On the move: BMW R 27, Honda CB 72

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On the move: BMW R 27, Honda CB 72
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On the move: BMW R 27, Honda CB 72

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Almost everyone has already experienced one thing: a big anniversary. Two who made history celebrate their 50th birthday together.

A.When you come to a class reunion with a certain amount of curiosity, you soon realize: one person has remained young, the other has always looked old; one has achieved something, another less so. Countless stories about the now and stories about the do-you-remember? bring back memories. This is where two people meet who saw the light of day in the same place at the same time. But the producers could hardly have been more unequal: on the one hand, urban Bavarian traditionalists from Munich, on the other hand, young Japanese entrepreneurs with headquarters in Tokyo.

The delivery room was in Frankfurt and was called IFMA. There, in the fall of 1960, visitors saw the BMW R 27 and the Honda Dream Super Sport 250, internal code CB 72, for the first time. The common features were the numbers 2 and 7 of the model names, two wheels and a displacement of 247 cm³. Other than that, the two motorcycles went different paths in every respect. These were difficult: the motorcycle market had bottomed out in 1960. The German motorcycle industry was only represented with a few models in the once flourishing 250cc class.


The classic BMW R 27 in traditional paintwork. Full swing chassis and cardan drive arouse tourist ambitions.

In the BMW program, the single cylinder played the role of the stepchild; the company much preferred to see itself represented by its boxer engines. Nevertheless, the new one had experienced massive obstetrics: Compared to the outwardly almost identical predecessor R 26 with full swing chassis, the fathers of the R 27 had a lot of hands. The governor and interrupter had moved from the crankshaft to the camshaft.

The biggest change can only be seen on closer inspection: the mounting of the motor in rubber elements. The nominal power, which has increased from 15 to 18 HP, is only evident from the papers. Even the family trees of the two differed considerably. The genes of the BMW ohv single-cylinder with longitudinal crankshaft and cardan shaft went back to the R 39 from 1925, which had the same design features.


Narrow fenders, the flat seat and the inclined cylinders characterize the sporty appearance of the Honda CB 71.

The family tree of Honda is much smaller: The C 70, published in 1957, served as a template for the 250 twin-cylinder of the CB 72. Like its successor models C 71 and C 72, it had a pressed steel frame and baroque curved fenders, which like the fork with a short swing arm were strong remembered the NSU Max. Honda largely adopted the two-cylinder with overhead camshaft for the CB 72, but equipped it with two carburettors and a 180-degree crankshaft, so it became a counter-rotor.

The rest of the two-wheeler got a radically new look. The backbone frame with telescopic fork corresponded to the trend of the Honda racing machines that were so successful at the time. Narrow mudguards and large drum brakes exuded the aura of GP racing, which was also evident in every one of the numerous Honda advertisements. Although a two-cylinder with an overhead camshaft was nothing new, the motorcycle scene had hardly seen a sportier, mass-produced vehicle until 1960. The CB 72 even had a rev counter as standard. His scale penetrated into regions that until then had been utopian for production motorcycles. Markings on the speedometer scale on the R served the same purpose. So the BMW fell back on 35-year-old technology and didn’t even try to be innovative.

The differences in detail


Honda’s two-cylinder in-line engine was known for high speeds.

Honda set new key design data that generations of two-cylinder engines should adopt – not only at Honda: In addition to the CB successors with 250, 350 and 450 cm³, the competing models from Kawasaki, Suzuki and Yamaha also adopted the construction principle of the counter-rotating twin . By balancing the first-order inertia forces, this design enabled such high speeds in series for the first time without the motorcycle having pulverized itself in violent vibrations.

The first Honda test machine elicited Ernst "glob" Leverkus’ euphoric reflections: “Since the appearance of Japanese motorcycles on the European market, the Honda CB 72 has been the most discussed model from the Far East. Today it is one of the motorcycles whose names the enthusiasts use with a special undertone of admiration. If a 250 cc machine is still for sale with us, it seems to be this CB 72. It’s not just this fantastic engine output of 24 to 25 hp, but the really sporty look and the details of a real sports machine. “

Today, 50 years later, the former opponents shine in the southern French winter sun and repeatedly catch interested glances from passers-by. Even people who remember the 1960s well hardly believe that the BMW and the Honda are from the same year. The driver of an Alfa Romeo Giulia even turns around to marvel at the motorcycles. He dates the R 27 to the mid-50s and the CB 72 to the end of the 60s. The condition of the vehicles can hardly influence his judgment, both the BMW from Ulis motorcycle shop in Frankfurt and the Honda from Garage 48 in Hockenheim are extremely well maintained and almost completely original. Only the BMW wears chrome-plated wheel covers instead of the silver one, a contemporary modification.


Two motorcycles could hardly be more different: Honda CB 72 and BMW R 27.

In fact, the Honda CB 72 is even older: It was built in 1961. The steel rims and the air filter, on the other hand, indicate that our R 27 is a modeled 1963 model. The traditional black of the BMW, white decorative lines on the tank and fenders as well as the nostalgic-looking saddle create a clear contrast to the Japanese: the Honda is in blue, silver and chrome and looks much more delicate and sporty with the flat double bench seat.

Touring riders versus sports riders: two worldviews collide


When the BMW kicks in, the engine moves quite violently in its elastic mounting in the chassis.

The starting procedures in winter temperatures could hardly be more different: after dabbing at the float chamber and a few kicks on the kick starter, the BMW starts with violent movements of the rubber-mounted engine and soon bubbles in a calming tone. The Honda also has a kick starter, but the driver doesn’t have to try it: he casually flips the choke lever on the carburettors and presses the button. The starter spontaneously wakes up the twin and makes the BMW and Honda drivers shudder: one person perceives the arrhythmic two-cylinder sound to be unusual, perhaps even suspecting a defect. For the other, the hard double punch sounds like the soundtrack from a Grand Prix track.

Starting up, whether with a kick or electric starter, triggered a war of faith at the time. The purist saw the sissy who couldn’t bring the motorcycle to life with one kick, the progressive looked down on the yesterday. Karl Reese commented skeptically on his first encounter with the CB 72 in Das MOTORRAD: “How to build a starter on a super sports machine – so know, no! Why so much additional complexity? A motorcycle has to be easy! ”Times are changing.

The seating position is as different as the look: On the BMW, the driver sits enthroned with an upright upper body, his hands laid loosely on the pleasantly narrow, cranked handlebars. On the Honda, the driver sits more bent over. His hands stretch towards the even narrower and lower handlebars, resulting in a much sportier seating position. Comfortable here, gathered there – two-wheeled worldviews collide again: touring riders versus sports riders. Then the moment of truth strikes. The BMW driver lets the smooth clutch come and starts without nervous revs. The gearshift mark on the speedometer sheet is reached after a short time, and the gears need to be sorted at short intervals. But calm is required; the circuit requires power and time over longer distances.

From today’s perspective, the large centrifugal masses of the single cylinder and the relatively fast-running transmission require a short pause with every shift until the next gear engages properly. Even the often criticized transmissions of modern boxers, on the other hand, shift as smooth as butter. In every gear, the single cylinder pulls up evenly, almost sedately, and hums its monotonous song. There is serenity, people who are in a hurry or even hectic are less likely to make friends with the BMW. In the last gear, fourth, the R 27 takes plenty of time to break the 100 km / h mark. Only a relaxed driver can enjoy the fun in the BMW and has enough time to contemplate the landscape.


In the Honda instrument cluster, the pointers move in opposite directions.

The Honda driver perceives the world very differently. The clutch requires a strong hand, just sporty. The CB 72 requires significantly more speed to start, but then every sports driver’s pulse beats faster: With the hard, highly impressive two-cylinder sound in his ear, he almost thinks he is in a Grand Prix run. The tachometer needle clicks up in sync with the growling staccato from the chrome-plated silencers. The crisp four-speed transmission can be switched through quickly and precisely, and the desire for a fifth arises. Nominally, there is only 6 hp between the BMW and the Honda, but it feels like far, far more. This is exactly how we imagined a racing motorcycle when we were young! The counter-runner tingles slightly in the handlebar ends and footpegs in the range of 6000 to 7000 rpm. But the BMW stew also transmits vibrations to the chassis as the engine speed increases. The different solution to mass balancing remains philosophy.

How can the two machines be driven??


Getting used to: the cardan drive of the BMW R 27 creates the familiar elevator effect. The chassis is stable and taut.

After the heated discussion about the engines – the BMW driver etches over the barrel organ, the Honda driver gossips about the horse – the chassis is up for debate. Here the BMW surprises with a balanced vote and refutes the fairy tale of the rocking chair. Even second-order roads in the southern French hinterland are stable and tight, but not uncomfortable. It takes tight bends very easily. The distinctive elevator effect alone takes getting used to, but thanks to the manageable performance it is kept within limits: When accelerating, the cardan pushes the rear upwards; when braking, the fork rebounds because the front drum is supported on the long swing arm. The brake requires a lot of force, but then decelerates noticeably.

Now the Honda has to face the suspension discussion that has been going on for years and promptly uses the cliche: It just doesn’t offer the balanced set-up of BMW. The fork is sensitive, but the struts are too soft and underdamped. The tail swings on bumps and stimulates slight unrest in curves. Such pendulum phenomena are never unsettling, but allow BMW drivers to triumph. Even Klacks complained about this weakness, and a brand new CB 72 was available to him.


The rear duplex drum of the Honda CB 72 actively supports the front counterpart.

The Honda can’t quite keep up with the BMW in terms of handiness either. Compared to today’s motorcycles, it turns like a light motorcycle, but requires a little more effort on the handlebars. This is all the more surprising because the Japanese is the more delicate motorcycle, stands on narrower tires and, with a full tank of 162 kilograms, weighs 12 less than the BMW. In return, the two duplex brakes in the front and rear wheels of the Honda are clearly superior to the BMW Simplex drums, with one exception: after the pads have been put in place, the CB 72 needs a few meters to build up its full deceleration power, which is then stable holds. When both brakes are applied, the significantly higher design effort of the Honda is reflected in a positive way.

The impressions of the two classics could hardly be more different. On the one hand, the BMW demands composure from the driver and scores with a good chassis. On the other hand, the Honda appeals to ambitious sports drivers. Honda liked and extensively cultivated this brand image. The advertising campaign for the CB 72 started relatively late, but when Honda installed an official importer in Hamburg at the beginning of 1962, he aggressively advertised the CB 72 with sporty motifs and tried to achieve the success of the factory four-cylinder in the world championship.


The two classics, the BMW R 27 and Honda CB 72, are still a lot of fun on the road today.

This depiction brought the Honda CB 72 into the consciousness of motorcyclists: It was obvious that a type of motorcycle had emerged that was preparing to usher in a new era. In doing so, Honda calculated a price for the elaborate two-cylinder engine which, at 2675 marks, was within reach of the BMW R 27, which cost 2330 marks. The BMW marketing strategists did not advertise the R 27, mentioning it only once in Das MOTORRAD – and then in connection with the boxer models. The other Japanese manufacturers, who certainly already exported motorcycles to Germany, hardly advertised their products either. So Honda in particular remained present in public.

In 1960 there was no telling what would become of the two adversaries. Today, at the 50-year-olds meeting, the different development of the two can be summed up perfectly: The Honda CB 72 initiated the image of sporty and technically highly sophisticated Japanese motorcycles in Germany and made it socially acceptable in a stroke of a hand. The BMW R 27 heralded the farewell to a decades-old BMW single-cylinder tradition. It was not until 1993 that the Bavarians built a single-cylinder motorcycle again – in Italy and with an engine from Austria.

Technical data of the BMW R 27 and the Honda CB 72

  BMW R 27
Honda CB 72
 engine    
 design type

 Air-cooled single cylinder-

 Four stroke engine, one below-

 lying camshaft,

 two valves, bumpers,

 rocker arm

 Air-cooled two-

 cylinder four-stroke engine,

 an overhead

 Camshaft, two valves

 per cylinder, rocker arm

 drilling  68 mm  54 mm  Hub  68 mm  54mm  Displacement  247 cc  247 cc  compression  8.2: 1  9.5: 1  power  18 hp at 7400 rpm  24 hp at 9000 rpm  Mixture preparation

 Round slide carburetor,

 Bing 1/26/68, 26 mm

 2 round slide carburetors,

 Keihin PW 22, 22 mm

 Electrical system  starter  Kickstarter  Kick / electric starter  battery  6V / 9Ah  12V / 9Ah  ignition

 Battery / coil ignition,

 contact controlled

 Battery / coil ignition,

 contact controlled

 alternator  6V / 90W  12V / 60W  Power transmission  coupling

 Single slices-

 Dry clutch

 Multi-panes-

 Oil bath clutch

 transmission

 Four-speed,

 claw-switched

 Four-speed,

 claw-switched

 Primary drive  –  Gears  Secondary drive  Cardan  Chain  landing gear  Frame type

 Double loop frame

 made of tubular steel

 Backbone frame

 made of tubular steel

 Front wheel guide  Two-arm long swing arm  Telescopic fork  Rear wheel guide

 Two-arm swing arm out

 Steel pipe, two

 Struts 

 Two-arm swing arm out 

 Steel pipe, two

 Struts

 bikes  Wire spoke wheels  Wire spoke wheels  Front tires  3.25 – 18  2.75 – 18  Rear tire  3.25 – 18  3.00 – 18  Front brake

 Simplex drum brake

 160 mm diameter

 Duplex drum brake

 220 mm diameter

 rear brake

 Simplex drum brake

 160 mm diameter

 Duplex drum brake

 220 mm diameter

 mass and weight  wheelbase  1360 mm  1295 mm  Weight  174 kg  162 kg  Tank capacity  15 liters  14 liters  Performance  Top speed  125 km / h  155 km / h  price  2330 Mark (1962)  2675 Mark (1962)  Manufacturer

 BMW AG, Munich,

 Germany

 Honda Motor Co.,

 Tokyo, Japan

     

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