat treatment to reach the desired properties. Another construction method is to cast the crankshaft from ductile iron. Cast iron crankshafts are today mostly found in cheaper production engines where the loads are lower. Crankshafts can also be machined from billet , often

9752-471: 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

9858-433: The swinging-arm frame. Engine modifications included using a 350cc head, which had a better downdraught angle, machined to 500cc dimensions and fitted with a large inlet valve. The engine produced 44bhp. The model was also offered in subsequent years. Rigid framed machines became successful on the USA "Flat Track" scene in the hands of riders such as Dick Mann and tuners like CR Axtell. Special lightweight rigid frames such as

9964-547: The technological treatises of the period: Agostino Ramelli 's The Diverse and Artifactitious Machines of 1588 depicts eighteen examples, a number that rises in the Theatrum Machinarum Novum by Georg Andreas Böckler to 45 different machines. Cranks were formerly common on some machines in the early 20th century; for example almost all phonographs before the 1930s were powered by clockwork motors wound with cranks. Reciprocating piston engines use cranks to convert

10070-474: The unit. The all-new spring frame had so-called plunger suspension, halfway between the earlier rigid and later swingarm types. These used undamped springs mounted on shafts and forgings on either side of the rear wheel spindle and although they offered more comfort for regular road riding compared to rigid frames, they came in time to be regarded by competition riders and racers as often criticized by competition riders as heavy and difficult to handle. Once ordered

10176-462: 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

10282-449: 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

10388-557: The way of some kind of connecting rods and, through mechanical necessity, cranks. The accompanying inscription is in Greek . The crank and connecting rod mechanisms of the other two archaeologically attested sawmills worked without a gear train. The crank appears in the mid-9th century in several of the hydraulic devices described by the Banū Mūsā brothers in their Book of Ingenious Devices . These devices, however, made only partial rotations and could not transmit much power, although only

10494-528: The well windlass . Pottery models with crank operated winnowing fans were unearthed dating back to the Western Han dynasty (202 BC - 9 AD). The rotary winnowing fan greatly increased the efficiency of separating grain from husks and stalks. The Chinese used the crank-and-connecting rod in ancient blasting apparatus, textile machinery and agricultural machinery no later than the Western Han dynasty (202 BC – 9 AD). Eventually crank-and-connecting rods were used in

10600-481: 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

10706-803: 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

10812-509: Was dropped in 1939 to use the side-valve M20 's cast aluminum shell but with close gear ratios as an option. Some KM's were used by the military at the start of WW2. 266 JM24 models were produced and 298 KM24, of which 120 were sent to destinations outside the UK. There are over 100 recorded survivors on the bsa-m24.com website After the war, in 1945–46, BSA introduced the iron engine 348 cc (21.2 cu in) B31 and subsequent 499 cc (30.5 cu in) B33 . In preparation for

10918-492: Was introduced in 1956, with clip-on handlebars, the same big finned alloy engine with a newly designed head, 38 mm ( 1 1/2" ) bell-mouth Amal carburettor and swept-back exhaust. The DBD34 had a 110 mph (180 km/h) top speed. The Gold Star dominated the Isle of Man Clubmans TT that year. Later models had an ultra close-ratio gearbox (RRT2) with a very high first gear, enabling 60 mph (97 km/h) before changing up to

11024-447: 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

11130-506: 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

11236-464: 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

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