BMW’s employees of 1923 were doubtless proud of their first motorcycle.
The R32 was a flat-twin roadster featuring shaft final drive, black paintwork and a round, blue-and-white quartered tank badge inspired by the propellers of the aircraft engines that the German firm had produced during World War I.
The 494cc R32 was stylish, well-engineered and a fine first attempt. But few people back then could have imagined that after a century of production BMW’s range would include a family of boxers, the R18 models, sharing all those features.
Or that the marque would have effectively made the flat-twin layout its own, while increasing two-wheeled sales towards 200,000 units per year.
Those 100 years have not all run smoothly for a BMW bike division that survived another World War, and financial problems that almost saw it closed down in the Seventies.
The last couple of decades have arguably been the best, as the revitalised marque has unleashed models from class-leading superbikes to pioneering electric scooters, via all-conquering adventure bikes and six-cylinder grand tourers.
Throughout its history the German firm has been among motorcycling most innovative too, introducing features including aerodynamic fairings, advanced suspension and anti-lock brakes.
That first, simple boxer had started something special – as the highlights of a century of two-wheeled production confirm.
BMW Motorbike Models To Obsess Over
1923 – R32: RIGHT FROM THE START
BMW had a head start when creating its debut model. The former aero-engine firm from Munich already had relevant experience.
At the start of the decade it had joined the growing ranks of motorcycle manufacturers by building bikes called Flink and Helios, powered by a 494cc, flat-twin engine that was also sold to rival Victoria – all of them using it with cylinders in line with the bike.
The master-stroke of Max Friz, the former aircraft engineer who designed the first bike to be marketed as a BMW, was to turn the side-valve boxer unit sideways, placing both cylinders in the cooling air.
The R32 also featured the sophistication of a recirculating oil system, unit construction (combined engine and gearbox) and shaft final drive, plus a sturdy tubular steel frame holding leaf-spring front suspension.
It all worked. The R32 made 8.5bhp, was good for 80km/h, handled well and proved reliable. It was an immediate success, selling more than 3000 units in the first three years despite a premium price.
By 1925 it had been joined by the sportier R37, with aluminium cylinder heads, overhead valves and 16bhp output. BMW’s two-wheeled trip was off to a flying start.
1935 – R12: ART DECO HIT
BMW began the Thirties with a capable pair of 750cc boxers, the side-valve R11 and sportier overhead-valve R16, which shared a new pressed-steel frame design.
The decade’s biggest hit, though, was the R12 of 1935, which updated the side-valve model with striking art deco styling and the innovation of hydraulically damped telescopic front suspension, in place of the conventional friction-damped girder forks.
The R12 also had a new gearbox with four instead of three speeds, still with hand change.
It produced 18bhp and was good for 110km/h in standard form; or a couple of horses more and about 120km/h with the optional twin carburettors.
The R12 was a fine tourer and became by far BMW’s most successful model, selling more than 36,000 units over the next six years.
Mind you, from 1937 onwards most of those sales were to Germany’s armed forces, as the country prepared for World War II.
Not that the R12 was BMW’s main military model; that honour went to its robust successor the R75, which entered production in 1941, featured a reverse gear and was commonly used with a sidecar, becoming Germany’s closest equivalent to the US Army’s four-wheeled Jeep.
1936 – R5: MIDDLEWEIGHT CHAMP
The fittest and arguably finest of BMW’s pre-War boxers was the 494cc R5, which was launched in 1936 to fight the 500cc singles from British firms including BSA and Norton.
Its overhead-valve engine made 24bhp at 5800rpm, giving a top speed of about 130km/h, and had a four-speed gearbox with change via foot rather than hand.
Equally impressive was the R5’s chassis, which followed BMW’s supercharged factory racebike by featuring a frame of oval-section steel tubes, constructed with a new process of electric-arc welding.
The frame held telescopic forks with externally adjustable damping, and contributed to the bike weighing just 165kg, 20kg less than the R12.
The R5 was fast, reliable, oil-tight and handled very well.
As a sports model its impact and sales were reduced by the War, but it remained significant as the basis for BMW’s boxers over the following two decades.
1956 – R60: FIGHTING THE FLAMES
BMW survived World War II and restarted boxer production alongside singles in 1950, but struggled in the following decade, during which fellow German manufacturers Adler, DKW and Horex ceased production.
Bike output dropped from almost 30,000 in 1954 to barely 5000 in 1959, and the car division was also in trouble. In that year the firm was almost taken over by Mercedes-Benz, before being saved by a new business plan that included selling its aircraft engine operation.
Among the models that helped BMW through this crisis was the R60, which was launched in 1956, joining the 500cc R50 and 600cc R69 of a year earlier.
All three boxers shared a chassis featuring Earles front forks and twin-shock rear suspension, instead of the telescopic forks and plunger rear ends of their predecessors.
The R60 was powered by a softly-tuned 594cc engine and was intended primarily for sidecar use; the Earles fork layout was well suited because it resisted sideways movement better than telescopics.
A sidecar from specialist Steib was available as a factory-fitted option, creating the BMW Spezial.
The R60 wasn’t fast or glamorous, but along with its successor the R60/2 it helped keep BMW going right through the Sixties.
1969 – R60/5: COLOURFUL COMEBACK
After decades of sticking to mostly black paintwork, BMW joined the modern world in mid-1969, introducing a range of R50/5, R60/5 and 750cc R75/5 boxers with updated styling – and coloured mudguards and petrol tanks at last.
The style was fresh, but the familiar attributes of flexible performance, stable handling, practicality and comfort remained.
The /5-series models’ arrival marked the start of a new era for BMW in both technology and production.
Not only were the bikes notably more modern, emphasised by their use of telescopic forks in place of the previous Earles design, but they were assembled on a new production line at Spandau in Berlin, leaving the previous Munich factory to the fast-growing car division.
BMW was making a big effort to attract more sporting riders, and to shed its touring-biased image.
In 1972 the firm went even further by introducing a smaller fuel tank with chromed side panels and battery covers.
But the “toaster tank” proved too extravagant for most riders, and was dropped the following year.
1973 – R90S: SEVENTIES PIN-UP
The boxer with which BMW celebrated its half-century was the fastest yet – and the most visually striking.
The R90S featured a neat bikini fairing, stylish smoked paintwork (grey originally, with orange following as an option a year later), twin front disc brakes and even the luxury of a clock in the dashboard.
It was powered by a 898cc engine from the R90/6, tuned slightly to give 67bhp at 7000rpm.
The R90S couldn’t match the sheer power of Kawasaki’s Z1, or the handling finesse of Italian sportsters from Ducati and Moto Guzzi.
But it accelerated smoothly to a top speed of 200km/h, handled very respectably, and was superbly comfortable, well-finished and reliable.
For pure performance the BMW was hard to beat, as Reg Pridmore confirmed in 1976 by riding a standard-looking orange boxer to victory in the inaugural US Superbike series.
In most markets the R90S cost twice as much as Honda’s CB750 – but in many riders’ opinion, BMW’s majestic bahn-stormer was simply the best production motorcycle in the world.
1976 – R100RS: SHAPED BY THE WIND
The R100RS was a motorcycling landmark: the first series production bike to be fitted with a full fairing, which BMW developed at great expense in Pininfarina’s wind tunnel in Italy.
The bike’s sporty riding position, dictated by fairly low and narrow handlebars, meant its rider’s chest and hands were efficiently shielded, allowing effortless high-speed cruising.
The RS’s 980cc aircooled, pushrod-operated engine produced 69bhp, and stayed reasonably smooth as the bike headed towards its 200km/h top speed.
It wasn’t as fast or sporty as its shape or RS designation (shared with the RS54 Rennsport racer) suggested but there was much to admire about a model that combined high-speed stability with levels of handling and ride quality that few rival superbikes could even approach.
The R100RS was an advanced machine with a price tag to match, and reinforced BMW’s upmarket image.
Its more touring-oriented sibling the R100RT, which followed two years later with a bigger fairing and more upright riding position, gave another classy option for long-distance riders.
1980 – R80G/S: ALL-TERRAIN SAVIOUR
The R80G/S is hugely significant for two reasons: it introduced the concept of large-capacity dual-purpose bikes, and it kept BMW’s bike division in business. In the late Seventies, serious questions were being asked in Munich.
With sales plummeting in the vital US market, and a belief at BMW that the boxer motor was nearing the end of its life, the company’s boss considered closing the bike division.
That this did not happen was largely due to the unexpected success of the innovative G/S.
Based on an enduro boxer that had been successful in German and European competition, the Gelländer/Strasse (Off-road/Street) combined a 798cc motor with a chassis based on the R65 roadster.
The G/S produced only 37bhp but it was light, looked good, had generous suspension travel and, with a top speed of 160km/h, was faster than dual-purpose singles such as Yamaha’s XT500.
BMW had aimed to sell 3000 G/Ss in 1981, and sold over 6500. Encouraged by Hubert Auriol’s two wins in the Paris-Dakar Rally, the firm produced a Paris-Dakar replica derivative in 1984, with bigger tank and other features.
By 1988 the R100GS had a capacity of 980cc, BMW’s bike division was thriving and all thoughts of killing off the boxers had been dismissed.
1989 – K1: STREAMLINED BRICK
With its brightly coloured, all-enveloping bodywork, the K1 was a startling bike by any manufacturer’s standards – let alone those of traditionally conservative BMW.
In conjunction with the huge front mudguard, the K1’s fairing and large rear section combined to give a wind-cheating shape unmatched even by Japanese sports bikes.
Behind the plastic was a tuned, 16-valve version of the watercooled, 987cc four-cylinder engine that had been introduced five years earlier in the naked K100, nicknamed the “flying brick”. In K-series style the cylinders were aligned horizontally.
The fuel-injected four produced 100bhp, sufficient to send the aerodynamically efficient K1 to a top speed of over 220km/h.
A strong steel frame, based on that of the K100, firm suspension (with Paralever system to combat the effect of the drive-shaft) and a powerful triple-disc braking set-up gave good handling and stopping power.
At 234kg with fuel the K1 was too big and heavy to be a true sports bike, but it helped boost BMW’s image.
1993 – R1100RS: NEW-GENERATION BOXER
Having opted to continue producing flat-twins, BMW spent the Eighties updating existing models to sell alongside its fresh range of K-series fours and triples.
Meanwhile boxer development continued and eventually, in 1993, resulted in a new-generation model, the R1100RS – powered by a 1085cc fuel-injected, air/oilcooled, four-valves-per-cylinder, “high-cam” motor producing 90bhp.
The RS’s chassis was equally noteworthy, because it introduced Telelever front suspension. Instead of conventional telescopic forks, the system consisted of hollow fork legs, a horizontal arm pivoting on the engine, and a single suspension unit.
It worked well, giving good handling and a comfortable ride.
And the rest of the R1100RS was equally impressive.
With plenty of midrange power and a 220km/h top speed, a protective fairing, generous fuel range and powerful, anti-lock brakes, it was a sports-tourer in the best BMW boxer tradition.
1997 – K1200RS: BREAKING THE CHAINS
The K1200RS was an important step for BMW. With its swoopy styling, aluminium frame, Telelever front suspension and 1092cc, four-cylinder powerplant, the RS was every bit a modern superbike.
And with a claimed 130bhp on tap, it blew wide open the self-imposed 100bhp limit that had held the firm back for years.
That output made the bike by far BMW’s most powerful ever, and the engineers had managed to combine its new-found high-revving ability with the K-series motors’ traditionally strong midrange torque.
Its chassis also impressed.
Weighing 260kg, and with a long wheelbase, the RS was big and heavy but well-suited to maintaining a fast pace on main roads.
Along with its size, weight and high price, the RS suffered with a mediocre range when ridden hard, thanks to a combination of small tank and poor fuel economy.
But it was a rapid and refined long-distance machine that signified an important shift of attitude at BMW.
2000 – C1: CABIN FEVER
BMW claimed the fully-enclosed C1 was the world’s safest bike, with its car-style aluminium safety cell, twin seat-belts restraining the rider, and an energy-absorbing beak to reduce head-on impacts.
It was certainly the weirdest, looking like a giant egg or something from a distant planet.
Conceived with the aim of attracting motorists to two wheels, it was built by Bertone in Italy and powered by a 125cc Rotax single-cylinder engine producing 15bhp.
That gave modest acceleration to a top speed of about 110km/ph, its rider sitting comfortably – with no need to wear a helmet, in most countries – and with only a slight draught reaching the cabin.
Inevitably the tall, 185kg C1 was top-heavy and unwieldy, and expensive by scooter standards.
It made an impact on all who saw one riding past, but less so on the market.
BMW added a slightly more powerful 176cc version in 2001, but sales declined after a promising start, and production ended the following year.
2004 – R1200GS: ADVENTURE PHENOMENON
The first R1200GS was arguably the most influential and successful motorcycle of recent times.
Aided by its R1150GS predecessor, as famously ridden The Long Way Round by Messrs McGregor and Boorman, it sparked the adventure-bike phenomenon.
And since its launch it has been among the world’s best-selling models, along with its GS Adventure sibling and their R1250 successors.
The GS’s beaky style is – was – distinctive, and its 1170cc, aircooled pushrod boxer engine produced 100bhp, giving pace, refinement and shaft-drive convenience.
The chassis was equally important, notably the dry weight figure of 199kg that was 30kg down on the R1150GS.
That helped make the GS sufficiently quick and agile to be fun, both on- and off-road, to riders seeking an alternative to sports bikes.
BMW’s continual evolution, notably with the liquid-cooled R1200GS in 2013 and the R1250GS six years later, has kept both the standard and Adventure models competitive.
Rumours suggest an R1300GS is imminent, but BMW won’t be abandoning the all-conquering boxer’s finely honed format any time soon.
2010 – S1000RR: SPORTING SUPERSTAR
Of all the projects that BMW had taken on, developing an open-class super-sports bike from scratch was perhaps the most ambitious.
Japanese firms had been pushing the class limits for decades.
Yet on the S1000RR’s arrival it was not merely a contender, it was by most criteria the best of the ferocious bunch.
BMW’s engineers stuck to the established Japanese format of 999cc, 16-valve four-cylinder engine in a twin-spar aluminium framed chassis.
They found a class-leading 193bhp output with strong midrange and reliability; and crafted a chassis that combined agile handling and stability with a dry weight figure of 183kg.
The S1000RR appeared with perfect timing, boasting multiple riding modes and advanced traction control, just as rival firms, hit by the credit crunch, paused their development.
It has arguably led the way ever since with the aid of regular updates – and with exotic variants including the 2012-model HP4, which introduced semi-active suspension; the HP4 Race of 2017, with its carbon-fibre frame; and the recent M1000RR homologation special.
2011 – K1600GT: THE POWER OF SIX
The first decade of the new millennium saw BMW grow its range with models from the C1 enclosed scooter to the racy S1000RR.
For 2011 the emphasis was back on familiar touring ground, with a difference: the K1600GT and GTL were powered by a 1649cc, dohc straight-six engine.
The two models shared their 24-valve, 160bhp engine, aluminium twin-spar frame and much of their bodywork, but had subtly differing characters.
The GT, with sportier ergonomics and suspension, was aimed mainly at rapid solo riding; the GTL was more laid-back and luxurious, intended for long trips with a pillion.
Both bikes offered fierce acceleration and effortless high-speed cruising, thanks to a powerplant that matched its high-revving smoothness by generating 70 per cent of its torque peak at just 1500rpm.
Handling and comfort were impressive, and the bikes’ high prices were generally matched by their specification. This was touring with a twist – and with a uniquely addictive six-pot character.
2014 – C EVOLUTION: ELECTRIC START
As the first electric model from a major motorcycle manufacturer, the C evolution was a significant machine, if not a successful one.
It was visually similar to the C600 and C650 parallel twins with which BMW had recently entered the scooter market.
But its white and electric-green bodywork hid a large aluminium box containing three of the eight lithium ion battery cells that powered the firm’s i3 car.
That box also formed the frame, and held a front fork assembly plus a diagonally mounted rear suspension unit.
The liquid-cooled motor, located ahead of the rear wheel, produced 48bhp – enough for a top speed of 120km/h.
Due to a licensing quirk it was rated at just 15bhp, so could be ridden on an A1 licence.
The C evo was fun to ride, with lively twist-and-go performance and sound handling despite its 265kg weight.
But its bulky batteries limited storage space, and it suffered the normal issues of high price and limited range.
The electric scooter market remains tough to crack, though the recent CE 04 shows BMW haven’t given up yet.
2014 – R nineT: SPECIAL BREW
The R nineT was unveiled in 2013 to celebrate BMW’s 90th anniversary, and was right on trend.
Blending classical styling cues with high levels of finish and detailing plus built-in potential for customisation, it was the factory’s response to the popularity of old aircooled boxers with the growing ranks of specials builders.
BMW had the ideal engine in the 1170cc aircooled unit recently abandoned by the now liquid-cooled R1200GS.
A new Akrapovic exhaust system left the 110bhp output unchanged.
The rest of the bike was new and generally of high quality, notably the handsome brushed-aluminium fuel tank.
Chassis parts included forks borrowed from the S1000RR, wire-spoked wheels and Brembo Monobloc front brake calipers.
The R nineT looked stunning, was designed to allow easy personalisation, and most importantly was brilliant to ride: quick, sweet-handling, well-braked and bursting with flat-twin character.
Its success soon led to a family that included faired Racer, dirt-themed Scrambler and Eighties-inspired Urban G/S models.
2014 – R1200RT: UPDATING A TRADITION
The initials RT had designated a touring boxer ever since the R100RT of 1978.
Almost half a century later, the R1200RT arrived with a similar format of flat-twin engine, big fairing and laid-back riding position.
But with 125bhp performance, electronic sophistication and chassis ability that made it as notable for speed and excitement as for traditional RT attributes such as comfort and practicality.
Its 1170cc, dohc eight-valve engine was the revamped “vertical flow” unit introduced a year earlier with the R1200GS, modified for RT use with a heavier crankshaft and slightly taller gearing.
The tubular steel frame held Telelever/Paralever suspension systems incorporating semi-active damping control.
The fairing, electronically adjustable screen and broad seat helped ensure that those old assets of comfort and weather protection were still very much present.
But this was a much faster and sharper boxer, with lively acceleration and sweet handling that belied a fuelled-up weight of 274kg.
The RT had gained performance, agility and fun factor to such a degree that it was not just a tourer but an excellent all-rounder.
2014 – S1000R: STREET-FIGHTING SPIRIT
BMW super-naked four didn’t follow its rivals with an aggressive name like Brutale, Monster or Streetfighter.
But the S1000R shared the asymmetrical twin-headlight glare of the S1000RR from which it was developed, and the German bike was every bit as exhilarating as its look and heritage suggested.
This high-barred superbike was more than simply a stripped-down version of the RR that had set the super-sports world alight four years earlier.
Its detuned 999cc, 16-valve engine made 160bhp with storming midrange; its twin-spar chassis helped keep fuelled-up weight to 207kg; and its list of high-tech features included the first semi-active suspension fitted to an unfaired roadster.
The modestly titled four was quick, agile, refined and an instant super-naked class contender, especially as its final weapon was a price that was as competitive as its performance.
A year later it was joined by the closely related S1000XR, a road-biased adventure model whose roomy riding position and long-travel suspension gave BMW a strong presence in another increasingly vibrant category.
2020 – R18: IMMIGRANT SONG
The R18 wasn’t BMW’s first attempt at giving US riders an alternative to their V-twins; back in 1997 the R1200C had brought imaginative boxer style to the cruiser sector, without making the hoped-for dent in Harley-Davidson’s market share.
More than 20 years later, the R18 took a more traditional approach to the same task.
This time there were clearer links to BMW’s first half-century in the R18’s black-with-white-pinstripes paintwork, and in its classically simple design, which echoed the ground-breaking R5 of 1936.
The firm’s biggest ever boxer motor displaced 1802cc, and punched 90bhp and 158N.m of torque to the fat rear tyre via an exposed drive shaft.
Performance was suitably strong.
The engine’s monstrous midrange offered arm-yanking acceleration and effortless cruising; the chassis gave a well-controlled ride despite the bike’s length and hefty 345kg of weight.
Before long, screened Classic, handlebar-faired bagger and fully-dressed Transcontinental variants had joined the family to offer American touring with an unmistakably German accent.
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