Bmw K1100rs
BMW K1100RS
CYCLE WORLD TEST
AFTER NINE YEARS, A WORLD-CLASS K-BIKE
IF ANYONE UNDERSTANDS THE CONCEPT OF SPORT-TOURing, it's the folks at Bavarian Motor Works. After all, BMW practically invented the concept, offering purpose-built sport-touring machinery as far back as 1976, the year it introduced the R100RS Boxer Twin and planted the seeds of a two-wheeled category that has grown steadily since.
For 1993, BMW hopes to further that growth-and extend its own influence in the sport-touring market-with the introduction of the K1100RS, a machine that is arguably the most technologically advanced K-bike ever to emerge from BMW’s Berlin factory. The U.S. unveiling of the new RS comes just weeks after the world launch of the new-generation RI 100RS Boxer (see Cycle World, May, 1993). Pulling the wraps off a pair of machines as significant as these two within a month of one another may seem out of character for a company as traditionally conservative as BMW. But the move is a clear signal that BMW’s two-wheeled division is alive and well, and very serious about its long-term presence in both the U.S. and world markets.
Although K-series machines have endured criticism since their introduction and have not sold in the numbers originally intended, BMW brass says continued development of the K line and the introduction of the updated Kl 100RS makes perfect sense. The company’s overall worldwide sales increased by 4 percent last year, and with more than 35,000 units sold, 1992 was the division’s best sales year to date. In the U.S., BMW’s market share in the over-700cc category—though tiny compared to that of the Japanese makers and Harley-Davidson-inched upward in ’92, a trend that has the company looking to the future with optimism.
“The K-series machines broaden BMW’s appeal, said a company spokesman at the Kl 100RS s U.S. intro. The RS version of the K-series line, for instance, has accounted tor roughly 15 percent of our overall sales worldwide since its introduction. There’s definite demand for the design.”
It wasn’t always that way. Introduced to the U.S. market in 1984, the first-generation K-bikes offered unique qualities and decent performance, though less-than-endearing traits such as excessive engine vibration, underdamped suspension and a hyperactive final-drive system kept the line from reaching its full potential.
BMW addressed each of those problems in ’91 with an updated K100RS, which offered the 16-valve cylinder head, Paralever rear end, upgraded brakes, electronic engine management, and reworked frame and suspension, all taken from the avant-garde Kl sportbike. The mods boosted the RS’s performance and reputation significantly, though with new competition from Japan, namely Honda’s class-leading STI 100, there remained plenty of room for improvement, especially with regard to engine performance.
During the early stages of the new RS’s development, engineers focused their efforts in basic areas. Engine power and torque would be increased for added straight-line and two-up performance. Rider and passenger comfort would also be improved, along with an increase in wind and weather protection.
Bestowing serious horsepower upon the RS turned out to be a simple affair, and involved nothing more than the use of the hot-rodded engine that currently powers the Kl 100LT tourer. Producing a claimed 100 crankshaft horsepower, the LT’s liquid-cooled, dohc, inline-Four is based on the triedand-true K100 engine, though in LT and RS trim it features a 3.5mm (106cc) bore increase and breathes through 16 valves. To reduce engine vibration, the 1093cc powerplant uses lighter pistons and slightly longer (by 6mm) connecting rods than the old-style engine. BMW says the vibration reduction stems from a decrease in the engine’s reciprocating mass. The rest of the RS engine is pure Kseries, the same basic, on-its-side design BMW has used since ’84.
After outfitting the RS with an up-to-snuff engine, BMW looked to improve overall rider and passenger comfort, and wind and weather protection. The wind-tunnel-designed sport fairing fitted to the RS since its inception offered decent upper-body protection, though a revitalized RS would require a more fully shielded cockpit if it was to compete with machines as competent as the Honda STI 100.
To that end, a new lower fairing/engine cowl was developed;
BMW claims it offers improved leg protection, and though the rounded shape of the lowers contrasts with the RS’s sharply molded bodywork, the end result is pleasing to the eye.
To further enhance comfort, the RS features a slightly wider handlebar than that fitted to the K100RS, as well as vibrationdamping handlebarand enginemounts. Bar-end weights are fitted to further quell buzziness.
An isolated footpeg-mounting system also helps fight vibration.
Rounding out the RS’s list of new features is additional frame gussetting beneath the fuel tank (to handle the increased engine output and cornering loads), thicker exhaust headers (for increased durability), a beefier battery and charging system, a four-way adjustable front-brake lever, newly designed handgrips and, according to BMW, a 7-percent increase in fuel economy compared to the K 100series machines.
Climb into the RS’s cockpit and, if you’ve spent any time aboard a BMW K-bike, you’ll feel instantly at home; the bike’s switchgear, instruments, mirror placement and overall layout are typical K-bike fare. Thumb the “choke” lever and depress the starter button, and the RS lights quickly, its Bosch Motronic engine management/fuel-injection system delivering the precise amount of fuel-air mixture to each combustion chamber. From the saddle, engine noise is muted, the characteristic gear whine the most noticeable sound to reach the cockpit.
The RS’s riding position is roomy and well designed; there’s plenty of seat-to-peg distance to keep legs from cramping, and the reach to the nicely curved handlebar is relatively short.
Throttle response is crisp, though compared to a typical Japanesedesigned engine, the Kl 100 motor revs more slowly Control effort is light and fluid, and only the slightest nudge on the shift lever is required to engage first gear.
The RS’s lowspeed manners are only fair, mainly due to its 564-pound weight, relatively narrow handlebar and longish, 61.6-inch wheelbase. Once up to speed, the RS begins to come into its own, offering the rider a solid base from which to operate. Once you’ve learned the bike’s unconventional switchgear—which feels strange initially but soon becomes second nature—you quickly realize that spending an afternoon in the RS saddle is a nice way to pass the time. The 42mm Marzocchi cartridge fork and the preloadand rebounddamping-adjustable Showa rear shock are sprung and damped well for a wide variety of riding situations, and provide a compliant-yet-controlled ride, with little of the pogo-stick shenanigans typical of old-style K-bikes. The Paralever system helps, of course, canceling the rising and falling motions that accompany throttle modulation on shaftdriven bikes. The RS’s saddle is quite comfortable, well up to 500-mile days. Passenger accommodations are a little more cramped, though the pillion seems couch-like compared to the rear perch of most current sportbikes.
At speed, the RS shines, devouring miles easily and confirming its autobahn heritage through its rock-steady highspeed stability. The RS makes perfect sense at speeds well above the national speed limit. Below 65 mph, the windblast glancing off the windscreen can be noisy and turbulent; above 80, the still-air envelope expands, leaving averagesized riders in a relatively turbulent-free cocoon. Elevated speeds also reduce vibration levels, especially between 65 and 80 mph. Stay within that sweet spot and the RS runs silky-smooth; ride below or above that point, and vibration creeps into the seat, bar and pegs.
In terms of engine performance, the RS proved surprisingly able, sprinting the quarter-mile in 11.71 seconds at 115.83 mph; those numbers won’t win you many drag-racing trophies, though they are significantly better than those of the ST 1 100 (12.20/111.11). The RS recorded a top speed of 139 mph, 8 mph faster than the Honda. The RS’s roll-on numbers were similarly better than the Honda’s, taking 3.5 and 3.5 seconds to accelerate from 40-60 and 60-80 mph, respectively, compared with the Honda’s 4.6and 5.1-second showings The only serious chink in the RS’s armor shows up during aggressive backroad assaults, especially those involving lessthan-smooth tarmac. The problem lies not with the excellent Brembo brakes, the sticky Bridgestone radiais or the RS’s conservative chassis geometry and relatively slow steering manners; the RS’s legs are the culprits here. For most situations, the bike’s non-adjustable fork and single shock do an admirable job of blending compliance and wheel control, but they simply don’t offer enough firmness and rebound-damping to cope with aggressive, cut-and-thrust maneuvers. The RS can be ridden surprisingly quickly down a twisty stretch of asphalt, though doing so demands skill and a hefty dose of smoothness.
As always, BMW motorcycles offer an array of intelligently designed features. The redesigned saddlebags, which are optional on the RS and retail for $686 (with mounting kit), are arguably the most functional hard bags available; they not only swallow a ton of gear, they’re durable, simple to install and remove, and lock and unlock with the ignition key. An extensive, 16-piece tool kit is also standard, as is a tire repair kit and BMW’s three-year, unlimited-mileage warranty.
The price of all this polished, German performance? A lot. $13,990 to be exact, a price tag that not only doesn’t include luggage, but is roughly equal to the price of the all-new RI 100RS Boxer, a bike that’s likely to compete directly with the K-series machines.
Still, you do get a lot for your money. You get a machine that can run head-to-head with the best in the class. You get the benefit of ABS, as well as the satisfaction of knowing your catalytic-converter-equipped machine is contributing only minimally to the Earth’s pollution problem. Best of all, perhaps, is the knowledge that you own a highly individual motorcycle, one designed and built by people who understand well the concept of sport-touring.
The KllOORS s high level of competence proves that point nicely.
BMW
K1100RS
SPECIFICATIONS
$13,990
EDITORS' NOTES
FROM AN AESTHETIC STANDPOINT, I HAVE always loved BMW's K100RS. But functionally, the bike's underpowered engine, excessive vibration, under damped suspension and high price left me disillusioned. Not so with the Motor Works' latest offering. This new K1100RS, with its in creased displacement, improved weather protection, updated ergo
nomics and fresh lines, is a wonderful motorcycle. True, a bit of vibration still reaches the handlebar, and the rider’s lower left leg still bakes on hot days due to its proximity to the 4-into-l exhaust. But otherwise, the Kl 100RS is nearly perfect. The well-thought-out gauges, strong Brembo brakes, comfortable-yet-sporting seating position, terrific hard luggage and quality Bridgestone tires make for one fantastic motorcycle. Yes, $14,000 is a lot of money, but for the serious sport-touring enthusiast, the Kl 100RS is well worth the price of admission.
-Matthew Miles, Associate Editor
I’VE RACKED UP A BAZILLION MILES aboard BMW Ks, most of which have been quite memorable. I did an eightday trip on a K75 through Germany, Austria and Italy at that bike’s press launch; I spent two weeks traversing the Alps aboard an ABS-equipped K100; and I’ve done numerous longdistance treks here at home aboard inline-engined Beemers. Despite their
oft-mentioned quirkiness, I find K-bike travel unique, entertaining and enjoyable, though I’ve always wondered just how good a K-bike would be with quality suspension, more power and less engine buzz.
Pretty damn good, as it turns out. BMW’s updated K1100RS is not only the most competent German sporttourer ever, it ranks right up there with Honda’s STI 100, sport-touring’s current Best In Class. For years, BMW has boasted about the proficiency of its K-bike line; with this new RS, it finally has a machine to back up those claims.
-Mitch Boehm, Managing Editor
HAS SOMEBODY BEEN SPIKING THE CORporate water-cooler over there at Bayerische Motoren Werkel First comes the K1100LT luxo-tourer, the first real alternative to Honda’s Gold Wing in years, then the tarp is pulled off the stunning, innovative RI 100RS sport Twin, and now we have the Kl 100RS, which has finally been given the improvements it’s needed for
almost a decade. Careful, BMW, with all this model renovation going on, you’ll give people the idea that you actually want to sell some motorcycles.
Past RS K-bikes have been seriously flawed. Take your pick: smoking engines, toe-numbing vibration, sub-600class acceleration, orange-peely paint that would have looked out of place on a Tijuana taxi, let alone a supposedly world-class sport-tourer. This new bike does away with all that. Yes, it’s still expensive and, yes, it still throws off a lot of heat in stop-and-go traffic, but this is a four-cylinder Kbike I would consider owning, and that’s something I never thought I'd say.
-David Edwards, Editor-in-Ghief
