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| BMW R1150GS – industrial strength dirt-digger |
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Dave Abrahams September 10 2002 at 04:05PM |
Get IOL on your mobile at m.iol.co.za |
When BMW introduced its first off-roader, the R80GS, in September 1980, the pundits said it was too big to ride well on dirt. They were wrong – since then the Blue Propeller Company has made every edition of its industrial-strength dirt-diggers bigger and heftier – and still GS fans ride them into (and out of) the world's most remote places.
This remarkably civilised big twin will pull without power-thudding from about 1500rpm in the lower gears and 2000 in top and tolerate full throttle from below four as it starts to pull strongly through to the red line at 7500rpm. The Bosch Motronic 2.4 fuel-injection system is well enough damped to deal with very slow riding (just as important in heavy traffic as it is in heavy bush), even if the chassis is a top-heavy. The spritzer set-up runs the bike very lean on overrun, for both cleaner emissions and better economy, but if you try to pick it up and ride away at very small throttle openings the GS will stall surprisingly easily and perhaps catch you unprepared. The single-plate hydraulic clutch is as before - it's the best dry clutch in the business - but the gear ratios have been revised, with first and sixth noticeably shorter. The ultra-low first gives a very authoritative pull away but the bike very quickly runs out of revs and requires a leap to second. The lever throw is a little too long and the revs drop alarmingly but the torquey motor soon yanks itself out of the hole and starts pulling like a steam train.
Top gear is an improvement on the more road-orientated version; there's enough grunt to go up hill down dale and into the teeth of the South-Easter without having to change down and the bike will still pull its top speed of 192km/h at just over seven, 500rpm before the red line. There's the usual BMW clonk from the final drive as you turn the power on and off; it's most pronounced in first but it's there in every gear if you listen. The motor vibrates strongly above 5500rpm and the most comfortable cruise was obtained at just under that - which translates to 145km/h in top. The chassis is unchanged except for the stork-like suspension though the one-piece bench seat is more comfortable than the two-section, height-adjustable item on the earlier model and has more room to move around on a long trip, even with two riders aboard. The seating position is (of course) very upright but, with adequate protection from the taller windscreen, air-blast is not a problem. Then screen is rubber-mounted and moves through a disconcertingly wide range at higher speeds; it will give you the willies until you get used to it but doesn't affect the bike's stability. Dismounting is like getting off a pony The suspension causes as many problems as it solves, unfortunately. The seat height is a nosebleed-inducing 900mm and most of the weight of the 30-litre fuel tank and its contents is even higher than that. Unless you have very, very long legs you'll be unable to put more than the tips of your toes on the ground; balancing this quarter-ton monster at a standstill requires concentration. I'm 1.78m tall and weigh 106kg and this bike is too big for me; whenever I had to paddle it around in a parking lot I put down the side stand, slid off like a child dismounting from a pony, and pushed it round … very, very carefully. BMW has an alternative saddle that is 40mm lower; a sensible choice unless you are an NBA candidate. 30 litres of fuel weighs around 25kg; I collected the Adventure from the local BMW dealer with a full tank (thanks, Freddie) and at first it felt like riding a normal bike with a pocket of cement sitting in my lap. I rode it for the first time in heavy traffic and even after I got used to it the bike showed a slight tendency to fall off to one side or the other at speeds below about 30km/h. It didn't self-stabilise properly until about 40km/h and keeping it on a straight line at walking pace in the Friday evening gridlock required constant attention. This was to be a recurring theme with BMW's heavy-duty beetle-crusher; its unwillingness to be ridden very slowly made it a bit of a handful in the dirt as well as in traffic. Astonishingly nimble Out onto the freeway and above 40km/h it's rock steady - right up to its top speed, apart from a slight nervousness in the steering at full blast, which is rider-induced via the very wide handlebars. For a 253kg motorcycle it's astonishingly nimble and can be thrown around like a sports bike while the tall slim chassis allows some serious angles of lean and the torquey motor blasts you out of corners hard enough to surprise riders of sports fours. The brakes, even without the optional ABS, are impressive. Twin Brembo four-pot callipers with 305mm stainless-steel discs up front haul the plot down with authority and the standard braided stainless-steel hoses give impressive bite when needed. I was expecting a fair amount of nose-dive, given the long suspension travel, but I reckoned without the Telelever front end and its inherent anti-dive geometry; under hard braking the front maintains its position while the back of the bike comes gently up off the ground in a neat little stoppie! The rear brake has more power than you'd expect on a road bike; it's useful for sliding the back wheel of this overgrown hooligan tool around in the dirt and for steadying the bike in rain. Telelever front suspension is known for its ability to soak up life's little hurdles while retaining excellent steering accuracy but the WP progressive rear monoshock is definitely a step up for BMW. The rear suspension, despite the unsprung heft of that huge final drive housing, gives an effortlessly smooth ride with no jarring or harshness. Off-road experts say that's what gives this machine its impressive mastery of the dirt; the trouble is that you have to be an expert to explore that side of its character. At my kind of dirt road speeds the GS is just too top-heavy, too unstable to be anything but thoroughly intimidating. I kept thinking "This thing's model designation should be PzKfW, not GS!" Centre stand - if you can The front suspension has one amusing quirk; it's absolutely stable under braking but an over-hasty downshift will cause the whole bike to dip slightly forward and to the right under torque reaction from the huge motor, like a pony trying to buck It's not enough to upset the composure of the chassis and, once I knew to expect it, it caused a grin every time. The GS comes with a centre stand but heaving the big Beemer up on to it is not for the faint of heart; it requires a certain knack, a fair amount of upper body strength and a modicum of body mass (the rider's, that is). Grab the rear sub-frame, throw all your weight on the foot lever and heave backwards for all you're worth. Getting the thing off the stand can be just as much of a mission and more than once I resorted to tipping the front wheel into the air and simply riding the bike off its stand. The detail work, as we have come to expect from Beem, is outstanding though idiosyncratic; the handlebars are assembled from three pieces with rubber sleeves between them – a form of rubber mounting that works. The instrument panel is the standard GS item, complete with the little rectangular panel on the left that rells coolant temperature, gear position, fuel level and the time of day in one compact liquid-crystal display. The switchgear is also BMW corporate pattern, superlative but retaining the company's famously silly indicator system that requires three switches to do what everybody else does with one. There's a 12-volt power socket on the fairing just below the handlebars for your GPS or laptop or phone charger and another on the starter motor cover for your heated suit. The underside of the motor is protected by a substantial aluminium bash-plate, bolted to a serious set of three-way engine protectors. Dark Chinese blue The mounting points for the pannier framework are readily accessible and the (optional) three tough aluminium boxes will hold an impressive 120 litres between them. The tops of the side panniers are level with the rear seat for easier packing of bulky touring items such as a tent. Practical accessories such as a stone guard for the asymmetric headlights and the fog lights are available. Visually the new GS is overwhelming; the matt-silver fuel tank is nearly a metre wide at its biggest, the screen stands shoulder high to a big man when the bike is on its centre stand and the seat is nearly a metre high. Bits stick out all over the place and it looks aggressive just standing there, ready to stomp all over some piece of real estate that thought it was wild country. The tappet covers are a dark Chinese blue and the alloy rims are anodised to match. That, and the clever pattern of edge-mounted spokes, not only makes it possible to replace individual spokes without removing the tyre but means they are easy to clean – an unexpected bonus from any bikemaker. My overriding memory of the GS Adventure is that it's too big. It's a very competent street bike, if you don't ride it too slowly, but then BMW has other, better light tourers that will cover that aspect better without perching you uncomfortably on tip-toe. In the dirt, it's an expert's weapon, capable of astonishing feats thanks to its centrally located major masses and torquey motor, but it has to be ridden hard to keep the plot together, harder than some of us chickens can manage. It's a handful in heavy traffic, yet superbly comfortable on the open road, but ironically those features which help to make it such a competent dirt-bike in expert hands (preferably ones with neither nerves nor imagination) also detract from its spectrum of performance on tar. Frankly, there are better all-rounders. As I said in the beginning, with this one BMW has reached the practical limit for a dual-purpose bike. Test bike from Auto Atlantic, Cape Town. Price: R105 500 (R113 900 with ABS and heated grips). Click here to use IOL Motoring's repayments calculator. For full specifications, click here
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