The CB750 is an air-cooled, transverse, in-line-four-cylinder-engine motorcycles 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 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"; 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.

History Honda of Japan introduced 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 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.

Early racing In 1967 American Honda's service manager Bob HansenGirdler, Alan. Bob Hansen, 1919–2013 A long and rewarding life. Cycle World 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, 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.Mann and machine, Motorcyclist online Retrieved 13 June 2015 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 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;Motorcycle Sport, UK monthly magazine, April 1969, pp. Cover, 121, 132–133. Honda's 750-4 arrives. "The wide, sweeping handlebars on the machines shown at Brighton are fitted in the US market, but before deciding on whether or not these will be the ones for this country some discussion will take place between Honda UK and dealers and prospective owners". Accessed 15 June 2015Motorcycle Mechanics, May 1969, Showtime – 6-page-special. pp. Cover, 38–39, Honda's Four. "MM takes a close look at the new 4-pot Honda 750". Accessed 15 June 2015 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 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 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 victoryOriginal Honda CB750 by John Wyatt – Bay View Books Ltd 1998 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.Isle of Man TT Races official site 1970 Production 750cc Results Retrieved 13 June 2015 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".Motorcycle Mechanics, December 1970, pp.36–37 John Cooper interview by Charles Deane (editor). Accessed 13 June 2015

In 1973, Japanese rider Morio Sumiya finished in sixth place in the Daytona 200-Mile race on a factory 750.Honda WorldWide, Honda Motor Co., Ltd official site Retrieved 20 June 2015

Production and reception

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$ (US$ 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 the time of the bike's introduction. Cycle World called it a masterpiece, highlighting Honda's painstaking durability testing, the bike's 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 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 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. After the initial run of 7,414 motorcycles Honda switched to die casting, with the initial run of bikes going on to be prized by collectors.Hagery.com: Why do collectors pay double for a Honda CB750 engine cast in sand?, James Hewitt, 02 October 2020 The bike remained in the Honda line up for ten years, with a production total over 400,000.

Models

Note: All CB750 engines are air/oil-cooled, as opposed to liquid-cooled

SOHC Year and model code: 1969 CB750 (6 June), CB750K or CB750K0 (date unknown) 1970 CB750K1 (21 September) 1972 CB750K2 (US 1 March) 1973 CB750K3 (US-only 1 February. K2 elsewhere) 1974 CB750K4 (US/Japan-only, K2 elsewhere) 1975 CB750K5 (US-only, K2/K4 elsewhere), CB750FO, CB750A (Canada-only) The 1975 CB750F had a more streamlined look, thanks in part to a 4-into-1 exhaust and cafe style seat with fiberglass rear. Other changes included the use of a rear disc brake and a lighter crankshaft and flywheel. 1976 CB750K6, CB750F1, CB750A 1977 CB750K7, CB750F2, CB750A1 1978 CB750K8 (US-only), CB750F3, CB750A2

+ModelProduction (rounded figures)Classic Bike Glamorous and Glorious by Mick Duckworth June 2004 issueCB750K053,400CB750K177,000CB750K263,500CB750K338,000CB750K460,000CB750K535,000CB750K642,000CB750K738,000CB750K839,000CB750F15,000CB750F144,000CB750F225,000CB750F318,400CB750A4,100CB750A12,300CB750A21,700

DOHC

1979–1982 CB750K 1979 CB750K 10th Anniversary Edition (5,000 produced for US) 1979–1982 CB750F 1980–1983 CB750C "Custom" 1982–1983 CB750SC Nighthawk 1984–1986 CB750SC Nighthawk S (Horizon in Japan. Export version of the CBX750.) 1991–2003 Nighthawk 750 1992–2008 CB750 (sold as CB750F2 and CB Seven-Fifty in Europe) 2023–present CB750 Hornet (Derived from the 2023 Transalp)

CB750A Hondamatic

In 1976, Honda introduced 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 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. For Japan, it was sold from April 1977 but it was discontinued there before the 1978 models (A2) were introduced. In Japan it was sold as the Honda EARA, with that name being a combination of "Era" with "A" for automatic, while also signifying "Expands Automatic Riding Age". The name Hondamatic was shared with Honda cars of the 1970s, but the motorcycle transmission was not fully automatic. The design of the transmission is similar in concept to the transmission in Honda's N360AT,The Hondamatic Transmission, The Innovative Automatic Transmission: A Breakthrough in Original Thinking, 1968 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 (PW24 rather than PW28) carburettors producing a lower output, . The same oil is used for the engine and transmission, and 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 the CB400A, CM400A, and CM450A). Cycle World tested the 1976 CB750A's top speed at , with a time of 10.0 seconds and a standing time of 15.90 seconds at . Honda's official figures (from the Japanese market) were a top speed of and a 0- time of 14.90 seconds. Braking from was .

Nighthawk 750 & CBX750 derived CB750 Models