Motorcyles that shaped eras
27 May 2021
Source: Photo by Leon Seierlein on Unsplash
In 1968, Honda presented its CB 750 Four for the first time - and it proved to be a surprise success that had a profound influence on the motorcycle landscape in Germany. From then on, two-wheelers turned into recreational vehicles enjoyed with relish. From the mid-1950s onwards, no one in Germany wanted to have motorcycles anymore. Those who could afford it had switched to a car. Within twelve years, from 1956 to 1968, the number of motorcycles dropped to a tenth, from 2.5 million to 250,000 machines. It seemed only a matter of time before the last motorcycle would rust in some garage.
And now this: four cylinders, 67 HP, Vmax supposedly 190, disc brake, four shiny chrome-plated exhaust pipes - a sight to behold, even though Honda had only been around since 1948. In 1958, the company celebrated its ten-millionth motorcycle and achieved an important milestone: the Honda Super Cub model made its debut, the "Cheap Urban Bike", an affordable vehicle for mass motorization. To date, 60 million units have rolled off the assembly line; it is the most frequently built motor vehicle in the world. But the CB 750 developed a different dynamic, a new form of explosive power. Because it inspired dreams, sparked the imagination and awakened desire. It became the successful savior of the dormant motorcycle scene worldwide.
At the end of the 1960s, Honda had achieved numerous motor sport successes and had long since acquired a reputation as a mass manufacturer. It was high time for a larger capacity motorcycle. In October 1968, the brand-new Honda CB 750 Four caused a sensation at the Tokyo Motorshow and delighted the public and experts alike. The CB 750 Four is rightly considered the first superbike in motorcycle history. With its four-cylinder in-line engine and standard details that were previously only available as an extra - if at all - it triggered a trend-setting change in the construction of large motorcycles.
The successful concept of the CB 750 Four is as simple as it is ingenious: combining power with sportiness and true all-rounder qualities in just one motorcycle. No wonder that its inspired look and charisma electrifies everyone - until today. In 1969, the Honda CB 750 Four heralded a new era of performance, smoothness and reliability in the motorcycle world and dominated its segment in the 1970s, helping Honda establish a leading position among motorcycle manufacturers. And that is why the Honda CB 750 Four is THE motorcycle of the century for us!
Silky smooth engine of the CB 750 Four
With the Honda CB 750 Four, Honda created the nucleus of all subsequent superbike models: with four cylinders, four strokes, four carburetors and a beautiful four-in-four exhaust system (four-valve technology followed later), it set new standards for superbike models. For the first time in a series production motorcycle, Honda installed a hydraulic disc brake at the front. At that time, the electric starter was almost a common feature - at least for Honda.
The air-cooled and transversely mounted four-cylinder four-stroke in-line engine of the Honda CB 750 Four had a displacement of 736 cc (bore: 63 mm, stroke: 61 mm), produced an incredible 67 hp at 8,000 rpm and 60 Nm torque at 7,000 rpm. The fuel supply was provided by 4 Keihin slide carburetors, each with 28 mm passage. There was an overhead chain-driven camshaft (SOHC) and two valves per cylinder, which were opened by rocker arms with coil springs. The primary drive is via two parallel single roller chains.
Yamaha XV 535 Virago: Absolute favorite of the Germans with 51,621 models sold
It was as if an alien had landed 40 years ago. What progress: In MOTORRAD 15/1968, the editors had still celebrated two-thirds more power and performance within a ten-year period: "In 1958, a four-stroke engine with 18 hp from 250 cm3 was considered absolutely sporty, meaning 72 hp/liter displacement. In 1968, the modern Japanese high-performance 250s offer 30 hp as in 120 hp/liter capacity". Now the 750 was said to have three times the displacement and more than twice the power. The world was no longer the same.
"I did my driving lessons on one of these," is probably the sentence that is said about the XV 535 most often. Low, agile, and straightforward. Robust and low-maintenance with an inconspicuous shaft - that's what made the XV 535 the entry level chopper par excellence. Even though it was smiled at by many, it had a lot to offer besides the low seat height, such as the boldly curved exhaust system and an elastic V2. But it was not a bike to show off. Rumbling sound, powerful punch, or even bigger tires was not its thing. But if you were looking for a reliable companion for stress-free and carefree riding, this bike and its beautiful V2 were the right choice. And those qualities not only convinced driving schools, but ultimately also around 57,000 buyers.
It featured a minimalist structure, half chopper, half everyday bike - and a pleasing V2 engine, openly displayed, crowned by a drop tank, rolling through life on spoked wheels. A recipe for success, which in the days of the German class 1b driver's license was available in a lamblike 27 HP version and later upgraded to 34 HP. Because it never leaves you scared even in its most powerful version with 46 HP, because the low maintenance gimbal avoids oil-smeared fingers and because the low seat height accommodates even lightweight women, the XV simply had to become the darling of many occasional drivers. Another benefit: the chopper frees the rider from competitive thinking. Chopper riders have time, can wear fringed jacket and jeans, no one has to prove how fast they can turn corners. XV-535 drivers have it easy - and a bit difficult at the same time.
Because where are the unmistakable features? They can be found in the catalogs of the accessory suppliers. Turning the XV into an Indian? No problem. Even with a nostalgic knight fork, if you like. And how does the Yamaha mutate into a Harley imitation? With the custom kit provided by the company. But a bestseller always has to have inner values, so let's not forgot those: endurance, efficiency, and robustness. The XV has all these qualities, as the long-distance test in 1990 proved when the small chopper had been on the market for two years. And twelve more were to follow, sold 51621 times so far this year - which makes it the frontunner of the true evergreens.
BMW R 32
The R 32 was practically the reason for the success of the BMW car brand. After all, this was their first motorcycle, presented for the first time in 1923. The engine produced 6.3 HP and accelerated the R 32 to almost 100 kilometers per hour. In addition to being driven on the road, the motorcycle was used for racing as well. For years, the R 32 and R 39 remained the manufacturer's driving force. The R32 was the first in-house development of the Munich-based company and is therefore rightfully called the first real BMW motorcycle. This model already has two design features that were to remain characteristic of BMW motorcycles - the shaft drive and the boxer engine with the two opposite cylinders. A total of 3,100 models of the R32 were manufactured entirely by hand. With the transverse boxer engine, the Cardan drive and the torsionally stiff tubular frame, the designer Max Friz created a masterpiece.
No component of the R 32 was new in itself, but the composition set standards and provided numerous benefits that made the concept a milestone for BMW and motorcycle history. Unlike its predecessor Helios and the manufacturers Douglas and D-Rad, the boxer engine was installed longitudinally, i.e. the crankshaft axis was positioned in the direction of travel. This resulted in an excellent cooling of the cylinders and the critical area of the exhaust valves. The very flat and, due to its installation position, also short engine meant that the center of gravity was low, which was advantageous for the driving characteristics. Due to the directly flanged transmission, the flywheel could be combined with the dry clutch. Direct power transmission between crankshaft and gearbox was made possible without gear wheels or chains. The driveshaft to the rear wheel was, in contrast to the chain or belt drives of the time, almost completely eliminated the need for maintenance and cleaning.
With this motorcycle, BMW created the modular principle for future production series. Chassis and transmission with the basic engine were largely identical in construction; the differentiation for the cubic capacity classes with 500 cm³, 600 cm³ and 750 cm³ and for sports and touring models was achieved by modified cylinder bores, crankshafts and head- or side-controlled cylinder heads and cylinders. As early as the autumn of 1923, BMW presented its new motorcycle model at the Berlin Motor Show amidst 132 other manufacturers, a quite great number of competitors. The danger of going under without a sound was palpable. But Max Friz, the ingenious designer who had thought about a motorcycle for the first time in his life, proved his class once again, surprising the experts. They no longer saw a motorized bicycle here, but a product that had been designed independently and from scratch.
The R 32 stood out for its unusual smooth surface and its innovative frame construction with two steel tube loops. Besides, the low installation position of the engine ensured excellent road holding, and the deep black paintwork and the white decorative lines made it look high-class. After the end of the inflationary monetary devaluation, a BMW motorcycle cost 2,200 marks. Although it was one of the most expensive models on the market, it sold extremely well. This was due not only to its trend-setting construction but also to its reliability and material quality. Here, the expertise of a manufacturer whose customers once flew at dizzy heights and could not just pull over for a quick stop to tend to a stuttering engine proved its worth. In addition, the knowledge of new light metals that were used for the pistons stood the test of time and set new standards even in the smallest details. And the success took its course.
It was soon to be followed by sensational achievements in motorsports - at the time a particularly sales-boosting type of promotion. Even before the actual presentation in Berlin, Max Friz had already demonstrated the reliability of his invention in a comparative sports drive during the "Drive through Bavaria's mountains". Rudolf Schleicher then became the engineer who developed the R 32 into a sports vehicle. 1924 not only saw the first wins, but also the first German championship title for BMW. However, it was only the beginning of an unprecedented series of victories that began with the R 32 and elevated BMW to a major vehicle manufacturer.