Living with a BMW for any length of time is like being exposed to old guard aristocracy. One is continually aware of the need to tidy up shortcomings, to make a favourable impression on the Prussian nobleman with whom one is associating.

The bike is as accurate a mirror of national characteristics as you could imagine a piece of machinery being.

The game is played to the bike’s rules, but they’re not rammed down your throat. Its code is one of rigid adherence to a logical approach of scrupulous politeness. If you don’t measure up to its standards, it won’t brawl about it. No BMW will dump the unwary or sloppy rider on his tail as punishment. Rather, he will be treated fairly, but with a cool politeness which hides the potential of true friendship.

Break through the barrier of convention, learn the proper way to click your heels, when to bow and you’ll be opening the way to a relationship as deep and satisfying as you can have with a bike.

Above all, don’t fall into the trap of thinking the BMW is only good for touring. It received that tag only because few can equal it in the application. Earlier examples of the marque lacked the potential to become top sportsters, but in their own logical, quiet and thorough fashion, the Bayerische Motoren Werke have uprated the big twins to where they can truly lay claim to the “Superbike” title.

All that’s really needed for the word to spread far and wide is for traditional BM owners to start riding harder and the rest of the world to give the bikes a long and searching look.

A rider cast in an unashamed sporting role is John Holt, the owner of our test machine, a top of the line R75/5, complete with the ’73½ modification of longer wheelbase.

His attitudes to bikes are blunt to the point of dogmatism. Two ­strokes are dismissed en-masse with the contemptuous phrase “ring-dings” and various less printable adjectives.

Top on his list of what a bike should have is good, responsive handling. For that reason his earlier machines were British, but he found himself continually frustrated by problems of mechanical unreliability – top on his list of undesirables.

So buying the BMW was to some extent a logical step, although he confessed to trepidation in the early stages. “It took me a while to wake up to how well the bike responded to being ridden hard,” he says.

“The cost of the thing and the delusion that BMWs were built to be ridden quietly had me pussy­footing around for a long time and I was fairly disappointed. Then I thought to blazes with it and things started to click.”

John represents the type of rider the company had in mind with the introduction of the /5 range. The bike is used for daily commuting, the odd trip and just plain fun riding. He has no plans to ride cross-country to England or around Australia, popularly supposed to be the dream of every BMW owner.

Yet somehow he’s already enmeshed in the BMW mystique, and expressed concern that the newly announced R90S had lost the traditional styling concept. “Traditional” to him is the R75/5, a bike which, only four years ago itself caused weeping and wailing and cries of “spoiling the image” and “senseless modern fashion” from long-time fanatics.

But BMWs change … and never change. Perhaps the motor is what does it. An upright layout of cylinders allows almost infinite variations in looks but there’s no way to disguise two big jugs sticking either side of a huge cast alloy housing. It dominates the rest of the bike.

Live with it for a while and it dominates your thinking to the extent that every other motor style looks like a gross mutation spawned by some catastrophic freak-out in the chain of mechanical evolution.

There’s no denying the horizontally opposed twin is a sensible form for a motor to take. As each piston moves its motion is duplicated in reverse by the other; the major proportion of the out of balance moments inherent to converting linear motion to rotational motion are immediately cancelled. The result is a unit which can be bolted directly into the frame yet still be as smooth as anything around. The barrels, perched out in the airstream, need not have extensive finning and weight is concentrated low, so another bugbear of the average motorcycle disappears at once. Then, since you have a crankshaft facing fore and aft, you keep things that way with a shaft final drive.

In practice nothing could be simpler. BMW have retained the basic concept to the point where the huge tunnel casting hides many of the functions normally on display in a conventional motor. At the heart of it all the one-piece crankshaft is supported by. two big plain bearings, while the camshaft, driven by a duplex chain lies directly underneath.

As in a car, ancillaries are concentrated at the front of the shafts, the single contact breaker unit on the camshaft and the alternator on the crankshaft. In the area above the crankshaft some space is given over to the starter motor, while the balance hides the air cleaner. which breathes through an inlet on top of the tunnel under the petrol tank.

The tunnel may look huge, but it’s quite light, comprised entirely of alloy and strengthened by selective use of webs to reinforce bearing location points. With all internal bearings of the plain type, the need is for a high pressure oil supply and this is delivered by a trochoid pump geared to the rear of the camshaft. Also hidden inside the tunnel, accessible like the contact breaker and alternator through the removable front panel, are minor electrical units. The pushrods are carried in individual steel tubes exterior to and underneath the barrels.

With the barrels exposed, maintenance of spark plugs, tappets and carburettors is a straightforward affair. In fact, despite. much being hidden from view the makers have been at pains to place everything accessibly. Where this conflicts with styling, styling has invariably lost. For that reason the bike can hardly be called extra good looking; but the overall effect is of ordered simplicity.

It’s an effect that grows on you, particularly after an easy session fiddling with mechanicals or cleaning the machine down. At such times the concept comes into its own, and you wouldn’t trade it off for zoomy styling in a fit.

The one feature which most catches the eye is the superb quality of the alloy castings used throughout, and in most cases left as they came out of the mould. You have to look hard to find any areas where these have been machined to improve looks, simply because there’s no need. Their only drawback lies in their porous surfaces retaining the stains of road grime and the bodies of mashed insects, calling for a hefty detergent when washing down.

Hand in hand with the castings goes a meticulous attention to detail everywhere one looks. BMWs are built largely by unskilled Turkish and Yugoslav labour, superintended by almost equal numbers of skilled German technicians. The concept, a by-product of Germany’s permanent labour shortage, obviously works well.

The test bike was finished in bronze, one of the range of new colours the bikes have been appearing in over the past year or two. Good though it was, it couldn’t compete against the deep lustre of the traditional black on the headlight and surrounds. So remarkable is this colour it deserves inclusion in charts as a separate shade. There is no black like BMW black.

Something which escapes even a fairly searching look is the construction of both mudguards in fibreglass. You have to give them a tap to convince the eyes they’re wrong. John rose to the bait in true BMW owner fashion when we accused the bike of having “plastic” guards.

The lengthening of the wheelbase on the bike is evident when compared to the earlier model, which looked chunky and balanced. The current version has more of a rangy look; triangular chrome side panels are an option and John’s bike was not fitted with them, leading to a significant gap between the rear of the motor and the front of the mudguard.

Transmitting the oomph through to the rear wheel is catered for by a single plate dry diaphragm spring clutch, a four-speed constant mesh gearbox and a high-tensile drive shaft. This latter is contained within the right hand swing arm tube and runs in its own oil bath. A set of rubber bellows connected to the forward end of the tube in front of the swing arm pivot axis allows movement between it and the transmission.

At the shaft’s other end it is connected to the extension carrying the hypoid drive gear by an ingenious splined coupling which caters for minute length changes as the swing arm moves through its arc. With the gear carrier supported on ball bearings, everything in the final drive section operates cleanly, noiselessly and smoothly. BMW’s current advertising suggests we should get a bike with a shaft drive. Compared with a chain it does have advantages.

Further forward there are minor drawbacks. Turning at engine speed and having to quieten down the effect of big flywheels, the clutch must be strong and so must the gearshift. That both work precisely and smoothly is a tribute to their design, but it takes a gentle and expert touch to match revs properly for a silent gearchange.

In addition, there’s a distinctive rattle from the clutch or the spur cut step gear on the input shaft when the machine is in neutral with the clutch engaged. Despite grim forebodings of mechanical disaster, BMW gearbox blowups are as common as snowstorms in the Simpson Desert. Toughness is built in, the noises come for free.

Understandably, most riders prefer the electric starter when getting their mounts fired up. The motor’s location forces an unusual position on the foot operated kickstart – it swings in an arc outward from the left hand rear of the motor. Some we’ve tried have defied all attempts at easy operation; the one on John’s machine seemed better than the average, engaging far enough down so that you didn’t have to be a ballet star to reach it, yet still allowing a reasonable swing,

The motor proved easy to start under either system although warm­up time was quite long. The first impression one has when a BMW fires up is of the clockwise torque reaction; blip the throttle and the whole machine rocks gently to one side. A generous twist for a downshift at low speed also produces the same feeling. At first it’s disconcerting, after a day or so all but ignored.

Below 3500 rpm the motor didn’t seem full of fight and tended to shudder gently to itself, yet even under these conditions its smoothness and quietness were evident. The 32 mm Bing constant velocity carbs emit a subdued hollow boom which is typical of such units and the tappets tick quietly away.

The ends of the exhausts would be the least noisy part of the whole system. So efficient are these units that one suspects BMW of first designing the mufflers and matching other aspects of the motor’s performance to them. They represent design of an extraordinary cleverness or so much restriction that without them the motor would produce 50 percent more power.

One day, we’ll tear the mufflers off a BM to see what happens. Whatever the reason, the big twin is one of the few bikes in the world far enough ahead of impending noise legislation to be smug about it.

In the midrange the machine really starts to haul, from 4000 to the 6800 redline packing out more than 38.5 lb-ft (52 Nm) of torque.

Significantly, only the gutsiest of the 750 and above superbikes have as much punch over a broader band. Above 4000 the earlier tremors disappear, with finer vibration starting up at 5500 and lasting to the end.

The German twins have always been renowned as smooth, but to some extent this is more a measure of the capable way all tasks are done, plus a general through-the­range smoothness. Many other motors are smoother at their best than the BMW, but they all show signs of distress somewhere along the way. Apparently the BMW will run to the mid-7s and valve bounce and still not start yelling. That’s one story we weren’t prepared to put to the practical test.

For a fast standing quarter time it helps to run it to 7000 though. Although the four gearbox ratios are well chosen they still have large gaps between them, leading to a 2500 rpm drop on the one-two upshift. Despite the motor’s grunt the gaps and the heavy flywheels keep times up in the mid-14s.

Same for the top speed: at 174 km/h (108mph) it can be topped by most other 750s, but the BMW, being slightly undergeared, gets there so easily. The peak power — 50 very real horses (37 kW) at the rear wheel — occurs at 6300, which is a shade over 161 km/h (100 mph) in top. All-day cruising just below that point is no strain at all.

This is where the big twin shines. There’s no impression of any distress internally, the sound from the pipes is still a subdued purr, the stubby bars and gently curved seat have the rider perfectly positioned for the wind force to be taking all strain off his body and the big tank contains enough petrol for close on 400 km (250 miles). Double that distance in a single day’s riding is well within the bike’s capabilities.

At these speeds the BM has to be treated in bends the way it wants to; success only comes with practice and a particular approach. We were keen to evaluate the bike’s longer wheelbase against the previous model. Ostensibly the change was only to move the rider’s shins further away from the vacuum chambers on top of the carbs. That change was needed, but so too was a steadying down of the steering. which tended to react too much to throttle changes.

The effect is still there and still needs the proper technique to achieve the best in handling, but it has been reduced by the longer wheelbase. All that needs to be remembered with the BMW now is to drive it right through every corner. Under such conditions the bike handles in an exemplary manner.

Sloppy tactics with the throttle are rewarded with indifference from the bike. It doesn’t wobble or pitch or act in any way dangerously – it merely refuses to track in a steady line. In the tighter bends the jutting cylinders inhibit ground clearance, but since the proper cornering technique involves the body weight inboard, riders seldom have anything hang up.

This practice helps steady the quickness of reaction caused by the machine’s low centre of gravity without slowing down the speed with which it can be laid from one side to the other through a series of S-bends. Riding a BMW hard is an exhilarating experience. The road unwinds underneath in a series of long controlled swoops. Tucked hard into the bends the bike tracks with a steadiness, which as well as inspiring confidence, disguises the rate of progress.

At slower speeds, in city traffic, things are not quite so happy. The steering rake is biased towards easy effort, in other words it’s on the steep side, and despite a long trail helping the bike to track steadily low speed turns are accompanied with the tendency for the bike to steer through the manoeuvre. Throttle sensitivity is marked during tight turns, and the bike’s bulk (but not weight – it’s surprisingly light) becomes awkward.

The front suspension also leads to disconcerting habits at low speed. So good is the rebound damping and so soft are the springs that applying throttle during a walking speed turn has the forks rising by half their 216 mm (8½ inch) travel to the accompaniment of a gentle sigh from the damping.

At 127 mm (5 in.), rear suspension movement is equally generous. Here again, damping is top class and springing is soft. The result is that at medium speeds the bike tends to treat small bumps with contempt, hitting them with a slight jolt but otherwise ignoring them. Show it anything larger, anything likely to upset stability and the suspension soaks it up perfectly, keeping the bike on a comforting, steady line.

The real killer potholes will force full travel out of the front forks, still without any oscillations or loss of stability. We kept the three-way rear units up on the top preload to gain as much ground clearance as possible. Since their behaviour is little different at the softer settings, most owners keep them on top.

The clearance on John’s machine is a little less than stock because of the optional crash bars protecting the barrels. Under desperate cornering both would scrape, along with the underside of the rear brake lever on the right.

Much has been written and spoken about the clunky gearbox of the BMWs. Despite some flywheel lightening over the past three years the characteristic remains with the R75/5. Given experience and a gentle approach, nearly all shifts can be executed silently. If you want to move around anything like briskly though, forget them.

It’s a shame to pussyfoot around on such a sporting machine, so we concentrated during the test n getting the noise down from a terrifying clonk to a loud click while still enjoying the riding.

Still using drum brakes on both ends, the R 75/5 is somewhat out of fashion in its capacity range, but sports very good stoppers. The front, a double leading shoe with the levers being pivoted towards one another in the same manner as some BSA units, has a reputation for being on the savage side at slow speeds. On the test bike this was not so, probably because the operating cams weren’t in spot-on adjustment, and we found it ideal for low-speed work. On the other end of the scale, it called for too high a lever pressure in panic stops. The figures we achieved would be short of the bike’s true braking potential.

At the rear, the single leading shoe worked strongly, although long leverage and Metzeler tyres’ propensity for such antics caused locking the wheel if applied too heavily.

Despite weight transfer under brakes being high and suspension movement in the huge range, it didn’t produce the out of control sensation one would expect. The bike is very stable at all times.

The seat is on the firm side initially, but feels better the longer you sit on it. BMW either have on their staff experts in human ergonomics, are really keen about their comfort, or both.

John’s bike has a departure from stock: two Hella halogen spotlights, one either side of the main headlight. With its diffused offset pattern lens, the normal headlight operates well, but it pales to the status of a candle beside the power of the spots. We received no real chance to try them out during the test; the few times we switched them on were in or close to built-up areas. Their brilliance forced a prompt switching off.

We have been spoilt by control standardisation on the Japanese bikes over the past three years. If a machine doesn’t have layouts comparable to the current Kawasakis and Yamahas, we must give it a minus mark.

Into that range falls the BMW. The Hella switches operate positively, but lack the rock-bottom logic of the Oriental machines and need too large a stretch of the thumb to reach. The ignition “key” is a joke if you’re concerned with security against joy-riders and its method of switching on the lights is vague enough to need a fair time for familiarity.

Then there’s the speedo/tach, a unit which will be replaced in the /6 range and over which few tears will be shed. The Motometer speedo is steady, legible and fairly accurate, but lacks a resettable trip meter, while the apologetic tach segment, as well as being hidden behind control cables, has a needle which bounces over a 1500 rpm range at every upchange.

Clutch, brake and choke controls are all beautiful and do their bit in promoting the excellence of Magura equipment. Cables are well protected against the ingress of dirt and dust, the throttle will stay where left yet is at the same time feather light to the touch, and the adjusters are all easy to use and positive.

A problem peculiar to the R75/5 is blueing of the exhaust pipes. At its root probably lies the economical way the CV Bings meter out the fuel, but we noticed factory photos of the up-coming R90S reveal the same thing despite the use of more conventional Dell ‘Ortos. Perhaps it’s inbuilt.

Whatever the reason, John, whose second set in nine months has the chrome on the coupler tube starting to flake, is considering painting the headers matt black, which could solve the problem as well as look pretty mean. The exhaust hassle is the only area where any doubts can be cast on the quality of finish of the BMW.

Two other idiosyncrasies (pointed out by John) are inbuilt in every BMW. One is the way the cylinders heat up the rider’s lower legs on summer clays, the other is the way stones tend to fling over the cylinders up toward the rider on a dirt road.

Both, it seems, have to be lived with. Both are part of a very small price which has to be paid for the enjoyment of a wonderful motorcycle.

Don’t compromise on any of your attitudes to riding, simply learn to adjust your style to that of the bike. It may be an expensive and slightly unconventional one, but the world of the BMW is motorcycling at its most satisfying.

By Brian Cowan. Two Wheels, March 1974.

Ian Falloon: The Classic View

Times were tough for European motorcycle manufacturers during the 1960s. The Japanese already dominated the smaller capacity market and their success in Grand Prix racing enabled them to expand their horizons. Although they concentrated on producing motorcycles over 250cc the survival of British and European manufacturers was threatened. Built with up-to-date machinery, these new mass-produced Japanese motorcycles offered class-leading performance, and were cheap and reliable.

Although motorcycle sales sustained BMW early in the 1960s, by 1963 BMW’s new range of cars was more successful and profitable. Fortunately, in face of serious opposition, technical director Helmut Werner Bönsch managed to persuade BMW’s directors to sanction a pilot scheme to develop a replacement for the /2. With an internal designation of Type 246 this became the /5, a series of air-cooled boxer twins that would sustain BMW until 1996.

The new engine differed significantly in detail and execution to the previous /2 and was very automotive inspired. Instead of a pressed together roller bearing crank with the camshaft above, the crankshaft was a one-piece forged crankshaft type running in plain main bearings. The con-rods and bearings were straight out of the 1600cc BMW car. The single camshaft was now located below the crankshaft, and the pushrods below the cylinders, tidying the look of the engine. The /5 was produced in three capacities; 500cc, 600cc, and 750cc, and each was ostensibly identical but for the capacity.

Compared to most other motorcycles of the day the R75/5 was a user friendly machine. A 180 Watt auto style alternator powered the electrical system, a strong starter motor sat on top of the crankcase, and a fully enclosed shaft drive simply made life easy for those interested in high mileages. Long before noise and emission regulations were enforced the /5 incorporated an integrated air filter and engine breather system. Also new for the R75/5 was a set of 32mm Bing constant vacuum carburettors. Producing a modest 50 horsepower at 6,200 rpm the four-speed R75/5 was still a respectable performer, capable of around 175 km/h.

With a “Featherbed” style frame, short swingarm, and telescopic front fork, the /5 chassis also represented a considerable departure from previous BMWs. Designer Von der Marwitz believed too much frame stiffness was detrimental for a street motorcycle, bolting the subframe onto the main frame section. The long travel suspension gave a supremely plush ride for the day but the /5 never earned a reputation for sharp handling. Another area of criticism was the brakes. Although other Superbikes were moving to disc brakes, discs were untried on BMW motorcycles so the /5 had traditional drum brakes.

Even the Germans are prone to irrational behaviour and after two years BMW decided the R75/5 was too staid for the US market. Although they left the engine and chassis as before the fuel tank was downsized to 17 litres, chrome side panels added, and matching chrome plated side battery covers installed. The 1972 R75/5 soon earned the nickname “Toaster” tank because of its similarity in appearance to the kitchen appliance. But not all markets greeted the “Toaster” fuel tank with unequivocal acclaim. After sales stalled here in Australia the /5 was sold with the earlier-style larger tank as standard, and BMW Great Britain followed suit later in the year. Market resistance to the gaudy “Toaster” tank outside the US led to BMW returning to their more traditional conservative styling during 1973 but the chrome “Toaster” tank was still fitted to many US models.

With nearly 69,000 produced over four years, the /5 series re-established the BMW motorcycle tradition. Offering unparalleled touring comfort and reliability these are still viable useable motorcycles. Many spare parts are available, now remanufactured by BMW Mobile Tradition, and the /5 is one of the bargains of the classic bike world.

Five Boxing Bavarian Things About the BMW /5

• The chassis design for the /5 was supervised by of Claus von Rücker. Von Rücker came from Porsche in 1964 and brought with him Hans-Günther von der Marwitz to head the Test Department.

• Hailing from a distinguished family, von der Marwitz lived from 1927-2002 and was an avid motorcyclist. Used to racing around on an AJS 7R he was dismayed at the handling of the Earles-fork R69S and wanted the new BMW to handle as well as a Manx Norton. Thus the /5 frame was a full cradle duplex type inspired by the Rex McCandless Manx Norton “Featherbed.”

•  The BMW R75/5 was surprisingly suited to the Castrol Six-hour race for production motorcycles. While several R75/5s were entered in the early years they didn’t figure prominently on the tight 1.9 km circuit that favoured smaller and lighter motorcycles. But in 1973 Tony Hatton surprised the field, riding the six hours singlehandedly with only two fuel stops to finish third.

•  Hans-Otto Butenuth and Helmut Dähne raced the R75/5 with considerable success in Europe. During 1973 Dähne was almost unbeatable in German five production races and continued to race the short wheelbase R75/5 for many years. This culminated in victory in the 1976 Production TT at the Isle of Man on a 900cc version.

•  Soon after it was released the R75/5 was winning production races in the US and was soon developed into a 750cc Grand Prix racer by Udo Gietl. By 1974 it featured a Rob North frame and for two years the BMW F750 racers were the only four-strokes racing in F750 in the US. At the peak of their development they produced around 100 horsepower, and were probably the fastest pushrod twins ever.

Ian Falloon is one of the world’s foremost motorcycle historians and authorities on classic and collectable models. He has written several books on BMW, including The BMW Boxer Twins Bible and The Complete Book of BMW Motorcycles, both of which are available here.