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64-440: 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 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

128-803: A Harley-Davidson in his first Grand National race, the Daytona 200 . At this time, the race was held on the Daytona Beach Road Course . He slowly made a name for himself in his first three years, and he finished in the top ten in the season points for the first time in 1957. Mann had a second-place finish at the Daytona 200 and Laconia in 1958. He had his first national victory at the Peoria, Illinois Tourist Trophy (TT) in 1959. He finished second in points in that year. In 1963 Mann won his first AMA Grand National title. He had five podium finishes. He clinched

192-473: A cinder running track at the area schools. He would also ride on the cow trails in the area, experiences that would later help him in motocross. After high school, he started helping at fellow Motorcycle Hall of Fame member Hap Alzina 's BSA shop in Oakland as a mechanic. In the summer of 1954 he started touring as an amateur with professional Al Gunter. Mann turned expert in 1955, and finished seventh on

256-487: A category for road-based machines allowing a limited number of strictly-controlled modifications. They finished in eighth and ninth places. Cooper 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

320-412: 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

384-515: A few seconds with a failing engine. Hansen's race team's historic victory at the March 1970 Daytona 200 with Dick Mann riding 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,

448-430: 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

512-486: 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

576-440: 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

640-781: 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 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;

704-464: 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

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768-444: Is called "SuperMann". Over 400 people came to see the opening. Throughout his racing career, Mann was an innovative designer and fabricator of frames and related hardware. He also worked for and acted as consultant to several motorcycle manufacturers. In 1966, Dick designed and fabricated a large diameter backbone Chromoly frame for his BSA A65 . Elements of its geometry became the hallmark of several of his designs. In 1967, he

832-801: 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) Air-cooled Air-cooled engines are widely seen in applications where weight or simplicity 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

896-418: 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

960-507: 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

1024-453: 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

1088-632: 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

1152-766: The International Six Days Enduro ) on the Isle of Man , earning a Bronze Medal on an OSSA 350. Mann was awarded the AMA Dud Perkins Award for his contributions to the sport in 1995. He was inducted in the Motorsports Hall of Fame of America in 1993. He was still competing in vintage racing when he was inducted in the Motorcycle Hall of Fame in 1998. The Motorcycle Hall of Fame opened an exhibit honoring Mann's career on July 27, 2006. The exhibit

1216-572: The Ossa Wildfire SS tank in 1967, the DMR tank, and the tank and seat that graced the first 500Z prototypes in 1968. That prototype had influence on later designs such as Craig Vetter's Triumph X75 Hurricane. In 1975 Mann started designing frames for the Yamaha XT 500 . In all he sold some 200 frames for this engine in four marques, the final frames being completed in 1982. He also designed variations for

1280-552: 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

1344-638: 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. Dick Mann Dick Mann (June 13, 1934 – April 26, 2021)

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1408-410: The 500 cc Triumph Daytona twins. The Honda factory responded by producing four works-racer CR750s, a racing version of 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

1472-614: The CB750 motorcycle to the US and European markets in 1969 after experiencing success with its smaller motorcycles. In 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

1536-412: The CB750, "the most sophisticated production bike ever" at 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

1600-539: The CB750A to 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

1664-519: The Daytona 200-Mile race on a factory 750. Under development for a year, the CB750 had a transverse straight-four engine with 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

1728-627: 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

1792-603: The Honda XL/XR500 and the Suzuki DR/SP370. All the production frames were constructed by Terry Knight based on each of Mann's home built and extensively tested prototypes. He owned a business specializing in restoring and selling vintage race motorcycles. He also actively participated in American Historic Racing Motorcycle Association (AHRMA) [1] Vintage Moto-Cross racing. His wife's name

1856-587: 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

1920-677: 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

1984-565: 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

Honda CB750 and CR750 - Misplaced Pages Continue

2048-450: 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

2112-600: 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

2176-614: 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

2240-411: 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

2304-410: The decade with one of the biggest wins of his career. He won the 1970 Daytona 200 , a race that he had not won in fifteen attempts. Mann beat former world champion Mike Hailwood , and rising stars Gene Romero and Gary Nixon . It was the first win by Honda in an AMA national, and it happened at the series' premiere event. In 1971 Mann won his second Grand National title on a BSA . He became

2368-489: 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

2432-513: 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

2496-568: 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,

2560-418: 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

2624-506: 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,

Honda CB750 and CR750 - Misplaced Pages Continue

2688-439: The new bike, Honda limited its initial investment in 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

2752-827: The oldest series champion in the history of the series. He won the 1971 season opener at the Houston TT. He won his second Daytona 200 in the second race of the season. The win earned him a spot on the May 1971 cover of the AMA magazine . Mann also won road races at Pocono Raceway and Kent, Washington . He was named AMA's Most Popular Rider of the Year in 1971. Mann became the first rider to win motorcycle racing's career Grand Slam by winning in Grand National on mile, half mile, short-track, TT, and road racing circuits. Mann won races in 1972. His final win

2816-425: The possibility of using Grand Prix technology in bikes prepared for American motorcycle events. American racing's governing body, 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

2880-416: The pre-production versions appeared with a high and very wide handlebar intended for the US market. The AMA Competition Committee recognised 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

2944-523: The pro circuit spanned the early 1950s to the mid-1970s. He was known for being one of the most talented and versatile riders, and for wearing a cheap straw hat while working on his motorcycle. Born Richard Scott Mann in Salt Lake City, Utah , Mann rode his first motorcycle as a teenager when he delivered papers on a Cushman scooter in Richmond, California . He learned how to ride dirt competitively on

3008-481: 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

3072-498: The revolutionary CB450 DOHC twin-cylinder machine in 1966. Profits from these production bikes financed the successful racing machines of 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

3136-501: 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

3200-454: 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

3264-458: 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

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3328-587: 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

3392-620: 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

3456-417: The term superbike was coined to describe it. Adding to 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

3520-618: The title by winning on September 21 Ascot Park in Gardena, California . Mann continued to win races and place high in the points standings before his next title eight years later. He also helped pioneer motocross during that time, and raced in several motocross races in the 1960s and early 1970s. He represented the United States in the Transatlantic Trophy match race series. The series faced little-known American racers against Great Britain 's well-known pavement riders. Mann started

3584-541: 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 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";

3648-454: 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

3712-578: 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

3776-617: Was an American professional motorcycle racer . He was a two-time winner of the A.M.A. Grand National Championship . Mann was inducted in the Motorsports Hall of Fame of America in 1993, and the Motorcycle Hall of Fame in 1998. He was one of the few riders to ride motocross and Observed Trials as well as dirt flat tracks , TT (tourist trophy) and road racing . Mann was the second-winningest rider in AMA Grand National Series history with 24 national victories. His career on

3840-543: Was at Peoria, the site of his first win. He remained competitive in 1973, still on a BSA, and finished in the Top 10 in points at age 40. Mann retired in 1974. He had raced in 240 nationals, and he finished in the Top 10 in points in every season except one between 1957 and 1973. In 1975 Mann returned to his trail riding roots. He competed on the United States International Six Days Trial team (now

3904-642: 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 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

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3968-524: 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

4032-531: Was retained by John Taylor of Yankee Motor Corp. and incorporated the same design elements into the Yankee 500Z . In 1969 while with Yankee, he designed and worked with Frank Conner of OSSA/West to build the highly successful OSSA /DMR flat tracker. After winning several National races, the DMR was put into a short run of production by Yankee with 150 units being produced in 1970-71. He was also influential on styling. Design elements of an earlier BSA of Dick's appeared on

4096-489: 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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