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72-673: In 1969 Honda revealed the CB750 superbike, establishing the template for the Universal Japanese Motorcycle with a range of transverse inline-fours . Relishing technological innovation, Honda unexpectedly moved on to adopt the V4 ("VF") configuration. However, some of the early VF models suffered mechanical problems, mainly as a result of poor quality camshafts (the "chocolate cams"). Honda, alarmed that they were losing their hard-won reputation for reliability, moved to introduce

144-814: A 'King of Motorcycles', and the CB750 appeared at the Tokyo Show in November 1968. In the UK, it was publicly launched at the Brighton motorcycle show, held at the Metropole Hotel exhibition centre during April 1969, with an earlier press-launch at Honda's London headquarters; the pre-production versions appeared with a high and very wide handlebar intended for the US market. The AMA Competition Committee recognised

216-456: A DOHC configuration gradually increased after World War II, beginning with sports cars. Iconic DOHC engines of this period include the 1948–1959 Lagonda straight-six engine , the 1949–1992 Jaguar XK straight-six engine and the 1954–1994 Alfa Romeo Twin Cam inline-four engine. The 1966-2000 Fiat Twin Cam inline-four engine was one of the first DOHC engines to use a toothed timing belt instead of

288-557: A flat engine. A V engine or flat engine requires four camshafts to function as a DOHC engine, since having two camshafts in total would result in only a single camshaft per cylinder bank for these engine layouts. Some V engines with four camshafts have been marketed as "quad-cam" engines, however technically "quad-cam" would require four camshafts per cylinder bank (i.e. eight camshafts in total), therefore these engines are merely dual overhead camshaft engines. Many DOHC engines have four valves per cylinder. The camshaft usually operates

360-608: A fully enclosed-drivetrain), the American Liberty L-12 V12 engine, which closely followed the later Mercedes D.IIIa design's partly-exposed SOHC valvetrain design; and the Max Friz -designed; German BMW IIIa straight-six engine. The DOHC Napier Lion W12 engine was built in Great Britain beginning in 1918. Most of these engines used a shaft to transfer drive from the crankshaft up to the camshaft at

432-465: A major departure from the established layout that previous CB750s possessed, namely in regards to its engine configuration and fuel injection system. The frame and engine of the motorcycle is lifted directly from new XL750 Transalp ; the new engine being a 755cc DOHC 8-valve liquid-cooled parallel twin with an output of 90.5 hp @ 9,500 rpm and 55.3 lb.-ft. @ 7,250 rpm. It is also the first CB750 to use Honda's PGM-FI fuel system. The CB750 Hornet

504-653: A new motorcycle, the Ariel Ace . Honda developed the RC30 as a homologation racing version which was used from 1988 to 1993. It was the first large capacity motorcycle to use a single-sided swingarm .. The RC30 was succeeded in 1994 by the RC45 . Honda CB750 The Honda CB750 is an air-cooled , transverse , in-line-four-cylinder -engine motorcycle made by Honda over several generations for year models 1969–2008 with an upright, or standard , riding posture. It

576-451: A single overhead camshaft (SOHC) and a front disc brake, neither of which had previously been available on an affordable mainstream production motorcycle. This spec, married with the introductory price of US$ 1,495 (US$ 12,421 in current money), gave the CB750 a considerable sporting-performance advantage over its competition, particularly its British rivals. Cycle magazine called the CB750, "the most sophisticated production bike ever" at

648-475: A single-sided swingarm , linked braking , ABS , and VTEC . The VFR1200 became the first motorcycle to feature a dual-clutch transmission . Not all of these innovations proved popular with riders, who often preferred the simple robustness of the earlier models. Honda also developed a limited edition VFR, the Honda RC30 , as a homologation racing platform. This motorcycle achieved some racing success, but

720-493: A tall-geared CR750 to victory preceded the June 1970 Isle of Man TT races when two 'official' Honda CB750s were entered, again ridden by Irishman Tommy Robb partnered in the team by experienced English racer John Cooper . The machines were entered into the 750 cc Production Class, a category for road-based machines allowing a limited number of strictly-controlled modifications. They finished in eighth and ninth places. Cooper

792-465: Is currently sold for European, Australia, India and Southeast Asian markets. (Nighthawk 750) Keihin VENA Carbs (2004–2008) (46 cu in) 9500 rpm 7250 rpm (wet) SOHC An overhead camshaft ( OHC ) engine is a piston engine in which the camshaft is located in the cylinder head above the combustion chamber . This contrasts with earlier overhead valve engines (OHV), where

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864-420: Is often called the original Universal Japanese Motorcycle (UJM) and also is regarded as the first motorcycle to be called a "superbike". The CR750 is the associated works racer. Though other manufacturers had marketed the transverse, overhead camshaft , inline four-cylinder engine configuration and the layout had been used in racing engines prior to World War II, Honda popularized the configuration with

936-531: Is possible. The first known automotive application of timing belts to drive overhead camshafts was the 1953 Devin-Panhard racing specials built for the SCCA H-modified racing series in the United States. These engines were based on Panhard OHV flat-twin engines, which were converted to SOHC engines using components from Norton motorcycle engines. The first production car to use a timing belt

1008-473: The 240 Landmarks of Japanese Automotive Technology . Although the CB750 nameplate has carried on throughout multiple generations, the original CB750 line from 1969 to 1983 was succeeded by the CBX750 , which used the CB750 designation for several of its derivatives. Honda of Japan introduced the CB750 motorcycle to the US and European markets in 1969 after experiencing success with its smaller motorcycles. In

1080-590: The AMA , had rules that allowed racing by production machines only, and restricted overhead-valve engines to 500 cc whilst allowing the side-valve Harley Davidsons to compete with 750 cc engines. Honda knew that what won on the race track today, sold in the show rooms tomorrow, and a large engine capacity road machine would have to be built to compete with the Harley Davidson and Triumph twin-cylinder machines. Hansen told Soichiro Honda that he should build

1152-517: The CB1100 , which although well over 750cc in displacement and fuel-injected was marketed as a spiritual successor to the CB750, both in style and in concept; this motorcycle would be later sold to Europe and North America from 2013 until 2022. In 2023, Honda Motor Europe Ltd revived the CB750 nameplate once more in the form of the CB750 Hornet. This new model, though sharing the same name, takes

1224-461: The CB400A , CM400A , and CM450A ). Cycle World tested the 1976 CB750A's top speed at 156 km/h (97 mph), with a 0 to 60 mph (0 to 97 km/h) time of 10.0 seconds and a standing 1 ⁄ 4 mile (0.40 km) time of 15.90 seconds at 138.95 km/h (86.34 mph). Braking from 60 to 0 mph (97 to 0 km/h) was 39 m (129 ft). From 1982 through 2003, with

1296-601: The CBX750 yet also borrowing numerous components from other bikes such as the CBR600F2 , Goldwing and CB-1. The RC38 Nighthawk 750 differed from the RC42 CB750 by taking on a more basic, budget-friendly approach with its packaging; instead of the CB750's dual front disc and single rear disc brake setup, the Nighthawk 750 instead made use with a single disc brake in the front and a rear drum brake. The fork rake angle on

1368-551: The Duesenberg Model J , which was powered by a DOHC straight-eight engine. The 1931–1935 Stutz DV32 was another early American luxury car to use a DOHC engine. Also in the United States, the DOHC Offenhauser racing engine was introduced in 1933. This inline-four engine dominated North American open-wheel racing from 1934 until the 1970s. Other early SOHC automotive engines were the 1920–1923 Wolseley Ten ,

1440-665: The Honda DN-01 but with a conventional gearbox shifted automatically, similar to a " Tiptronic " system, and without a hand-operated clutch rather than a hydrostatic drive . To date, the VFR1200 has not sold particularly well, as buyers have tended to favour the smaller VFR800F (RC79). Honda have permitted the Ariel Motor Company , British makers of the Ariel Atom sports car, to use the VFR1200's V4 engine in

1512-569: The 'pseudo' cruiser bike aesthetic that was specifically catered for the North American market at the time along with offering certain upmarket features, one notable feature being hydraulic valves . Along with the normal CB750 1982-1983 variants the CB750SC Nighthawk would be offered. The Nighthawk 750SC had a 749cc 4-stroke engine with a 5-speed manual transmission, chain drive, front disc and rear drum brakes. Also exclusive to

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1584-537: The 1903 Marr Auto Car SOHC engine built in the United States. The first DOHC engine was a Peugeot inline-four racing engine which powered the car that won the 1912 French Grand Prix . Another Peugeot with a DOHC engine won the 1913 French Grand Prix , followed by the Mercedes-Benz 18/100 GP with an SOHC engine winning the 1914 French Grand Prix . The Isotta Fraschini Tipo KM — built in Italy from 1910–1914—

1656-427: The 1925-1948 Velocette K series , the 1931-1957 Norton International and the 1947-1962 Norton Manx . In more recent times, the 1950-1974 Ducati Single , 1973-1980 Ducati L-twin engine , 1999-2007 Kawasaki W650 and 2011-2016 Kawasaki W800 motorcycle engines have used bevel shafts. The Crosley four cylinder was the last automotive engine to use the shaft tower design to drive the camshaft, from 1946 to 1952;

1728-417: The 1928-1931 MG 18/80 , the 1926–1935 Singer Junior and the 1928–1929 Alfa Romeo 6C Sport . Early overhead camshaft motorcycles included the 1925–1949 Velocette K Series and the 1927–1939 Norton CS1 . The 1946–1948 Crosley CC Four was arguably the first American mass-produced car to use an SOHC engine. This small mass-production engine powered the winner of the 1950 12 Hours of Sebring . Use of

1800-490: The 1960s, and lessons learned from racing were applied to the CB750. The CB750 was targeted directly at the US market after Honda officials, including founder Soichiro Honda , repeatedly met US dealers and understood the opportunity for a larger bike. In 1967 American Honda's service manager Bob Hansen flew to Japan and discussed with Soichiro Honda the possibility of using Grand Prix technology in bikes prepared for American motorcycle events. American racing's governing body,

1872-737: The CB750, and the layout subsequently became the dominant sport bike engine layout. The CB750 is included in the AMA Motorcycle Hall of Fame Classic Bikes; was named in the Discovery Channel 's "Greatest Motorbikes Ever"; was in The Art of the Motorcycle exhibition, and is in the UK National Motor Museum . The Society of Automotive Engineers of Japan, Inc. rates the 1969 CB750 as one of

1944-646: The European market in 2001 and in 2003 the Nighthawk 750 was discontinued in North America, though the CB750 would continue in Japan until 2008 when 2007 automobile exhaust gas regulations went into effect. This would lead the CBR -based Honda Hornet CB600F and later NC700 series to eventually take over the role as Honda's middleweight standard bike offerings in both Europe and North America. In 2010, Honda released

2016-599: The Honda models offered at the time would be known as "customs"; this included but was not limited to the CB900C , CX500C , CM250C and the CB750C, and these bikes would prove to be the most popular with American consumers. Therefore, expanding upon the niche that the CB750C "Custom" had initiated along with its "custom" stable mates, a new series of bikes appeared with the surname "Nighthawk" . These bikes would continue to take on

2088-450: The Nighthawk 750 was slightly increased and conventional twin hydraulic shock absorbers were used instead of the CB750's gas-charged absorbers; the Nighthawk's foot rest were welded to the frame, rather than being interchangeable like on the CB750 and the styling for the Nighthawk was given a more 'retro', smoother reworking that was reminiscent of the Nighthawk bikes of the early 1980s. The engine, exhaust, transmission, gearing and gauges were

2160-624: The Nighthawk variant was Honda's TRAC (Torque Reactive Anti-Dive System). Because of the 1983 motorcycle tariff , the Nighthawk CB750SC was soon replaced by the smaller, yet more sporty and sophisticated CB700SC Nighthawk S . This new motorcycle was a downsized version of the CB750SC Nighthawk S, the export variant of the CB750's successor, the CBX750 After the discontinuation of the CB700SC Nighthawk S in 1986 and

2232-632: The North American Market; soon growing demand emerged for a return towards the traditional UJM style that had fallen out of prominence due to market segmentation. Also in 1989, Kawasaki had successfully released the Zephyr 400 in the Japanese market and soon 550cc and 750cc versions would debut for export markets as well, which was an indicator that a return to form was needed in order to meet demand both at home and abroad. Honda responded in

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2304-422: The United States, with the A suffix designating "Automatic", for its automatic transmission. Although the two-speed transmission includes a torque converter typical of an automatic transmission, the transmission does not automatically change gears for the rider. Each gear is selected by a foot-controlled hydraulic valve/selector (similar in operation to a manual transmission motorcycle). The foot selector controls

2376-468: The V4 configuration has been embraced by Aprilia, Ducati, Suzuki, Yamaha & Norton . Compared to an in-line four, the advantages of a 90° V4 engine include compactness, narrow width, and perfect primary balance giving a smooth and nearly vibration-free operation. A disadvantage is that it is more expensive to manufacture, and, just like a V-twin , more difficult to locate ancillaries and inlet & exhaust systems. In 1982 VF models were introduced to

2448-469: The VFR750 motorcycles featuring gear-driven over head cams and a very high build quality. The first three or four iterations of VFR motorcycles re-established Honda's reputation for quality, and the motorcycles received almost universal praise from journalists and riders alike. The VFR was originally a 750 cc, but became an 800 cc in due course. New models featured technological innovation, such as

2520-413: The application of high pressure oil to a single clutch pack (one clutch for each gear), causing the selected clutch (and gear) to engage. The selected gear remains selected until changed by the rider, or the kickstand is lowered (which shifts the transmission to neutral). The CB750A was sold in the North American and Japanese markets only. The name Hondamatic was shared with Honda cars of the 1970s, but

2592-411: The bike's value were its electric starter , kill switch , dual mirrors, flashing turn signals, easily maintained valves, and overall smoothness and low vibration both under way and at a standstill. Much later models from 1991 included maintenance-free hydraulic valves. Unsure of the bike's reception and therefore unable to accurately gauge demand for the new bike, Honda limited its initial investment in

2664-519: The block, and were known as "tower shafts". An early American overhead camshaft production engine was the SOHC straight-eight engine used in the 1921–1926 Duesenberg Model A luxury car. In 1926, the Sunbeam 3 litre Super Sports became the first production car to use a DOHC engine. In the United States, Duesenberg added DOHC engines (alongside their existing SOHC engines) with the 1928 release of

2736-461: The camshaft (usually a timing chain in modern engines) is more complex in an OHC engine, such as the 4-chain valvetrain of the Audi 3.2 or the 2 meter chain on Ford cammers. Another disadvantage of OHC engines is that during engine repairs where the removal of the cylinder head is required, the camshaft engine timing needs to be reset. In addition, an OHC engine has a large cylinder head to accommodate

2808-408: The camshaft is located below the combustion chamber in the engine block . Single overhead camshaft (SOHC) engines have one camshaft per bank of cylinders . Dual overhead camshaft (DOHC, also known as "twin-cam" ) engines have two camshafts per bank. The first production car to use a DOHC engine was built in 1910. Use of DOHC engines slowly increased from the 1940s, leading to many automobiles by

2880-409: The camshaft is usually transferred to the valves either directly (using a tappet) or indirectly via a rocker arm . A dual overhead cam , double overhead cam , or twin-cam engine has two camshafts over each bank of the cylinder head, one for the intake valves and another for the exhaust valves. Therefore there are two camshafts for a straight engine and a total of four camshafts for a V engine or

2952-510: The camshaft or an extra set of valves to increase the volumetric efficiency , so that with the same displacement as an OHV engine, the OHC engine will end up being the physically larger of the two mostly due to the enlarged cylinder head. The other main advantage of OHC engines is that there is greater flexibility to optimise the size, location and shape of the intake and exhaust ports, since there are no pushrods that need to be avoided. This improves

Honda VF and VFR - Misplaced Pages Continue

3024-415: The camshaft. Timing belts are inexpensive, produce minimal noise and have no need for lubrication. A disadvantage of timing belts is the need for regular replacement of the belt; recommended belt life typically varies between approximately 50,000–100,000 km (31,000–62,000 mi). If the timing belt is not replaced in time and fails and the engine is an interference engine , major engine damage

3096-466: The crankshaft and the camshaft is commonly used in diesel overhead camshaft engines used in heavy trucks. Gear trains are not commonly used in engines for light trucks or automobiles. Several OHC engines up until the 1950s used a shaft with bevel gears to drive the camshaft. Examples include the 1908–1911 Maudslay 25/30 , the Bentley 3 Litre , the 1917-? Liberty L-12 , the 1929-1932 MG Midget ,

3168-443: The early 2000s using DOHC engines. In an OHC engine, the camshaft is located at the top of the engine, above the combustion chamber . This contrasts the earlier overhead valve engine (OHV) and flathead engine configurations, where the camshaft is located down in the engine block . The valves in both OHC and OHV engines are located above the combustion chamber; however an OHV engine requires pushrods and rocker arms to transfer

3240-812: The engine to a new one based on the RVF750R (RC45) and a slight capacity increase led to later models being designated the " VFR800F ". A much larger capacity VFR model, the VFR1200F , was revealed at the Tokyo Motor Show in October 2009. The new 1,200 cc (73 cu in) narrow-angle SOHC V4 engine does not use the V-Tec design of the smaller VFRs. It has an optional six-speed push-button operated dual clutch transmission with three modes: automatic, sport and manual. The modes are similar to those on

3312-490: The engine was changed to a wet sump instead of dry sump type. A lockout safety device prevents the transmission from moving out of neutral if the side stand is down. There is no tachometer but the instruments include a fuel gauge and gear indicator. For 1977 the gearing was revised, and the exhaust changed to a four-into-two with a silencer on either side. Due to slow sales the model was discontinued in 1978, though Honda did later introduce smaller Hondamatic motorcycles (namely

3384-519: The exception of several years, Honda produced a CB750 known as the Nighthawk 750 . As the motorcycle market in the early 1980s began to experience segmentation and the prevalence of UJMs began to dwindle, Honda made efforts to hold its territory on the market by offering more specific variants of their existing bikes as the company was still in the midst of researching and developing dedicated sportbike and cruiser lines. The cruiser variant of many of

3456-490: The gas flow through the engine, increasing power output and fuel efficiency . The oldest configuration of overhead camshaft engine is the single overhead camshaft (SOHC) design. A SOHC engine has one camshaft per bank of cylinders, therefore a straight engine has a total of one camshaft and a V engine or flat engine has a total of two camshafts (one for each cylinder bank). Most SOHC engines have two valves per cylinder, one intake valve and one exhaust valve. Motion of

3528-527: The introduction of very light inline-four motorcycles by competing firms led Honda to downgrade its racing plans. Honda's VF model lineup had engine capacities ranging from 400 cc to 1,000 cc. Another Honda, the shaft-driven ST1100 also featured a V4 engine, but this touring motorcycle does not form part of the VF series. Prior to its adoption by Honda, the V4 design had been used only rarely for motorcycles, most notably by Matchless . In modern times,

3600-608: The late 1960s Honda motorcycles were, overall, the world's biggest sellers. There were the C100 Cub step-through—the best-selling motorcycle of all time—the C71, C72, C77 and CA77/8 Dreams; and the CB72/77 Super Hawks/Sports. A taste of what was ahead came with the introduction of the revolutionary CB450 DOHC twin-cylinder machine in 1966. Profits from these production bikes financed the successful racing machines of

3672-407: The motion from the camshaft up to the valves, whereas an OHC engine has the valves directly actuated by the camshaft. Compared with OHV engines with the same number of valves, there are fewer reciprocating components and less valvetrain inertia in an OHC engine. This reduced inertia in OHC engines results in less valve float at higher engine speeds (RPM). A downside is that the system used to drive

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3744-420: The motorcycle transmission was not fully automatic. The design of the transmission is similar in concept to the transmission in Honda's N360AT , a kei car sold in Japan from 1967 to 1972. The CB750A uses the same engine as the CB750, but detuned with lower 7.7:1 compression and smaller carburettors producing a lower output, 35.0 kW (47.0 hp). The same oil is used for the engine and transmission, and

3816-402: The need for more variation of racing motorcycle and changed the rules from 1970, by standardizing a full 750 cc displacement for all engines regardless of valve location or number of cylinders, enabling Triumph and BSA to field their 750 cc triples instead of the 500 cc Triumph Daytona twins. The Honda factory responded by producing four works-racer CR750s, a racing version of

3888-434: The non-US models with later revisions including changing wheel sizes from 16" front & 18" rear to 17" front and rear, larger diameter forks and the fairing was slightly modified. After this was a series of VFR models which featured various innovations, including a single-sided swingarm , linked braking , ABS , and VTEC . In due course the geared cam drive was dropped in favour of cheaper chain-drive. A total redesign of

3960-595: The previous production year and the introduction of the V65 and the Interceptor. Cam-wear problems surfaced during 1984 in the larger displacement bikes, which, by the time it was corrected, led to eight factory cam revisions over the course of just one year. The 748 cc VFR750F (RC24) was introduced in 1986, and was over-engineered in a bid to re-establish a reputation for reliability. It had an alloy beam frame, gear driven cams. This version underwent constant revision of

4032-463: The production CB750, ridden by UK-based Ralph Bryans , Tommy Robb and Bill Smith under the supervision of Mr Nakamura, and a fourth machine under Hansen ridden by Dick Mann . The three Japanese-prepared machines all failed during the race with Mann just holding on to win by a few seconds with a failing engine. Hansen's race team's historic victory at the March 1970 Daytona 200 with Dick Mann riding

4104-455: The production dies for the CB750's engine by using a technique called permanent mould casting (often erroneously referred to as sandcasting), rather than diecasting. The bike remained in the Honda line up for ten years, with a production total over 400,000. Note: All CB750 engines are air/oil-cooled, as opposed to liquid-cooled Year and model code: In 1976, Honda introduced the CB750A to

4176-597: The public at the Cologne Motorcycle Show with a V4 engine mounted in a square-tube steel frame. That very year, reliability and quality control problems arose, possibly due to new automated production equipment at Honda's plant in Hamamatsu , Japan. Regardless, Honda sold out its first year's inventory of Sabres and the Magnas were not far behind. 1983 saw the engine revised to correct the problems from

4248-454: The rights to the Crosley engine format were bought by a few different companies, including General Tire in 1952, followed by Fageol in 1955, Crofton in 1959, Homelite in 1961, and Fisher Pierce in 1966, after Crosley closed the automotive factory doors, and they continued to produce the same engine for several more years. A camshaft drive using three sets of cranks and rods in parallel

4320-511: The same on both bikes. The RC42 CB750 was widely adopted at riding schools throughout Japan to prepare riders for their large motorcycle license exams due in part to it's smooth power delivery, predictable handling, neutral ergonomics, reliability and maintainability. The entry-level 1992-2008 Nighthawk 250 was derived from the Nighthawk 750. In 2007 Honda Japan announced the CB750 Special Edition. This limited edition run

4392-730: The starting point for both Mercedes' and Rolls-Royce's aircraft engines. Mercedes created a series of six-cylinder engines which culminated in the Mercedes D.III . Rolls-Royce reversed-engineered the Mercedes cylinder head design based on a racing car left in England at the beginning of the war, leading to the Rolls-Royce Eagle V12 engine. Other SOHC designs included the Spanish Hispano-Suiza 8 V8 engine (with

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4464-661: The summer of 1991 with the RC38 Nighthawk 750, which was marketed in both North America and Japan, though for the latter only for a single year as the RC39 CB750 Nighthawk. The following year, the higher spec RC42 CB750 would debut for Europe and Japanese markets (in Europe it went by either CB750F2 or CB Seven-Fifty ). Both the RC38/39 and RC42 were parts-bin specials , mainly being mechanical descendants of

4536-631: The tariff being lifted in 1987 Honda decided not to follow up with the larger CB750SC Nighthawk S, which was offered for the Canadian market. Instead, as was typically the case for many Japanese corporations during the bubble years , Honda began to experiment with its standard bike offerings by first releasing the V-twin NT650 in 1988 and later both the boutique-developed cafe racer GB500 and CBR400RR derived CB-1 in 1989. Though innovative in their own right, these motorcycles had very short lives in

4608-417: The time of the bike's introduction. Cycle World called it a masterpiece, highlighting Honda's painstaking durability testing, the bike's 124 mph (200 km/h) top speed, the fade-free braking, the comfortable ride, and the excellent instrumentation. The CB750 was the first modern four-cylinder machine from a mainstream manufacturer, and the term superbike was coined to describe it. Adding to

4680-447: The timing between each camshaft and the crankshaft. This affords better fuel economy by allowing a broader torque curve. Although each major manufacturer has their own trade name for their specific system of variable cam phasing systems, overall they are all classified as variable valve timing . The rotation of a camshaft is driven by a crankshaft . Many 21st century engines use a toothed timing belt made from rubber and kevlar to drive

4752-437: The top of the engine. Large aircraft engines— particularly air-cooled engines— experienced considerable thermal expansion, causing the height of the cylinder block to vary during operating conditions. This expansion caused difficulties for pushrod engines, so an overhead camshaft engine using a shaft drive with sliding spline was the easiest way to allow for this expansion. These bevel shafts were usually in an external tube outside

4824-414: The valves directly via a bucket tappet . A DOHC design permits a wider angle between intake and exhaust valves than in SOHC engines, which improves the air-fuel mixture's flow through the engine. A further benefit is that the spark plug can be placed at the optimum location, which in turn improves combustion efficiency . Another newer benefit of DOHC engine design is the ability to independently change/phase

4896-481: Was interviewed in UK monthly magazine Motorcycle Mechanics , stating both riders were unhappy with their poor-handling Hondas, and that he would not ride in the next year's race "unless the bikes have been greatly improved". In 1973, Japanese rider Morio Sumiya finished in sixth place in the Daytona 200-Mile race on a factory 750. Under development for a year, the CB750 had a transverse straight-four engine with

4968-520: Was one of the first production cars to use an SOHC engine. During World War I, both the Allied and Central Powers ; specifically those of the German Empire 's Luftstreitkräfte air forces, sought to quickly apply the overhead camshaft technology of motor racing engines to military aircraft engines. The SOHC engine from the Mercedes 18/100 GP car (which won the 1914 French Grand Prix) became

5040-539: Was put forth to commemorate the 25th anniversary of "Fast Freddie" Spencer joining the Honda Grand Prix Team and a version of this bike donning the "Digital Silver Metallic" color of the CB750 racebike Spencer used in the 1981 AMA Superbike championship was offered alongside a version that was painted in "Candy Blazing Red" reminiscent of the CBX1000 . The CB750F2/ CB Seven-Fifty was discontinued for

5112-472: Was the 1962 Glas 1004 compact coupe. Another camshaft drive method commonly used on modern engines is a timing chain , constructed from one or two rows of metal roller chains . By the early 1960s most production automobile overhead camshaft designs used chains to drive the camshaft(s). Timing chains do not usually require replacement at regular intervals, however the disadvantage is that they are noisier than timing belts. A gear train system between

5184-474: Was used in the 1920–1923 Leyland Eight luxury car built in the United Kingdom. A similar system was used in the 1926-1930 Bentley Speed Six and the 1930-1932 Bentley 8 Litre . A two-rod system with counterweights at both ends was used by many models of the 1958-1973 NSU Prinz . Among the first overhead camshaft engines were the 1902 Maudslay SOHC engine built in the United Kingdom and

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