Honda CB750

The Honda CB 750 Four is a motorcycle by the Japanese manufacturer Honda. The first mass-produced motorcycle with four cylinder in-line engine was a huge success worldwide, and was produced until 1978, more than 550,000 times. The first only " Honda Four" mentioned type has a transverse-mounted engine, chain drive and a hydraulic disc front brakes.

Technology

• Transversely mounted air-cooled four-cylinder inline engine (cylinder 15 degrees in the direction inclined ), an overhead camshaft ( OHC ) with drive via timing chain, operated two valves per cylinder via rocker arms, primary drive by two parallel single roller chains. With dry sump lubrication (3.5 L ), and an oil filter.
• Displacement: 736 cc Bore × Stroke: 61 × 63 mm, compression ratio of 9.0: 1
• Power: 67 hp (49 kW) at 8000 min-1
• Torque: 60 Nm (6.1 mkg ) at 7000 min-1
• 4 Keihin slide carburettor Ø 28 mm
• 4-in -4 Exhaust System
• Tank capacity: 17 liters of which 3 l reserve (K0 = 18 L, K7/K8 = 19 l, CB A = 19.5 l)
• Fuel: Super 95 RON
• Fuel consumption ( min / average / max): 4.84 / 5.77 / 8.04 l/100 km
• Double-loop tubular frame front telescopic fork / rear swingarm with two spring legs
• Kickstarter and electric starter
• Rear-wheel drive via single roller chain 5/8 "x 3/ 8"
• Hydraulically operated disc brake front ( a disc Ø 296 mm ) rear drum brake (Ø 180 x 35 mm)
• Tire dimension front: 3.25-19 (K7 K8 = 3.50-19 )
• Rear tire size: 4.00-18 (K7 K8 = 4.50-17 )
• Wet weight: 235 kg (K2 )
• Gross weight: 385 kg (K2 )
• 12 V system, three-phase alternator 210 W Battery 14 Ah
• Maximum speed: over 200 km / h ( according to the prospectus)
• Acceleration: 0-100 km / h in 4.6 s (according to the prospectus)

Development

After Honda had won all five classes of 1966 ( 50/125/250/350/500 cm ³) Motorcycle Constructors' World Championship, it was decided in 1967, with 20 employees under Project Yoshirou Harada and engine builder as Masaru Shirakura to develop and construction of a machine that should set the high-speed segment with safe and comfortable cruising speed, a new reference. In February 1968 they started the construction of the engine. The co-responsible designer was Hitoshi Ikeda.

Idea

The blue preproduction Dream CB750 Four was first presented to the public on October 25, 1968 at the 15th Tokyo Motor Show. The first production aircraft was on the first U.S. dealer meeting in Las Vegas, Nevada presented in January 1969. The president of American Honda Motor Co., Kihachiro Kawashima announced this bike for 1,495 U.S. dollars to sell. The model was built from the spring of 1969 in the Honda works of Saitama (now Wako Plant), Hamamatsu and Suzuka later. The production model CB 750 Four K0 (type code 300) was sold mainly in the U.S. and Japan from the mid-1969. It should cost 1,666 U.S. dollars or 385,000 yen. This first version of 7414 copies is known today under the name of sand -cast model and much sought after by lovers.

In the spring of 1973, the CB 750 in Germany cost 6,598 DM including 11% VAT, which is about 9,900 euros today. Mid-1975 the cost of a CB 750 F1 incl. DM 7,198 ( 9,400 euros ). DM 7,368 ( € 9,100 ) including VAT was in the spring of 1976, the price. for the CB 750 K6.

With this performance, the Four was the first motorcycle that made any BMW, Norton and Triumph behind. However, the suspension had significant weaknesses. What was new was the hydraulic disc brake on the front wheel.

This type of motorcycle was built in several, repeatedly facelifted versions for almost ten years. The mechanics proved despite previously voiced concerns from the field as very durable. Not infrequently reached the engines of this first 750cc four-cylinder series mileages of over 150,000 km. Even that was unusual; Motorcyclists counted in those years after 30,000 or 40,000 km with thorough Engine Reconditioning.

A version with a semi- automatic transmission ( Hondamatic ) with a two-stage hydraulic torque converter was built from 1976 to 1978, but which was not as well received. In the U.S., this version CB- 750A called (CB 750 A) and in Japan eara ( CB750A ). Was switched from the left pedal down in N (Neutral), up to the speed step L (Low), further to the above for D (Drive).

The 1970s was also the time of the chopper conversions, inspired by the movie Easy Rider with Peter Fonda and. The front forks were not long enough. Manufacturer was among other AME.

Motorsport

In racing, this machine was also often successful. It was also the time the tuner who experienced a success story with this basic machine, Bimota, Fritz Egli, Eckert, Japauto, Dunstall, Rickman, Rau, Martin, Dresda, Seeley and Yoshimura, just to name a few.

The first victory in the 10-hour production machine race in Suzuka Japanese in August 1969 went to the team Morio Sumiya / Tetsuya Hishiki, second were Yoichi Oguma / Minoru Sato, both teams on the CB 750 Four. The first win in the 24 - hour endurance race Bol d'Or at Montlhery / France drove the French Urdrich Daniel and Michel Rougerie with the number 61 on 12 September 1969 one of Alf Briggs by Honda UK made-up CR 750 for a Honda. On March 15, 1970, the Americans Dickmann drove the race of the American Motorcyclist Association Daytona 200 miles on a CR 750 with starting number 2 to victory. This racing machine was essentially derived from the CB 750 Four. At the 24 -hour endurance race Bol d'Or 1972 in Le Mans, the team Gérard Debrock / Roger Ruiz drove to victory. The European Endurance Championship, the team won Godier Genoud this year. At the 24 -hour endurance race Bol'Or 1973 in Le Mans, the team Debrock / Thierry Tchernine drove to victory. In 1975, the team Roger Ruiz / Christian Huguet was World Champion in the FIM Endurance. In the years 1976-1979 the RCB was 1000 (941 cc / 997 cc ), which now had two overhead camshaft, in the endurance race in 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 very successful with the 1000 Japauto VX941 Honda engine, Stanley Woods / Charlie Williams and other teams. 1977 drove Phil Read in class Formula 1 on the Isle of Man TT victory.

Name

In Japan, the CB 750 Four also named CB Nanahan or Dream CB750 Four known.

Award

From motorcyclists, she was elected to the motorcycle of the century in 1999.

Gallery Images

Motor CB 750 Four K0

Honda CB 750 Four K1 engine and front hand guard

Honda CB750 Four K7 of 1978, down to the porters in their original state

Conversion of a chopper CB 750 Four of the first series

Rickman Honda 750 Four 1973

Model Overview

Production figures

Model history

Following the outstanding success of the CB 750 Four Honda began to transfer this concept to the smaller displacements. Thus, the CB 500 Four in 1972, CB originated in a row as more models 1971 350 Four.

Trivia

The comic book character Eduard cam Fell ( fr. Edouard Bracame ) of the Joe Bar Team drives a Honda CB 750 Four and Aime Gafone a Honda 750 Daytona Replica.

Successor

It was not until 1972, the Kawasaki Z1 " Super four" (later Z 900) with 82 HP ( U.S. version - in Germany 79 PS) came out, the sales weakened. Honda was the first 750 series (K0 -K8 ) in 1978 phased out and replaced it with the CB 750 K RC01 with the 77 hp DOHC engine, which was derived from the then highly successful Honda racing engine of RCB in 1000.

In parallel, the Honda CB 900 Bol d'Or has been developed of this type, there was also a displacement weaker version, the CB 750 F ( RC04 ) Bol d'Or with the engine of the CB 750 K ( RC01 ), by a modified exhaust system ( 4-2) now made ​​79 hp. These legitimate successor of the CB 750 was initially available only in Japan, Canada and the United States and derived from the sold only abroad top version CB 900 F Bol d'Or. In Japan itself, it was hard because of the license provisions to bring motorcycles with over 750 cc on the market. The term Bol d'Or was a reminiscence of the success of Honda at the Bol d'Or, the 24 -hour bike race in France.

In the early 1990s Honda again took a modern designed and on the market then quite successful CB 750 Four in the program, to tie in with the old glorious name: after a decade break, the third, fundamentally new version of a four -cylinder sports tourer. This version is called CB Seven Fifty and was built from 1992 to 2002.

On 23 October 1999 for the 30th anniversary of the in-line Four, Honda surprised at the Tokyo Motor Show the public with a study (prototype ) named CB Four, the optically in many things the old CB 750 Four was like, but did not go to series. The engine was in this study, however, a specimen with two overhead camshafts and DOHC in front were two disc brakes.

The Four of today's road image

Nowadays, in particular the machinery of the first series, the models K0 -K7 ( K8), as vintage motorcycles in good condition are evaluated at a multiple of their former original price. Models in their original condition, however, are rare, which is also because on the one hand, that the Fours were a " grateful " foundation for rebuilding and tuning measures; on the other hand were just the exhaust has always been prone to rust and expensive and for some years no longer available, so that a wide variety of 4- in-1 plants grown. For some time (around 2006) to the original 4-in -4 Exhaust available again. An accepted in vintage car circles reconstruction of Four is equipped with a second front disc brake. Since standard mounting points are available for the caliper, this conversion is easily doable.