Honda CB 750 Four

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Honda (motorcycle)
HONDA.CB750four-1975 02.JPG
CB 750 Four K2 ED 1973
CB 750 Four
Manufacturer Honda Motor Co., Ltd.
Production period 1969 to 1978
class motorcycle
design type Superbike , sports tourer
Motor data
4-cylinder four-stroke engine , OHC valve control , air-cooled, 4 carburettors
Displacement  (cm³) 736
Power  (kW / PS ) 49.3 / 67 at 8,000 min -1
Torque  ( N m ) 59.8 at 7,000 min -1
Top speed (  km / h) 200
transmission 5-speed
Wheelbase  (mm) 1455
Dimensions (L × W × H, mm): 2175 × 870 × 1170 (K2)
Seat height (cm) approx. 81
Empty weight  (kg) 218
Previous model -
successor CB 750 K (Z)

The CB 750 Four is a motorcycle from the Japanese manufacturer Honda . The first mass-produced motorcycle with a four-cylinder in - line engine was a great success worldwide and was manufactured over 550,000 times by 1978. The type, initially only called “Honda Four”, has a transverse engine, chain drive and a hydraulically operated disc brake at the front.

technology

development

Engine CB750 Four K0
4-cylinder in-line engine (SOHC)
Honda CB 750 Four K1 engine with protective bar

After Honda had won all five classes of the (50/125/250/350/500 cm³) motorcycle constructors' championship in 1966 , the decision was made in 1967, with 20 employees under project manager Yoshirou Harada and engine constructor Masaru Shirakura, to develop and Construction of a machine that should set a new reference in the high-speed segment with a safe and comfortable cruising speed. In February 1968 the construction of the engine started. The co-responsible designer was Hitoshi Ikeda.

idea

The blue pre-production model Dream CB 750 Four was first presented to the public on October 25, 1968 at the 15th Tokyo Motor Show . The first series machine was presented in January 1969 at the first US dealer meeting in Las Vegas , Nevada. American Honda Motor Co. President Kihachiro Kawashima announced that it would sell this motorcycle for $ 1,495. The model was built in the Honda factories of Saitama (now Wako Plant), Hamamatsu and later Suzuka from spring 1969 . The production model CB 750 Four K0 (type code 300) was mainly sold in the USA and Japan from mid-1969 . It should cost $ 1,666, or 385,000 yen. This first version of 7,414 copies is known today as the sand cast model and is very popular with enthusiasts.

In the spring of 1973 the CB 750 in Germany cost 6,598 DM including 11%  sales tax , which today corresponds to approx. 10,010 euros. In mid-1975 a CB 750 F1 including VAT cost 7,198 DM (9,638 euros). 7,368 DM (9,468 euros) was the price including VAT for the CB 750 K6 in spring 1976.

With these performance data, the Four was the first motorcycle that left every BMW , Norton and Triumph behind. However, the chassis had significant weaknesses. The hydraulically operated disc brake on the front wheel was new .

This type of motorcycle was built in numerous, repeatedly facelifted versions for almost ten years. The mechanics turned out to be very durable, despite previous concerns from experts. It is not uncommon for the engines of this first 750 four-cylinder series to achieve mileages of over 150,000 km. That too was unusual; In those years, motorcyclists expected a thorough engine overhaul after 30,000 or 40,000 km.

A version with a semi-automatic transmission ( Hondamatic ) with a two-stage hydraulic torque converter was also built from 1976 to 1978, but it was not so well received. In the USA this version was called the CB-750 A (CB 750 A) and in Japan EARA (CB 750 A). The left footshift lever was used to shift down to N (neutral), up to L (low), and further up to D (drive).

The 1970s were also the time of chopper conversions, inspired by the film Easy Rider by and with Peter Fonda . The front forks couldn't be long enough. The manufacturer of such conversions, also based on the CB750, was among others the company AME.

Motorsport

Honda CB 750 Martin, 1972
Quail Motorcycle Gathering 2015

This machine was also successful many times in racing. It was also the time of the tuners who experienced their success stories with this basic machine, including Bimota , Fritz Egli , Eckert, Japauto , Dunstall , Rickman , Rau, Martin, Dresda , Seeley Ernest Walther and Yoshimura.

The first victory in the 10-hour production machine race in Suzuka, Japan in August 1969 went to the Morio Sumiya / Tetsuya Hishiki team, while Yoichi Oguma / Minoru Sato, both teams on the CB 750 Four, went second. The first victory at the 24-hour long-distance race Bol d'Or in Montlhéry / France went to the French Daniel Urdrich and Michel Rougerie with the starting number 61 on September 12, 1969 in a CR 750 for Honda, which was prepared by Alf Briggs of Honda UK . On March 15, 1970, the American Dick Mann drove to victory in the 200-mile American Motorcyclist Association Daytona on a CR 750 with starting number 2. This racing machine was essentially derived from the CB 750 Four. Team Gérard Debrock / Roger Ruiz drove to victory in the 1972 Bol d'Or 24-hour long-distance race in Le Mans. The European Endurance Championship was won by the Godier Genoud team that year. The Debrock / Thierry Tchernine team drove to victory in the 1973 Bol'Or 24-hour endurance race in Le Mans. In 1975 the team Roger Ruiz / Christian Huguet became world champions in the FIM Endurance. From 1976 to 1979 the RCB 1000 (941 cm³ / 997 cm³), which now had two overhead camshafts, was in the endurance races of the Coupe d'Endurance with the drivers Jean-Claude Chemarin / Christian Leon, Christian Huguet / Pentti Korhonen, Jean-Claude Chemarin / Alex George, G. Green / Maurice Maingret with the 1000 Japauto VX941 Honda engine, Stanley Woods / Charlie Williams and other teams very successful. In 1977 Phil Read drove to victory in the Formula 1 class at the Isle of Man TT.

Ultimately, the attempts to break the absolute speed record for motorcycles with a machine built by Reaction Dynamics and equipped with two turbo-charged CB 750 engines resulted in a class record from 1971 to 1972. The Honda Hawk averaged 374 km / h and driven in one direction at 461 km / h.

Names

In Japan, the CB 750 Four is also known as the CB Nanahan or Dream CB 750 Four .

Award

It was voted motorcycle of the century by motorcyclists in 1999.

Gallery images

Model overview

Type model code Displacement kW ( PS ) at min −1 tank Weight construction time Production
(vehicles)
CB 750 K0 300 736 cm 3 49.3 (67) 8000 18th 205 1969 7,414
CB 750 K1 + P (policy) 300 736 cm 3 49.3 (67) 8000 17th 218 1970-1971 77,000
CB 750 K2 (for D) + P 341 736 cm 3 49.3 (67) 8000 17th 235 1972-1975 63,500
CB 750 K3-K5 (USA) 341 736 cm 3 49.3 (67) 8000 17th 235 1972-1988
CB 750 K6 341 736 cm 3 46.3 (63 in D) 8000 17th 235 1976 42,000
CB 750 K7 (K8 USA) 405 736 cm 3 49.3 (67) 8000 19 / 19.5 253.5 1977-1988 38,000
CB 750 CB A 393 736 cm 3 34.5 (47) 7500 19.5 241/262 1976-1988 8,100
CB 750 F / F1 392 736 cm 3 49.3 (67) 8500 18/17 227 1975-1977 44,000
CB 750 F2 / F3 (FIII USA) 410 736 cm 3 53.7 (73) 9000 18th 247 1977-1988 25,000

Production numbers

model construction time Production
(vehicles)
Series K0 – K8 1969-1988 442,500
Series F0 – F3 1975-1988 102,500
total 1969-1988 553.100

Model history

After the outstanding success of the CB 750 Four, Honda began to transfer this concept to the smaller displacements. Thus, the CB 500 Four and 1972 the CB 350 Four emerged as further models .

Trivia

The comic figure Eduard Nockenfell (fr. Edouard Bracame) of the Joe Bar Team drives a Honda CB 750 Four and Aime Gafone drives a Honda 750 Daytona replica .

successor

Honda CB 750 F (1981), in the design of the CB 900 F Bol d'Or

Only when the Kawasaki Z 1 “Super four” (later Z 900) with 82 hp (US version - 79 hp in Germany) came out in 1972 did the sales figures weaken. Honda phased out the first 750 series (K0-K8) in 1978 and replaced it with the CB 750 K (RC 01) with the 77 hp DOHC engine, which was derived from the then very successful Honda racing engine of the RCB1000 .

At the same time, the Honda CB 900 Bol d'Or was developed, of this type there was also a smaller displacement version, the CB 750 F (RC04) Bol d'Or with the engine of the CB 750 K (RC 01), which was replaced by a modified exhaust system (4-2) now had 79 hp. This legitimate successor to the CB 750 was initially only available in Japan, Canada and the USA and was derived from the top-of-the-line version CB 900 F Bol d'Or, which was only sold abroad. In Japan itself, it was hard because of the license provisions, motorcycles with more than 750cc in the traffic to take. The name Bol d'Or was reminiscent of Honda's success at the Bol d'Or , the 24-hour motorcycle race in France.

At the beginning of the 1990s, Honda added a modernly designed and then quite successful CB 750 Four to its range in order to pick up on the old glorious name: after a decade of interruption, the third, fundamentally new version of a four-cylinder sports tourer. This version is called CB Sevenfifty and was built from 1992 to 2002.

On October 23, 1999, for the 30th birthday of the in-line Four, Honda surprised the public at the Tokyo Motor Show with a study (prototype) called the CB Four , which visually resembled the old CB 750 Four in many ways, but did not go into series production. In this study, however, the engine was a specimen with two overhead camshafts DOHC and there were two disc brakes in the front wheel.

The four in today's streetscape

Nowadays, especially the machines of the first series, the models K0-K7 (K8), are valued as old-timer motorcycles in good condition at a multiple of their former price. However, models in their original condition are rare, which is partly due to the fact that the Fours were a "grateful" foundation for conversion and tuning measures; On the other hand, the exhaust systems in particular have always been susceptible to rust and expensive or have not been available for a number of years, so that a wide variety of 4-in-1 systems were added. For some time (around 2006) the original 4-in-4 exhaust systems have been available again. A conversion of the Four that is accepted in classic car circles is to equip it with a second disc brake at the front. Since there are mounting points for the brake caliper as standard, this conversion can be carried out without any problems.

literature

  • Joachim Kuch: Type compass Honda motorcycles since 1970 , 1st edition, Motorbuch Verlag, Stuttgart 2000, ISBN 3-613-02061-0 .
  • Reinhard Hopp: Honda CB 750 The story of a legend , Motorbuch Verlag, Stuttgart 1998, ISBN 3-613-01920-5 .
  • Reinhard Hopp: Honda CB 750 The motorcycle of the century , Motorbuch Verlag, Stuttgart 2005, ISBN 3-613-02545-0 .
  • Reinhard Hopp: Honda The history of the legendary four-cylinder since 1969 , Motorbuch Verlag, Stuttgart 2010, ISBN 978-3-613-03211-8 .
  • Giorgio Sarti: Honda CB 750 Four , Heel Verlag GmbH, Königswinter 2014, ISBN 978-3-86852-899-2 .
  • The motorcycle : “Thankful steamer”, long-distance test Honda CB 750 over 40,000 km (from December 1972), issue 10/75 of May 17, 1975, Motor-Presse-Verlag Stuttgart
  • The motorcycle: Three 750s in comparison: Suzuki GT 750, BMW R 75/6, Honda CB 750 F1 , issue 25/75 of December 13, 1975, Motor-Presse-Verlag Stuttgart
  • The motorcycle: "A matter of opinion", double test Honda CB 500/750 (CB 500 K4 / CB 750 K6), issue 13/76 of June 13, 1976, Motor-Presse-Verlag Stuttgart

Web links

Commons : Honda CB750  - Collection of pictures, videos and audio files

Individual evidence

  1. ^ Ernst Leverkus: The motorcycles of the 50s, 60s and 70s , special edition 1st edition, Motorbuch Verlag, Stuttgart 2003, ISBN 3-613-02366-0
  2. This figure was based on the template: Inflation determined, rounded to 100 EUR and applies to the previous January
  3. Das Motorrad, Issue 25/75: Three 750s in comparison: Suzuki GT 750, BMW R 75/6, Honda CB 750 F1
  4. Das Motorrad, Issue 13/76: Double test of the Honda CB 500/750
  5. Dick Keller: The Honda Hawk . clingonforlife.blogspot.de, accessed on November 10, 2014.