BMW K1200S

Have bike, will travel... I reckon Joburg to Cape Town would be a pleasure on this baby.

What a great looking bike, performing as good (if not better) as it looks.

Sport is about being number one - on the BMW K1200S. It's main aim is; never trail the pack. It was created for a thrilling riding experience, featuring a hitherto unknown combination of technology, performance and design. A slight turn of the throttle and the 123kW (167 bhp) of the new 4-cyclinder engine catapults the BMW K1200S to the front of the pack. With a torque of 130 Nm it does the 0-100 kph sprint in 2.8 seconds. The transverse installed motor offers everything a sports rider could wish for. The cylinder bank is tilted forward by 55°, the motorcycle’s center of gravity is low, and due to the engine's extremely narrow width, its leaning angle is excellent.

At the front the BMW K1200S features a world first in motorcycle production with the unique BMW Motorrad Duo-lever, as well as the newly designed and extremely light sports shaft drive, and BMW Motorrad EVO Para-lever at the rear. This sports suspension responds with extreme sensitivity and provides perfect feedback. The suspension of the 1200S is also extremely adaptable to ensure great road contact. An innovation which is unique in the motorcycling world is responsible for this: ESA (Electronic Suspension Adjustment - optional). The rider can adjust both the damping of the front and rear suspension while riding as well as the spring pre-load when stationary with the engine on. In this way the rider and machine can respond even more precisely to the road conditions.

By introducing the K1200S, BMW has enlarged its model range and entered the sporting high-performance motorcycle class, so far dominated by Japanese manufacturers.

Conceived as a sports machine from the start, the K1200S is radically new and innovative in every respect. The K1200S has no predecessor in the current BMW model range and follows no role model. On the contrary, the BMW K1200S is BMW's concept of a sports motorcycle - great riding agility, high engine power output (specifically for road performance) and safe handling in all practical situations.

The K1200S does not compromise. Instead, it combines all the features previously regarded as largely incompatible. For example: sports performance and dynamism are combined with comfort, agility and ease of handling; riding stability and high performance are coupled with everyday riding qualities; a slim-line sporting appearance is combined with efficient protection from wind and weather and great rider ergonomics.

The 1200S has all the virtues typical of BMW motorcycles. The new machine is fully suited to riding with a passenger and covering long distances; it offers a long service life and maintenance is minimal; it complies fully with environmental requirements (thanks to highly advanced emission management and a fully controlled three-way catalytic converter); and it offers active safety of the highest standard when braking (assured by the most advanced braking system on the market - BMW Motorrad Integral ABS).

The BMW K1200S is the only sports motorcycle to feature a maintenance-free shaft drive. In conjunction with the Para-lever swing arm (developed to an even higher standard and reduced in weight) the driveshaft has been optimised to a higher standard than before - its higher level of unsprung mass is virtually imperceptible even when the rider hangs on the cable.

The first decision in the approximate five-year development period (from the initial idea through to production reality) was to carefully consider the overall concept regarding the drive-train, configuration and arrangement of the engine, and the overall package. It soon became clear that the advantages of a low centre of gravity, typical of all flat-twin and existing K-models, had to be retained on the new motorcycle. Research and examination of different engine concepts confirmed that (from the perspective of power, weight and space requirements) a four-cylinder power unit fitted crosswise was the optimum solution for high-performance motorcycles. The only drawback with that configuration was a high centre of gravity. However, by tilting the cylinder-bank forward 55 degrees, and fitting the engine at it lowest possible point, BMW's engineers overcame that particular disadvantage. In addition, the entire engine block is extremely narrow to ensure adequate clearance when leaning into bends - allowing an exceptional angle of lean. Together with the extra-low, V-shaped radiator, the configuration interacts with the wheel suspension and guidance units to allow ideal frame curvature above the cylinder head to keep the motorcycle slim and narrow. With the frame profiles running close together at the rear, the new K1200 shape also enables the rider's knees to be tightly pressed against the bike.

The great seating position is tailored for the rider and allows an active riding posture with clear vision of the front wheel. It also has an appropriate standard of comfort and relaxation. The result is that the K1200S handles dynamically and safely in every situation, making confident riding on the road.

The Duo-lever marks a quantum leap in technology in front-wheel suspension and makes a significant contribution to the motorcycle's riding characteristics. By introducing this all-new, front-wheel suspension system BMW has enhanced its suspension and running-gear technology and still ensures a sensitive response at all times, with clear feedback from the front wheel. In conjunction with the four-cylinder concept, it also offers the advantage of compact dimensions.

BMW Motorrad has introduced another world-first in motorcycle production with the ESA Electronic Suspension Adjustment which has advantages not previously seen. Based on CAN-bus technology, the advanced on-board network provides a wide range of different functions and reduces the procedures required for diagnostics by intelligently combining the motorcycle's electrical and electronic systems.

The straight-four power unit of the BMW K 1200 S displaces 1157 cc. Maximum output is 123 kW (167 bhp) at 10 250 rpm; maximum torque of 130 Nm (96 lb-ft) is delivered at 8 250 rpm - with more than 70 per cent of the engine's maximum torque available from just 3 000 rpm. The engine power is easy to control at all times, which was BMW Motorrad's clear-cut objective when developing the new machine. Weighing just 81.3kg (179.3lb) including the clutch and gearbox, the engine is one of the lightest of its size in the market.

A well-conceived overall configuration, plus space-saving arrangement of auxiliary systems and the integrated gearbox enables a compact drive-train with ideal concentration of masses in the middle of the motorcycle. The crankshaft of the BMW K1200S is just 430 mm wide, placing the engine of the BMW K1200S closer to current 600cc power units than engines in the 1000cc-plus segment.

A wide range of innovative details - with design concepts carried over from the BMW's motorsport technology - added up to the creation of a unique drive system. And, as in Formula 1, it is not individual features and qualities but the perfect interaction of technical solutions and the optimum integration of the chassis and suspension. BMW's engineers overcame the inherent disadvantage of the relatively high centre of gravity of a conventional four-cylinder engine by applying a solution of typical BMW ingenuity: the engineers intelligently built on a well-known principle, enhancing its design concept to an even higher standard, by tilting the cylinder axis 55 degrees forward. This not only ensured a low centre of gravity but also provided the desired load on the front wheel - ideal for a sports riding - giving a precise feel of the surface and clear feedback from the front end. The more acute angle also provided space for an aerodynamically-efficient intake system (directly above the engine) to ensure an ideal flow of power.

The crankshaft of the 1200 power unit is forged from one piece of heat-treated steel. It comes with eight counterweights and the usual crank angle of 180° for consistent firing intervals. The stroke/bore ratio ensures adequate overlap of the bearing journals for superior stiffness. The crankshaft runs in anti-friction bearings with the main and conrod bearing journals measuring 38mm in diameter. The principle of supplying oil to the crankshaft and bearings has been adopted from Formula 1. Instead of feeding lubricant conventionally in a radial flow via the crankcase to each main bearing and from there via a ring groove to the bores on the conrod bearings, lubricant for the bearings is fed directly into the crankshaft in an axial flow. From there the lubricant flows through holes in the crankshaft and onto the conrod bearings. This keeps the bearing slimmer and more compact (even though it carries the same load on the same width otherwise occupied by the groove).  The advantage is adequate freedom of design for a very short and compact crankshaft and a minimum distance between cylinders to keep the overall engine slender and compact. Another advantage of this oil supply concept is that the oil entering the crankshaft no longer acts against centrifugal forces but is supported by those forces. This allows the oil pump to run at a much lower pressure - pump characteristics and the supply volume being optimised for minimum power loss. Finally, oil supply to the main cylinders follows the usual pattern via the main oil pipes in the crankcase, to where oil supply bores lead to the bearings. Two of the crankshaft counterweights serve as gears for the primary clutch drive and for driving the two balance shafts. The other counterweights are designed for smooth-flow dynamics - the ratio between mass and inertia radius being optimised.

The engine has lightweight box-type pistons featuring an extra-short piston skirt and three rings (two compression and one oil removal ring). Despite the high compression ratio, the piston base and valve pockets are flat in configuration thanks to the flat surface of the combustion chamber. This enhances the thermodynamically-efficient combustion process and allows weight-optimised contours on the bottom of the piston. To dissipate heat on the piston base surface subject to high thermal loads, the surfaces are cooled by oil-injection nozzles in the crankcase and therefore extend service life.

To eliminate second-order free mass forces inevitable on a straight-four power unit, the crankcase, operating via a tooth belt, drives two balance shafts positioned below the crankshaft. This ensures 100 per cent balance and force compensation - the balance shafts running in roller bearings spaced symmetrically in front of, and behind, the crankshaft to avoid additional mass momentum. The balance shafts run at twice the speed of the crankshaft. To minimise dissipation of sound waves and noise, the balance weights are connected via elastomer elements to the balance shafts.

The output, performance features, quality of combustion and fuel economy of an engine depend to a large extent on the cylinder head and valve drive. In its design and construction, the four-valve cylinder head of the 1200S is conceived to ensure optimum duct geometry, compact dimensions, optimum thermodynamics, and a reliable thermal balance. The single design feature absolutely crucial to optimum design and configuration of the cylinder head is the valve angle. A particularly tight or narrow valve angle, for example, will provide a straight intake duct and compact combustion chambers for high compression and optimum efficiency. The criteria crucial to valve drive and optimum output at smooth and unproblematic engine speeds (not affecting the valve drive) are stiffness, the minimisation of moving masses, and maximum overlap on the valves.

In choosing the configuration of the K1200S power unit, BM's engine specialists have opted in favour of follower arm timing with two overhead camshafts. This offers the perfect combination of maximum stiffness and minimum weight on the moving valve drive components, together with compact design of the cylinder head. Indeed, it is no coincidence that this principle has become the usual standard on today's Formula 1 power units. BMW's engine specialists were, therefore, able to capitalise on all their experience in motorsport in terms of lubrication and surface coating.

The valve angle on the 1200 power unit is 10 degrees on the intake and 11 degrees on the outlet side - figures so far not produced by any other contemporary engines. Out of the two overhead camshafts, only the outlet camshaft is driven by a chain from the crankshaft, the intake camshaft being driven by gear drive from the outlet shaft. The big advantage is that this requires only one sprocket on the cylinder head. The entire concept thus provides an even greater precision in valve timing and keeping the width of the cylinder head to a minimum.

The camshafts are located directly above the valves. The overall layout of the cylinder head allows an ideal 1:1 transmission ratio on the follower arms, thus keeping flexural tension to an absolute minimum and allowing the use of extremely delicate, lightweight levers. The speed limit chosen for practical purposes on production models is 11 000 rpm, while in mechanical terms the parts and components are able to take and withstand far higher speeds. Valve diameter is 32mm on the intake and 27.5mm on the outlet side.

As already mentioned, the narrow valve angle keeps the combustion chambers compact with a flat upper surface. This is the prerequisite for a high level of geometric compression with a thermodynamically designed, largely flat piston floor. The compression ratio of 13:1 is unprecedented on a standard-production petrol engine, clearly confirming the ideal geometry of the combustion chambers with an ideal combustion process and optimum efficiency.

The K1200S comes with dry sump lubrication. The advantages of this principle are supreme dependability with a steady oil flow, even under extreme conditions, and the flat design of the crankcase, keeps the entire engine in a flat and low position enabling a low centre of gravity. Not requiring an oil sump, the power unit is 60mm  lower than with conventional construction. The oil reservoir is situated in the frame triangle behind the engine. The dual oil pump, driven by a chain from the clutch shaft, is housed in the rear crankcase area, drawing lubricant from the oil reservoir and feeding it under pressure initially to the oil filter (main flow filter) on the lower left side of the crankcase (within easy access from outside). From there, the pressurised oil flows into the main oil line in the crankcase and is spread out through internal holes leading to the lubrication points. The oil flowing back gathers at the lowest point in the crankcase in a recess within the bottom cap. The second pump delivers the oil flowing back, first to the oil cooler and then back to the oil tank through a patented re-flow system. The oil cooler is in the front fairing in a favourable flow position beneath the headlight. Finally, reflecting the overall philosophy of the machine. In an ingeniously simple process, the oil level is checked through a transparent, patented plastic tube outside the oil tank - used in service to drain oil from the tank with an overall volume of 4.2 litres.

An intelligent cooling concept ensures a perfect thermal balance within the engine. The flow of coolant between the cylinder head and the cylinders is subdivided 73:27 by appropriately dimensioned flow cross-sections. The coolant flows crosswise through the cylinder head with re-cooled coolant entering the cylinder head on the "hot" outlet side.

This means that thorough cooling of the cylinder head ensures rapid dissipation of heat and an optimum temperature balance precisely where the thermal load is greatest.

The reduced flow of water on the cylinders enables the engine to warm up more quickly and reduces cold running wear and friction, also improving fuel economy.

To keep the1200 S slender and dynamic, the electrical ancillary units (as well as the drive systems) are fitted behind the crankshaft in the open space above the gearbox. The alternator is driven by the primary gear on the clutch.

Bm's K1200S is also unique among production motorcycles in its gearbox technology: for the first time in the history of BMW shaft drive, the BMW K1200S features a multiple-plate oil-bath clutch, and a gearbox fully-integrated with the angle drive in the engine housing. The big advantages of this configuration, of course, are compact dimensions and efficient concentration of mass weight. By introducing this concept, BM has not taken the usual approach. Instead, the gearbox is a separate, built-in unit commonly referred to as a cassette gearbox. This concept comes from motorsport where it allows rapid and efficient replacement of parts. On a production machine it offers advantages in the assembly process because the gearbox can be pre-assembled as a single unit. With the gears shifted by claws, the two-shaft gearbox is slender and light. The natural process of shifting from one ratio to another is conducted by a gearshift cylinder, gearshift forks, and slide wheels to provide positive engagement. To save weight the hollow gearshift cylinder is made of a high-strength aluminium alloy running in roller bearings. A particularly smooth gearshift is ensured by anti-friction bearing bushes featuring a smooth bronze/teflon surface coating for minimum friction.

To keep the gearbox short and compact, the two transmission shafts run above one another. The gears themselves are straight-toothed, which not only improves transmission efficiency, but also helps to keep the gearbox slender and avoid extra width. Thanks to the compact structure of the transmission and the minimisation of noise from the gearbox housing, running noise is reduced to a low level.

Like all large BMW motorcycles, the K1200S features a driveshaft to convey power to the rear wheel. With the engine fitted crosswise, the shaft drive configuration requires two pivot points - the pivot unit leading from the gearbox is fitted in the gearbox cover.

The loss of efficiency resulting from such double-pivotal transmission is often overestimated because, in practice, it is only a few per cent. In comparison, studies confirm that because of a certain degree of wear and contamination, chain drive suffers a significant increase in friction. This reduces the degree of efficiency. Shaft drive operates without wear and maintains a consistent standard of efficiency throughout its life.

The BMW K1200S boasts the most advanced digital engine management currently available on a motorcycle. Indeed, BMW's BMS-K (BMW Engine Management with Anti-Knock Control) Digital Motor Electronics is an in-house development specifically for motorcycles. The new generation of BMS-K technology was featured for the first time on the BMW R1200GS and has now been upgraded for four-cylinder power units. Its most significant advantages are fully sequential, cylinder-specific fuel injection, integrated anti-knock control, rapid processing of comprehensive sensor signals by means of the most advanced micro-electronics, compact layout, low weight, and self-diagnosis. By introducing this sophisticated management system, BMW Motorrad is further enhancing the unique qualities already held for so many years in electronic engine management.

The alpha-n management principle - with indirect determination of air volume intake as a function of the throttle butterfly angle and engine speed - has been exported from BMW's existing models. Engine speed and the throttle butterfly angle are as before and (by means of a potentiometer) remain the basic factors for determining the engine operation. Then, by assessing additional engine and ambient parameters (including engine temperature, air temperature, ambient air pressure) the engine management system, focusing on control maps and built-in corrective functions, tailors the volume of fuel injected and the ignition timing point to specific, real-time requirements. Fuel injection is fully sequential so that fuel is injected individually into the intake ducts, precisely geared to the intake stroke in the respective cylinder.

Variable fuel pressure control in the supply system is another first-time achievement on a production motorcycle. The system does not have a re-flow pipe or function, but delivers only the amount of fuel consumed by the engine. In practice, this highly efficient control of fuel supply allows fuel pressure to be varied almost at random for optimum fuel/air mixture formation. Fuel supply is thus tailored to actual requirements by the electrical fuel pump, applying a principle unique on a production machine. The fuel/air mixture is controlled by an oxygen sensor fitted at the junction point of the four exhaust manifolds for precise determination of exhaust emissions and their composition. The result is greater riding pleasure combined with even better environmental compatibility ensured by exemplary emission management and low fuel consumption, and enhanced by precise riding and a sensitive response.

BMS-K also comprises the automatic idle speed and cold-start control functions. Idle speed is increased automatically whenever required in the warming-up process. It is controlled by an idle speed stepper (bypass ducts for additional air) integrated into the airbox, and by specific adjustment of fuel injection volume. Measuring 46mm in diameter, the throttle butterflies come with patented operation featuring progressive adjustment. The butterfly position is predetermined by the rider turning the throttle and is controlled with greater precision by a step motor optimising engine response and fuel amount.

Incorporating various functions as one, the entire system is lighter than ever before. The three-piece injection rail, made of plastic, incorporates the fuel pressure sensor and rod-shaped high-energy ignition coils housed in the cylinder head enhance efficiency of the new engine management system.

Fuel consumption of the K1200S is 4.7 litres/100km at 90 kph (like we can ride these speeds, on a bike like this) and 5.5 litres/100 km at 120 kph.

A major contributory factor to this great efficiency is the unusually high geometric compression ratio of 13:1, a new record made possible only by anti-knock control. Following the BMW R1200GS, the BMW K1200S is the second BMW motorcycle to feature this protective function as standard. Two solid body sound sensors positioned between cylinders 1/2 and 3/4 detect any knock effects in the combustion process. The engine's electronic system responds by retarding the ignition and thus protecting the engine from possible damage. Conceived for unleaded premium-plus fuel (98 RON) under normal conditions, the engine, thanks to its efficient knock control, is able to run without the slightest problem and without manual intervention on premium (95 RON) or regular (91 RON) fuel. The only difference when using lower quality fuel is a slight decrease in maximum output and a slight increase in fuel consumption.

With the engine tilted so far to the front there is space for an airbox right above the engine. The four intake manifolds lead directly into the intake system without any curvature that would reduce efficiency. With a volume of 10 litres, the airbox helps to boost the power of the engine and contributes to its high level of torque. Two funnels extending straight to the front for optimum flow conditions, draw in the air required (from right and left of the headlight) in the ram pressure area on the fairing. Particularly at high speeds, this ram-air effect helps to further increase the cylinder charge. The intake air then passes through two separate paper filters at the end of the funnels before going into the airbox. To facilitate service and maintenance, the filters are within easy reach after removal of the fairing side sections.

Apart from the modern cyclone oil separator (serving to purge air from the engine) the airbox also comprises the idle control system. It serves to hold the battery and is another example of well-conceived, functional integration to save both space and weight.

Four individual exhaust manifolds equal in length initially merge beneath the gearbox into two pipes and from there form a single pipe leading into the extra-large rear-end silencer (4-in-2-in-1 exhaust system). Round in shape, the silencer has a volume of 9.5 litres and operates according to the reflection principle. The outer skin of the silencer is protected thermally by the inner absorption layer, the metal-based catalyst incorporating 200 cells/inch˛ is fitted at the entry point of the manifolds leading into the silencer. The catalyst coating is a combination of rhodium and palladium, particularly resistant to high temperatures and with a long service life.

The entire silencer system made of stainless steel weighs a mere 10.4kg making it the lightest exhaust system with a fully controlled catalytic converter in its market segment. One look at the way the manifold is fastened to the cylinder head shows the great attention to detail in the quest to save every gram.

The frame, again for the first time, is of light alloy with inner high-pressure profiles visible from outside. The highly stable wheels are particularly light and almost delicate in design. Together with the rider's seating position, appropriate interplay of the suspension and the position of the engine ensures not only a low centre of gravity with the desired concentration of masses, but a well-balanced, ideal wheel-load distribution of 50:50.

High-precision, robot-built lightweight frame. The central load-bearing component on the BMW K1200S is the main frame which forms a bridge structure. The frame itself is a welded, composite configuration made of internal high-pressure moulded elements (IHU profiles). This forms the curved profile sections at the side and extrusion-pressed profiles together with die-castings that form the frame head and rear end with the swinging arm mounts.

The K1200S is the first motorcycle with IHU-profiles. A high-precision robot welds the components together to form a common extra-rigid unit. With the engine tilted far to the front, the profiles on the main frame extend to the rear above the cylinder head. This means that shape is not dictated in any way by the width of the cylinder head. It also ensures ideal design and configuration of the frame which is kept appropriately slim and slender - an advantage also provided by the newly designed Para-lever swing arm, making it possible to locate the footrests lower.

Despite the low footrests, the rider of the K1200S is able to lean over to an angle of more than 50 degrees in bends thanks to the overall configuration of the suspension and engine. The low frame structure, in conjunction with the new front-wheel suspension, also serves to provide smooth inflow of forces, thus minimising the loads acting on the frame. The mainframe weighs a mere 11.5kg. The engine is firmly bolted to the frame at six points and acts as a reinforcing element without assuming any load-bearing function. The lightweight rear frame is made of rectangular aluminium profiles welded to each another and bolted onto the mainframe.

The front-wheel suspension is the most crucial component in giving a motorcycle ultimate riding precision and comfort. Recognising this essential criterion, BMW has introduced all kinds of innovations on the front-wheel suspension. The first hydraulically dampened telescopic fork on a production motorcycle (1937); the longitudinal swinging arm ('50s and '60s); the long-stroke, high-comfort telescopic fork ('70s); and the Tele-lever (1993) were (and are) milestones in motorcycle technology invented or at least enhanced by BMW and featured for the first time on BMW production machines. To this day the Tele-lever is the only front-wheel suspension system able to achieve genuine success next to the dominating telescopic fork.

For the K1200S, high-performance sports machine, the engineers at BMW set out to find an even better solution with perfect kinematics. This was quite simply because the wheel elevation curve on all wheel guidance systems inevitably involves a certain compromise between the direction of spring response (comfort and fine response), anti-dive effect when applying the brakes (residual spring travel and feedback when braking), and the motorcycle's handling and riding stability.

The engineers found the right basic idea and philosophy in the Hossack fork developed by British inventor Norman Hossack back in the 1980s: front-wheel suspension with two longitudinal arms in parallelogram arrangement. Studies conducted by BMW at the time of Hossack's invention showed that this configuration offers its advantages only in interaction with suitable wheel geometry. This meant that, for reasons of the package alone, it was not suitable for BMW's motorcycle and engine concepts at that time. But when the original concept of the K1200S started to take shape, the engineers took a closer look at Hossack's wheel guidance principle before developing and optimising its kinematics and ultimately reaching production standard.

The kinematics of the new system - now named the "Duo-lever" - fulfils several contradictory requirements all in one: a rectangular pivot made of two almost parallel longitudinal arms turning within the frame holds the wheel bearing and allows the necessary lift motion. The wheel bearing, a light casting made of high-strength aluminium alloy, is connected to the longitudinal arms by two ball bearings and is, therefore, able to convey the steering forces and motion required. The straight line connecting the two ball joints forms the steering axis, an assembly similar to a pair of scissors. This serves to convey steering movements and disconnect the entire unit from wheel lift.

A central spring strut pivoting on the lower longitudinal arm, finally, provides the suspension and damping effect required. The two longitudinal arms are suitably aligned to one another, allowing the wheel to adopt an almost ideal motion. Thanks to the kinematic configuration of the overall system, wheel elevation follows an almost straight line, with castor and wheelbase hardly changing regardless of spring travel. The wheel elevation curve is angled slightly to the rear, allowing the wheel to follow bumps and unevenness on the road in a natural process both when under pressure and in the rebound mode, thus evading undue forces and impacts from the surface.

In combination with the low-friction rotational movement of the longitudinal arms, spring response remains smooth and consistent even under high lateral forces, or when subject to severe bumps. The set-up of the suspension can be kept firm and taut without any noticeable reduction of comfort, thus maintaining the standard expected of a sports motorcycle.

With wheel forces being supported at a low point by the longitudinal arms (which keep the lever arm versus wheel contact point short and efficient), forces and momentum are fed into the frame in a smooth, favourable process reducing the load acting on the frame. The front-wheel suspension combines maximum stiffness with minimum weight because the shape and contours of the wheel mount can be chosen as required - thanks to the die-cast structure - thus being adjusted perfectly to force and momentum curves. The individual choice of wall thickness tailored to loads and forces helps reduce the weight of the entire structure without making any concessions in terms of strength and stiffness. Finally, following the main direction of force application, the longitudinal arms are subject to forces primarily in their own longitudinal direction; these are tensile and compression forces, meaning that through their configuration alone the arms are particularly stiff and sturdy.

Weighing only 13.7kg the entire construction is about 10 per cent lighter than a comparable Tele-lever. The geometric configuration of the spring strut support allows a slightly progressive effect with an overall spring travel of 115mm (60mm inbound, 55mm rebound). At 32 degrees right and left, the handlebar angle maintains the usual standards.

Through its kinematic configuration, the Duo-lever provides an anti-dive effect when braking - and the special point is that this effect remains largely consistent throughout the entire path of spring travel. Longitudinal forces acting on the front wheel when applying the brakes cause virtually no compression of the spring, only the dynamic distribution of wheel load resulting in a slight dive effect giving the rider the usual feedback on how hard the brakes are being applied - similar to conventional telescopic forks. Ultimately, therefore, the Duo-lever combines the feedback from the front wheel (so desirable to a sport rider) with the comfort and safety benefits of brake dive compensation.

Shaft drive is absolutely indispensable on a large BMW motorcycle and was, therefore, the obvious drive system for the K1200S with its power unit fitted crosswise. Indeed, this not only reflects a BMW tradition but also (and in particular) offers well-known functional advantages: the truth is that a chain requiring careful service and maintenance is simply not appropriate on a top-end sports motorcycle for superior riding pleasure over long distances. The challenge in developing the BMW K1200S was to minimise the higher unsprung masses of a driveshaft and make sure the rider does not even feel the effect.

The ideal way to do this was with BMW Motorrad's new universal driveshaft unit complete with Para-lever swing arm (presented for the first time in early 2004 on the BMW R1200GS). Much stiffer and lighter than its predecessor, and slim and dynamic in appearance, this lightweight construction is a perfect complement for the concept of the new K1200S. In design and construction it has been modified to meet the needs of the four-cylinder power unit and is appropriately strengthened for the extra power of the engine.

The K1200S is the best Beemer I've ever ridden

mmm... my kind of bike, comfortable, fast (very fast) and stylish, with all the safety features we've come to expect from a BMW.

The suspension system features high-quality, gas-pressure spring struts front and rear. Spring travel is 115mm at the front and 135mm at the rear. In its standard configuration, the rear sprung strut allows infinite adjustment of the inbound stroke for optimum damping and infinite adjustment of the spring base by 10mm enabling the rider, simply by turning a wheel, to set the suspension to different loads.

As an option, the rider is able to conveniently adjust the suspension and damping simply by pressing a button on the handlebar. Referred to as ESA or Electronic Suspension Adjustment, this system provides the option to adjust the suspension set-up with maximum comfort even when riding. Indeed, this is the first electronic suspension adjustment system on a motorcycle that adjusts the spring base as well as the damper inbound and rebound strokes on the rear wheel - and the inbound damping effect on the front wheel.

To make operation of the system as simple as possible, and to avoid the risk of incorrect adjustment, all the rider has to do is enter the motorcycle's current load condition ("solo", "solo with luggage", and "rider with passenger and luggage") and the system will adjust the spring base electrically by itself.

Depending on style of riding, the rider also has the choice of Comfort, Normal or Sports mode. Taking this input, the electronic control unit then chooses the appropriate damper rates based on optimum parameters - pre-set in the motorcycle's Central Electronic System (CES).

In all, this provides a choice of nine different variants, with the rider being able to change the damper setting while riding simply by pressing a button. For reasons of function and safety, the spring base can be reset only when the motorcycle is at a standstill. An electric motor complete with its own transmission serves to vary the spring base as required, while the damper rate is modified by small step motors on the damper.

The cast, light-alloy wheels were specially designed as brand-new highlights on the 1200S. Light, but at the same time very stable, the wheels come with special spokes designed with the help of a new, biontic calculation model taking the wide range of load requirements into account. The big advantage of such biontic calculation models is that they make allowance for structural principles and concepts of the same kind as nature: proceeding from load data and tightening parameters at the fastening points, such models calculate the optimum shape and design of a component in an iterative, step-by-step process.

The aesthetic benefit is that the front and rear wheels look light, delicate and dynamic. Despite these similar looks, the wheels are quite different in structure and layout. On the front wheel, the brake discs rest directly on a stable wheel spider without any carrier elements in between. The five radial arms of the spider extending from the hub and split, like forks, to support the rim via 10 cast spokes. With the forks being split tangentially and the spokes following a radial configuration, the front wheel offers excellent radial stability even under high wheel loads. A further advantage of this configuration is that it effectively resists the main load caused by high circumferential forces when applying the brakes.

This special design of the wheel, tailored to load conditions, helps to keep the spokes particularly slender and delicate, not only reducing the weight of the wheel but also giving the entire wheel structure a light and almost "transparent" look. On the rear wheel, the rim is also supported by 10-spoke arms in similar orientation. The difference is that in this case the spokes do not fork out, but rather extend all the way to the wheel hub. The brake disc is bolted onto the wheel flange. Dirty fingers and inconvenient hassle in checking tyre pressure are now a thing of the past because the tyre valve is integrated into one of the spokes at the side, ensuring convenient access in nearly every position of the wheel.

Wheel dimensions are 3.5in x 17 at the front, and 6in x 17 at the rear, running on tyres measuring 120/70-ZR17 and, respectively, 190/50-ZR17.

The BMW 1200 S comes with BMW Motorrad's widely-lauded EVO brake system already featured in other flat-twin and K-Series models. The brake hoses are steel-clad for extra strength and safety, brake disc diameter of 320mm at the front and 265mm at the rear ensuring maximum stopping power even at very high speeds and with heavy loads. In numerous tests this sophisticated system has proven its further benefits such as faster build-up of brake pressure than any other system. Brake operating forces are also kept to a minimum.

Ultimately, BMW's EVO brake system (EVO stands for Evolution) is one of the safest and most effective brake systems on any motorcycle. On the BMW K 1200 S this sophisticated brake system is standard, while BMW Integral ABS system is optionally available as the partly integrated sporting version; "partly integrated" means that both brakes (front and rear) are activated whenever the rider pulls the hand brake lever, while the foot brake lever acts only on the rear-wheel brake. Integral ABS has been modified to match the sporting configuration of the BMW K 1200 S, and its control functions have been enhanced to a standard even higher than before.

With the sports rider requiring a brake system that allows good feel and variable application of the brakes the BMW K1200S precisely meets that requirement - virtually eliminating the risk of the motorcycle dropping over even when braking all-out. This advantage is ensured by the low centre of gravity and the particular geometry of the suspension interacting with the kinematic configuration of the Duo-lever. As a result, the ABS control system is able to capitalise on maximum tyre grip and friction, even when the rider applies the brakes to their maximum, guaranteeing supreme safety even during the most extreme braking manoeuvres.

When introducing the BMW R1200GS early in 2004, BMW Motorrad presented its Single-Wire-System, a highly advanced, all-new system networking electrical and electronic components on the motorcycle. Combining sophisticated electronics with CAN-bus technology (Controller Area Network) this innovative on-board network offers a much wider range of functions than other conventional on-board networks, at the same time significantly reducing the number and intricacy of cables required.

With the SWS network, information is conveyed through one single wire (hence the name). And to ensure absolute security in a fully redundant system, the configuration comes with two wires for appropriate back-up.

The most significant benefits of this intelligent combination of electrics and electronics are the reduction of weight on both the wiring harness and the components used, a high level of robustness, and comprehensive diagnostic abilities. A further advantage is the easy integration of electronic accessories into the network, simple updates serving to flexibly extend and enhance the system whenever required.

The basic principle is to integrate all control units through one single wire to provide a common network transmitting all signals regardless of their subsequent function. The network comprises all information at all times, for all the components integrated into the system. The signals are then allocated to the right address at specific junction points, going straight from there to the appropriate electronic control units responsible for specific power-consuming items. There the information is processed and the appropriate functions are activated. This eliminates the elaborate and complicated process of wiring each individual function through a separate line, which also reduces the potential sources of error inevitable in a conventional on-board network due to the large number of lines and connectors. And this, obviously, is crucial to a high standard of all-round reliability.

The BMW K 1200 S comes as standard with an electronic immobiliser. Controlled via a transponder in the key to the ignition, this sophisticated system offers anti-theft security of the highest standard, equal to the security of a BMW car.

As soon as the rider inserts the key in the ignition lock and switches on the ignition, a chip in the key communicates with the Digital Motor Electronics via the ring aerial integrated in the ignition lock. Incorporating the electronic immobiliser algorithms, DME then initiates a challenge response process (the engine control unit activates a random "challenge" and the ring aerial / key replies with an appropriate "response" in order to identify themselves) and triggers an exchange of data between the coded chip and the electronic immobiliser. The data exchanged changes each time the engine is to be started. Whenever the response from the ring aerial fits the challenge presented, the engine control unit will release the ignition and fuel injection and the rider can start the engine. This technology is currently the best and most secure immobiliser technology available.

The new on-board electronic system of the BMW K1200S allows the introduction of a highly advanced, fully-digitised, extra-light instrument cluster comprising the speedometer, rev counter and an information display referred to as the Info-Flatscreen. The Info-Flatscreen provides information on coolant temperature, the level of fuel in the tank, the time, and the gear currently engaged. If the motorcycle is fitted additionally with ESA Electronic Suspension Adjustment, the Info-Flatscreen provides additional information on the current suspension set-up. The overall mileage of the motorcycle, trip mileage, and the remaining mileage available from fuel left in the tank are also available on request by the rider. Any deficiencies in the system are shown by appropriate signals on the display. The entire instrument cluster is masterminded by a photoelectric cell and automatically illuminated at dusk.

All the motorcycle's switches and manual controls are of the latest generation introduced for the first time on the BMW R 1200 GS. The particular fortes of these switches and controls are a high level of function, clear design, and easy accessibility. The basic arrangement of switches and BMW's logic in operating the direction indicators has been maintained.

In its overall design, the BMW K1200S combines power with elegance, sportiness with perfection. Clear emphasis of the motorcycle's transparency and "lightness" is provided by visible technological highlights on the frame, the wheel mounts, and the wheels themselves.

The design of the BMW K1200S is absolutely unmistakable, entering new territory without any role models. Clearly, it is a motorcycle without a predecessor in the BMW range. It is brand-new in every respect. Yet in the harmony of its lines and in its expressive style, this new machine is clearly recognisable as a BMW and a member of the K-family. Virtually every visible component on the new motorcycle is also an element and product of design, particularly the fairing, headlight, fuel tank (with its cover on top), and the rear end complete with seat are crucial to the overall design concept.

On the road the fairing of the BMW K1200S proves its aerodynamic qualities as the result of comprehensive tests in the wind tunnel. The objective in developing the fairing was to offer best-in-class protection from wind and weather, the emphasis once again on relaxed, enjoyable motorcycling and not on the achievement of merely theoretical records (such as air resistance reduced to a minimum). The flow of air on the fairing is guided by the side contours and the convex "blade" shape around the edges of the windshield to minimise wind pressure on the upper body of the rider and divert rainwater past the rider's shoulders.

Gill-shaped openings at the edge of the fairing around the sides use differences in air pressure to guide rainwater past the rider's feet. A carefully designed additional splashguard keeps contamination around the sides and at the rear to a minimum. At the front, the shape of the front-wheel mudguard supports the flow of air to the radiator, airflow to the oil cooler and the radiator itself being optimised to such an extent that the BMW K1200S, despite its power and performance, requires only relatively small cooling surfaces. Thanks to the modular structure of the fairing, partial removal of fairing elements for servicing is simple and straightforward. The front end, which is made of two plastic shells, is a self-supporting unit and offers a wide range of support and fastening functions in holding cables and fairing components. The headlight is a load-bearing element on the front end, again helping to keep the entire structure light and easy to assemble.

Striking in its design, the headlight of the 1200S houses no less than three units (one low-beam, two high-beam) with H7 bulbs. The headlight cover finished in clear-glass look is made of impact-proof extra-light polycarbonate. The reflectors in free-form surface technology are tailored precisely to geometry light requirements, ensuring an excellent light distribution and illumination of the road ahead. To facilitate replacement of the bulbs, the headlight is easily accessible from the rear.

The fuel tank on the 1200S is made of light, impact-resistant plastic and has a capacity of 19 litres  including 4 litres reserve. The tank is fitted almost in the middle of the motorcycle, behind the airbox, helping to provide a perfect centre of gravity. The overall package of the motorcycle serves to keep the tank slim and slender around the rider's knees, allowing optimum knee grip. The shape and design of the tank follows functional requirements and the space available, its compact structure providing maximum capacity with minimum material. Production of the tank in a rotation process allows maximum freedom in the external design of the tank and its structure. This freedom BMW's designers have used to give the tank fairing a clear contour with interchanging light and shadow effects for a different look from every perspective.

The seat also follows this interesting design language continuing into the panels at the rear. In designing the double seat, the designers and ergonomics specialists focused on a criterion called "step arch length" (1,810mm). This specific measurement covers the total distance between the rider's two, foot contact points on the ground measured over the inner length of the legs, taking not only the rider's height into account but also the shape and width of the rider's seat. While the seat itself is not adjustable, its distinctive waistline around the tank ensures very good access to the ground and at the same time keeps the rider's knee angle very comfortable. A further advantage is that this configuration offers the rider significant freedom of movement even with a sporting style of riding. The height of the standard seat is 820mm.

Although the seat is sporting and slender in design, the seating areas for the rider and passenger have been carefully designed to provide sufficiently wide seat surfaces with adequate support. The final result, therefore, is a standard of seating comfort superior in the sports motorcycle market, particularly for the passenger. Despite its sporting character, the BMW K1200S is just as suitable as every other BMW for riding long distances, going on an adventurous tour, or taking a passenger in genuine style. Indeed, straps for fastening luggage integrated beneath the seat make the K1200S even more suitable for a lengthy journey.

Diagram showing layout of the K1200S, with motor placed low in frame (low centre of gravity).

Great performance is ensured by a free-revving, high-output, inline-four, power unit with features carried over from Formula 1

 

 Specifications

   

 Engine:

4-stroke, in-line 4 cylinder

4 valves per cylinder

 

Cooling

Water

 

Displacement

1157 cc

 

Gearbox

6-speed

 

Power Output

123 kW at 10,250 rpm

 

Torque

130 Nm at 8,250 rpm

 

Drive

Shaft drive

 

Bore and Stroke

79 x 59 mm

 

Mixture Preparation

BMS-K

 

Clutch

Hydraulically operated multi-disc wet clutch

Performance and

Top Speed

Over 200 km/h (way over... like about 260kph)

Consumption:

Fuel Consumption:

 

 

- at 90km/h

4.7 l/100 km

 

- at 120km/h

5.5 l/100 km

Dimensions and weight:

Tank Capacity

19 liters (inc. 4 litre reserve)

 

Seat height (unladen)

820 mm

 

Weight (Dry, without fluids)

227.5 kg

 

Weight (unladen) wet

248 kg

 

Gross weight limit

450 kg

Standard Options:

2 year unlimited mileage

 

 

3 year BMW Motorrad On Call

 

 

ABS & Heated grips

 

 

Service Interval: 10 000 km

 

Retail Price: R132 000 (Incl. VAT)

Electronic Suspension Adjustment (ESA): R5 500 (Incl. VAT)

except for the mirrors, the S is actually quite slim and nimble (nice arse).

The cornering abilities of the 1200S is excellent, even at slow speeds.

Nice and comfortable, seems it was tailor-made, just for me. I could ride this thing all day.

sorry... this was the best I could manage for a clear photo (sort of), the bike was much faster

than this, I saw 260kph on the clock, without a hassle.

As you can see, the K1200S is no slouch, able to perform as good as any other superbike.

 

Thanks to Gary Whitehouse and Rob Barnes of BMW Lifestyle Midrand

for the ride on a truly great, fast, superbike... their K1200S.

 

And to the intrepid Errol Dalton for doing the wheelie so expertly.