lundi 11 janvier 2016

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Dreams of the Africa Twin


An all-new 'Honda-style' adventure bike created by an enthusiastic young team of engineers.

Debuting under the motto, 'True Adventure,' the new CRF1000L Africa Twin appears as a traditional Honda big off-roader for a new era. This all-new 'Big Off-Roader' package was created from scratch
by an enthusiastic team of development engineers who love off-road riding. Staying one step ahead
of everything else on the road, this uniquely 'Honda-style' off-road model embodies the true
Spirit of Adventure.

History

First released in 1988, the Africa Twin not only pioneered the 'Adventure Sports' genre, but also featured the long-term comfort of a touring bike while being at heart a big off-roader.

Honda's first-generation Africa Twin was released in 1988 as a large-displacement touring bike that played a central role in the creation of the Adventure Sports category. At the time, on-road super sports models were rapidly growing in popularity around the world, and the African Twin was conceptually very much the antithesis of those sports machines.

Its design roots could be found in the NXR750, the specially developed Honda Works rally machine that from 1986 took the title in the motorcycle division of the Paris-Dakar Rally (currently 'Dakar Rally') four years in a row in what is to this day regarded to be one of the most severe tests of man and equipment in the world. The technologies developed for this Honda factory racer were fed back directly into the development of the Africa Twin, making it a 'racer replica' of the famed off-road rally machine.

While market interest in large-displacement motorcycles produced in the late 1980s was largely focused on 'racer replica' super sports models, the Africa Twin's positioning as a touring bike with off-road styling was, in a word, unique. Moreover, as most off-road models were powered by small to midsized engines, the Africa Twin's large-displacement V-twin made it singularly extraordinary for its time.



Featuring distinctive off-road styling, the African Twin made its debut with a large-volume fuel tank, dual headlights and large integrated fairing. Its liquid-cooled 4-stroke 52° V-twin engine featured Honda's unique offset dual-pin crankshaft for smooth operation, a 3-valve head configuration for enhanced intake and exhaust efficiency, and dual spark plugs for improved combustion efficiency. As a road bike, the Africa Twin's highly reliable power unit also made it an excellent touring model for its time.

The African Twin's chassis was constructed on a highly rigid box-section double-cradle frame, and featured a large-volume 24-liter fuel tank that integrated in form with its wide-coverage fairing. Fitting an off-road styled model with such a large fairing gave this 'Paris-Dakar Replica' the look of the actual machines that had recently conquered the Paris-Dakar Rally. Further equipping it with dual headlights and a large aluminum engine bash plate, not to mention wide-coverage knuckleguards, rugged front fork bottom case covers and a spacious buckskin-textured seat, gave birth to a new Rally Replica genre of Dual Sport motorcycles that had never existed before.
In 1990, the Africa Twin's displacement was increased from 647cc to 742cc. It was also given a larger and taller windscreen, a larger-capacity battery, and brighter headlights, which further augmented its broad appeal as a full-scale Adventure Sports model. 1992 saw the adoption of a multi-function digital trip meter, which provided not only dual odometers and a trip countdown display function, but also a stopwatch. A full model change in 1993 further raised the Africa Twin's level of refinement, and extended its popularity as a full-sized Adventure Sports model well beyond the end of its production run in 2003.

A new area

Nearly 15 years have passed since the first Africa Twin ceased production. Heartfelt requests from Africa Twin fans around the world, coupled with the passion of Honda's own Africa Twin fans and off-road riding aficionados helped create this powerful new long-touring model with an appetite for venturing off the beaten path.

The Africa Twin, a legendary machine of which Honda has long been extremely proud, and a pioneer of the Adventure Tourer category of large-displacement dual sport motorcycles, is making its return. Impassioned requests from enthusiastic fans around the world have finally borne fruit nearly 15 years after production of its predecessor model came to an end.

The passion with which a small group of young engineers kept alive the dream of creating a new big off-roader, an Adventure Tourer, gradually expanded, resulting in the rebirth of the new Africa Twin.
The new African Twin they eagerly sought to create would maintain its predecessor's fundamental concepts while being infused with the best of over 25 years of accumulated state-of-the-art technology. A full-cowl touring model powered by a large-displacement engine that is also capable of freely venturing well off the well-travelled road — this concept has now been revived and given new form. A well-rounded machine that expert development engineers finished with the passions of young engineers in mind. Completed with a wide range of riders in mind, from relative novices to adventure experts, and from touring aficionados to off-road fans — This is the new Africa Twin.
This new Adventure Tourer is powered by a newly developed liquid-cooled SOHC Unicam 4-valve parallel-twin engine. Although the original Africa Twin was known for its V-twin engine, one reason that the new Twin does not employ the same design configuration is that an engine type that best matched the machine's new compact proportions needed to be selected. The engine's forward-canted parallel-twin layout helps realize a shorter longitudinal length than possible with V configurations, further making it possible to shorten the overall length of the chassis and its wheelbase. Also, relative to the V engine, this compact twin further offers the merits of centralized mass for more responsive handling, and a slimmer shape in the seat area.

The 998cc engine's output of 70kW was determined to be more than sufficient for both long touring and off-road adventures. This also allowed the chassis to be designed for lighter weight and more compact proportions, as well as offering easy control. Further, its 270-degree offset crankshaft provides excellent traction from low in its rev range, and strong, responsive acceleration, delivering up a pulsating engine feel that only an irregular combustion interval can provide.
Additionally, the Honda Selectable Torque Control System (HSTC) is offered as standard equipment. This electronic control system controls the amount of engine torque reaching the rear wheel in order to minimize slippage and wheel spin, and maintain an appropriate posture while riding. This control system can also be manually disabled during sport riding, and can be said to be symbolic of the importance attached to the Africa Twin's off-road riding capabilities. Moreover, the Twin's switchable Antilock Brake System (ABS) makes it possible to disable only the rear tire's ABS function, providing an extra degree of freedom and flexibility during off-road rides. In other words, the new Africa Twin is a riding machine that attaches the utmost importance to total mobility during off-road travels.

Another notable feature is a version being released equipped with Honda's unique Dual Clutch Transmission (DCT). Till now, DCT had been designed to provide greater comfort and ease during long rides. However, besides its obvious benefits during high-speed touring, it was specially adapted to the Africa Twin with off-road use in mind. Because of this, a 'G Switch' was added, which enables the capacity of the clutch to more closely conform with engine torque output whenever momentary increases in traction are needed when travelling off-road. This can also be disabled whenever a more gentle application of the clutch at low revs is preferred, enabling the rider to gain a more visceral feeling of the engine's power, depending on riding conditions. Additionally, a hill climb/descent detection function has also been added, allowing appropriate speed adjustments when travelling up and down steep hills.



Although the Africa Twin's vehicle weight is virtually the same as that of its famed predecessor, in the quest for more effectively centralized mass, weight distribution was calculated to provide more responsive controllability, better enabling it to confidently venture off road, even though it is at its heart it is a large-displacement touring model.

The Africa Twin's styling was designed with an emphasis on providing a slim and lightweight feel while offering a sense of substantial volume. Its bodywork features an integrated form free of bulging protrusions that helps minimize damage in the event of a fall while riding over rough roads.
A young team of development engineers contemplated what an Adventure Tourer of the future should be, and succeeded in making the new Africa Twin a motorcycle that tempts riders to explore new roads and lands off the beaten path, whether riding tandem or fully loaded with touring luggage.
Adventure does not necessarily mean only charging out across undeveloped lands or deserts. Venturing off onto an unexplored side road for the first time can also be an adventure - this machine enables its riders to actually experience such feelings. Welcome to the new Africa Twin, the ideal Adventure Tourer for a new age.

Technical points

The new Africa Twin delivers nearly 1.5-times the power output of its predecessor, the original Africa Twin, while maintaining the same size and proportions. Fully equipped with features one would expect of a 'True Adventure' model for the new era, its beautifully designed new engine and peerless handling enable riders to enjoy both long-term comfort and athletic agility.

The more one comes to know about the new Africa Twin, the more one can come to understand that it is a motorcycle featuring two 'exceptionalities.'
One is that it features superb off-road performance, although it is fundamentally a large-displacement touring bike, and the other is that it powered by a large-displacement engine in spite of it being an off-road bike.

Usually, off-road motorcycles become harder to control as their engine displacement increases, and comfortable touring bikes often require a certain increased degree of displacement and weight.
The Africa Twin was created with these points in mind.



Unlike the venerable V-twin engine that most people associate with the original Africa Twin, the new Africa Twin's engine features a compact parallel-twin configuration. To improve controllability and handling ease when riding off-road, the distance between the rider and the front wheel needed to be shortened. It is for this reason that the parallel-twin engine, which is shorter in longitudinal length than the V-twin, was selected. The adoption of the parallel-twin engine also offers additional merits in that it allows the center of gravity and mass of the engine to be positioned farther forward than is possible in the case of the V-twin, leading to an optimal front load distribution.
On the other hand, off-road riding requires the ability to freely change one's riding position, and so the rear end of the fuel tank where it integrates with the riding position and around the seat rails needs to be made as narrow as possible. Although the rear cylinder of a typical V-twin engine may be located between the rider's thighs when ridden, if a parallel-twin engine is used, that area can be put to more efficient use as a space for auxiliary equipment, etc. Because of this merit (i.e. the ability of providing more centralized mass by positioning the heaviest components, such as the battery, in that space), the parallel-twin configuration proved to be essential. For this reason, it can be said that Honda gave priority to the design of the engine without tying itself to the conventional image of the Africa Twin.

Furthermore, as nearly 15 years had passed since the original Africa Twin ended production, technologies that made great advances in the interim were also selected for use in the new model. These include an ABS version, not to mention standard-equipped HSTC (Honda Selectable Torque Control). Honda's advanced DCT (Dual Clutch Transmission) technology also proved to be effective for enhancing the off-road performance of this large-displacement touring bike.
The new Africa Twin is poised show us the brillant new world that lies beyond the door to Adventure.

Package

The new Africa Twin maintains essentially the same body size and weight as its predecessor, however power output has been increased by fully 1.5 times. It is also 43kg lighter in weight than the VFR1200X, and 13kg lighter than the VFR800X. Moreover, its 70kW power output is comparable to the 74kW put out by the CB1300 Series, enabling riders to fully enjoy its high power and torque, which rumbles up from deep down in its wide rev range, making the new Africa Twin a remarkably easy to control riding machine.

Furthermore, the Africa Twin also employs many technologies first introduced on the CRF450 Rally that recently competed in the Dakar Rally, such as an LED headlight that has proven to be highly effective for long touring, a multi-function meter and adjustable front and rear suspensions. These technologies combine with versions available with switch-selectable DCT and ABS to make the Africa Twin eminently suitable for a new era of motorcycling enjoyment.


Engine

The Africa Twin's newly-designed parallel-twin engine employs a SOHC Unicam valve train to actuate the 4 valves in each combustion chamber. The engine's compact configuration features an external design that doesn't feel as if it has a large 1,000cc displacement. Power output characteristics offer excellent response, while its 270-degree offset crankshaft contributes to the engine's enhanced torque and traction. Providing a pleasant pulsating feel, this engine offers excellent controllability, as if the throttle and rear tire were directly linked to each other. Further, as might be expected of a touring model, its engine provides strong torque from anywhere in its wide rev range, and features dual balancers for reduced primary vibration.

Handling

While the Africa Twin is a large-displacement touring model, its total weight does not exceed 232kg (standard type: 228kg). Its chassis configuration has been finished to provide good controllability in off-road riding. Additionally, both front and rear overhangs are kept to a minimum, and the battery and other heavy components have been centrally positioned in the area nearest the motorcycle's center of gravity for supremely agile handling.
Furthermore, the compact engine also makes possible a ground clearance height of 250mm, while also improving the Africa Twin's stellar off-road performance.
Turning Capability
The Africa Twin's 43 degree steering angle makes possible a minimum turning radius of 2.6m, which represents the top level in the adventure class. This feature also leads to improvements in turning ability not only when riding, but also when parking or moving the bike.
Two different seat heights (870mm and 850mm) can be selected by changing the seat's mounting position. Further, a high seat and a low seat are also made available as optional equipment, with the former enabling the seat height to be raised by 30mm and the latter to lower the seat height by 30mm. This extends the highest seating position to up to 900mm and the lowest position down to 820mm, thus making it possible to adjust the seating position to best match a wide range of rider sizes.



Bodywork

As one would expect from a world-leading adventure model, the new Africa Twin features heavy-duty construction with bodywork and engine designed to be effectively free of protrusions in order to minimize the potential for chassis damage. The goal of this design is minimizing injury and damage that might occur if the motorcycle should accidentally fall when traveling off-road, etc. Moreover, some versions will also be standard-equipped with a large aluminum skidplate mounted under the engine.

And by minimizing the number of body panel parts used in the pursuit of functional beauty, a body construction that minimizes damage was realized.
HSTC (Honda Selectable Torque Control) System
The new Africa Twin also comes standard-equipped with the Honda Selectable Torque Control System, which controls the engine's torque output by detecting differences in the slip ratio between front and rear wheels. When the rear tire loses traction on a slippery road surface, this system causes the control system to instantly kick in and suppress the torque generated by the engine by controlling fuel injection to inhibit rear tire slip. The amount of torque control can be selected in three steps, and the torque control system can also be disabled.



ABS-Equipped Version

The Africa Twin will also be made available in a version equipped with ABS (Antilock Brake System) and featuring mode switching capability. Called 'Adaptive Rear ABS Cancelling,' this system disables the ABS at the rear wheel when set to the OFF position. This feature contributes to off-road riding ease by allowing separate use of the front and rear brakes, allowing the machine to be controlled by only the rider's operation.

DCT-Equipped Version

For the first time ever in an off-road model, the Africa Twin will also be made available in a version equipped with Honda's innovative DCT (Dual Clutch Transmission) motorcycle technology. The system features both a Manual mode and two different automatic gear change modes: 'D' mode enables comfortable cruising and low fuel consumption, while 'S' mode offers a more sporty gear shift patterns (adjustable in 3 steps).

The system has also been equipped with a new 'G Switch' that allows the Africa Twin to control clutch application and power fluctuations at low revs, depending on riding conditions, for a perceptible increase in tractable power. Turning off the switch makes the power delivery more gentle, bringing an extra level of stability to the machine's behavior.

The Africa Twin's DCT was designed with the assumption that off-road riders needing to concentrate on the road or terrain ahead, not to mention their own body control, would greatly benefit from being relieved of the distraction of gear changes, making it possible to more fully enjoy the experience of off-road riding.

Development Story

A touring bike that makes long-distance travels pleasant and comfortable, while making it possible to detour onto dirt roads or mountain trails in big-bike off-road style — The intense enthusiasm of Honda's off-road riding devotees leads to the realization of a new Africa Twin

What I can do is show you the 'Door to Adventure'
Many dangers lie beyond this door,
But only you can open it.
I can take you there, if you wish.
- Thierry Sabine -


A Dream Named 'Adventure'

As Seen by a Young Team of Engineers

The 'adventure' spoken of by Thierry Sabine, founder of the Paris-Dakar Rally, has many different meanings, but motorcycles are always found in close proximity to this word 'Adventure.' "Adventure? Yes, I love it. Doesn't every boy share a love of it? However, the adventure I'm talking about is not only one of trekking to the ends of the earth or visiting unexplored regions. Instead, adventure could entail such simple things as riding your bike off a well-travelled highway onto a small side road for the first time, or over a bumpy road," says Yutaka Yamakura of Honda's Motorcycle R&D Center, who was put in charge of the Africa Twin's chassis and bodywork design. He talks cheerfully, with a big smile on his face, perhaps because he's imagining riding a motorcycle, especially off-road. As a matter of fact, Yamakura is a 'key man' who played a vital role in the development of the new Africa Twin from its initial stage of development, creating its concept and determining its direction based on its predecessor model.



Back in high school, Yamakura had been fascinated by dreams of 'adventure,' as described by Paris-Dakar Rally founder Thierry Sabine.

Yamakura — "When I was in junior high school, the Paris-Dakar Rally was just starting to be televised. I watched that program many times, and the images I saw were absolutely riveting. There were many TV programs about the Paris-Dakar Rally, but mostly they focused on the cars in the competition. Instead, what I really wanted to see were the bikes racing in the 'motocross division.'
"At first I was amazed to see them racing at top speed over such harsh terrain, thinking, "Wow! How can they race in a place like that on a bike?!" Soon, I began taking a deeper interest in the motorcycles themselves, and eventually learned about a bike called the NXR. It was a Honda Works machine, solely intended for racing in the Paris-Dakar Rally. As time went on, I became infatuated with the big off-road bikes, and even rode around on an Africa Twin that I'd bought myself when I was a university student. That was one of the reasons why I chose Honda as the company I wanted to work for."

Wanting to Create a New Africa Twin
The Africa Twin was still in the Honda lineup when Yamakura joined the company. Holding out hope of someday making a new Africa Twin, and dreaming of taking charge of its development, Yamakura continuously talked about creating a new Africa Twin within the company. However, production of the Africa Twin ended only a few short years after he joined Honda.
Yamakura — "The end of the Africa Twin's production left Honda with no large-displacement dual sport models in its lineup. From then on, I agitated for developing a new Africa Twin every chance I got."

As a result of this personal campaign, when the development project for a new dual sport model finally began, Yamakura was selected as one of the team members. His chance had come at long last.

Riding Enduros on the Africa Twin.

Waves of Enthusiasm Begin to Grow.




As Yamakura speaks animatedly about the project, Akihiro Iida smiles quietly, like an older brother. Iida has long been deeply involved in engine development at Honda's Motorcycle R&D Center.

Iida — "I was really eager to go racing when I first joined Honda. Frankly, what I really wanted to get into was F1. Although I'd ridden motorcycles back in my school days, I didn't have any special preference for them. When I first joined the company, I was assigned to the motorcycle division, but I soon asked to be transferred to HRC (Honda Racing Corporation) because I still wanted to do something in racing. I was surprised and delighted when the company granted me that wish. Since then, I've been put in charge of the development of many different categories of engines."
At HRC, Iida took charge of the design of such engines as air-cooled singles and advanced 4-stroke engines for Trials bikes, as well as race engines for the Suzuka 8 Hours World Endurance Championship and Moto GP machines. Having played a central engineering role in these creations, Iida was selected to join the development team for the new Africa Twin.

Iida — "I have no idea why I was assigned to the Africa Twin development team. When I joined the team, I had so little knowledge of what the Africa Twin was that I had to ask, 'Africa Twin? Isn't that some kind of big off-road model?'"

Yamakura explains the reason. "The team needed an engine design specialist who is capable of designing small and lightweight engines from scratch."

As the leader in charge of the new machine's overall chassis and body design, Yamakura called on Iida as an expert in engine development. Besides Iida, other 'Big Off-Road' enthusiasts were also recruited from within the company to focus their efforts on researching structural strength and riding stability issues. The new project started off with discussions about what the Africa Twin was, and what the new Africa Twin should be.



Next, as a representative of the development team, Yamakura started riding his own Africa Twin in the company's in-house enduro races. Competing against other smaller displacement models such as the XR100, CRF250L and XR250, his big Africa Twin finished the races in style, impressively showing off its riding ease and confident control.
Yamakura — "I told the other team members I'd selected that, 'This is the sort of bike we want to make. Isn't it great?' I'd like to think they all came away with a better understanding of the Africa Twin's many great features. I explained, 'Let's recreate this using today's technologies! If we do it now, we can make a new Africa Twin entirely from scratch, with no need to think about carrying over existing components.'"

Yamakura's enthusiasm gradually began to spread to the others around him.



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