World-Exclusive ride report on the K 1200 S
Das Motorrad: July 17, 2004
Written by:Michael Pfeiffer
Photos by: BMW factory
BMW enters the Sport arena. But not simply with a clever copy of Japanese design, rather with the technologically advanced K 1200 S. MOTORRAD rides the most powerful non-Japanese production machine of all time.
The new BMW has gotten very long, and narrow. Longer than all other four-cylinder sportbikes on account of the 55 degree forward angle on the cylinder block, but narrower than most through the extremely slim and compact design of the motor. Although the machine is just like all the Japanese bikes, in that the motor is installed with the crankshaft across the frame, the bike remains a typical BMW.
Shaft drive, single-sided swingarm, standard equipment ABS, blinker switches on the left and right handlebars, all things that you find only on bikes from Munich. Above all, the unique design; sporty, understated, cleverly hiding the unusually long wheelbase of the bike.
The giant muffler tucks in closely to the 6.00 rear wheel, and has a clean look. The new double leading-arm front fork is almost completely hidden by the fairing, which sticks out quite far in front.
Compliment: The BMW engineers have build a revolutionary front end, and one can barely see it. Only the nearly horizontal main frame rails, running above the motor, and the wheel carrier, a wonderfully confidence-inspiring casting, bear witness to the completely innovative design of the chassis. All well and good, but how will this completely new chassis perform?
Next, to the motor: The brand-new 1157cm motor is certainly not subtle. It immediately settles into a lightly rhythmic idle and rumbles deeply out the tailpipe.
A few twists on the throttle makes it clear; this is a high-output motor that has nothing in common with the previous K bike powertrain. The new powertrain gives a snappy response to every throttle movement, and sounds like something between a Kawasaki ZX12R and a Honda CBR1100XX
Climb on, drive away.... the controls feel as though they are fitting themselves perfectly to hand, somewhat slim grips on the not-too-narrow handlebar, and the feet fit perfectly on the comfortably-arranged footpegs. The upper body is stretched a little bit far over the tank, nevertheless the ergonomics fit very well.
Especially well, because the shape of the tank makes possible a perfect fit bewteen rider and the machine. The clutch takes a powerful grasp, first gear is noticeably noisy in engagement. But we are already familiar with this characteristic from the Japanese.
Already in the first few meters underway you can forget about the fully-tanked 248 Kilos weight of the BMW. First, it lets itself be steered practically with the lightness and responsiveness of a 600. The second thing which strikes the rider immediately is that the front suspension filters out all the unevenness of the road. The refinement of the suspension, called Duolever and invented by the British Norman Hossack, is inspiring. The third thing, the K1200er gets right down to business.At low rpms it doesn't quite have the impact of a Yamaha FJR 1300 or Suzuki Hayabusa, but nevertheless it pulls mightily! In spite of two balance shafts it does vibrate, sometimes more, sometimes less, according to load. Not particularly disturbing, but noticeable. From 6,000 rpms it really takes off!
Finally an opening on the Autobahn! A chance to run out the 167 horsepower. The four-cylinder growls, spins up to 8,000 rpm and catapults the BMW brutally forward. Third gear, fourth, fifth, this thing is really going somewhere! Never before such a speedy BMW; 250 km/hr was the fastest we saw on the K 1200 RS. The S surpassed this mark on the easy-to-read speedo with plenty of acceleration left in fifth gear. The new bike accelerates until over 280 km/hr, then the tachometer needle climbs into the red zone... in other words perfect gearing.
And thanks also to the incredible protection of the fairing, developed in the wind-tunnel, this speed is quite easily bearable, without trying to make yourself as small as possible.
Why does the motor of the K 1200 S develop such great power? The extremely compact combustion chambers, the included angle of the valves at 21 degrees, and the cylinder-selective knock-sensor allows this, since the motor can get away with a fabulously high compression ratio of 13 to 1. Straight inlet ports, respectable 46mm throttle bodies, and an airbox that uses air pressure at high speed (ram air) in the inlet tract to boost cylinder filling all bring extra power to the motor. When you can't fill up with super premium the knock sensor retards the timing to safer levels and reduces the power output to healthier values. The rear tire gets mistreated with a few less horsepower than the listed 167 PS. For now, the good Super Plus is in the 19 liter (5 gallon) tank, and all the ponies are getting to the rear wheel. At the very topspeed, the BMW does not feel completely stable, the handlebar is a little disturbed by concrete seams and joints.
Only 500 meters from the exit, full on the brakes! It is brutal, how the BMW reacts to hard braking. The ABS with power assist, the stiffness of the Duolever front end with no brake dive, and very low center of gravity make for spectacular deceleration. A real advantage when things get tight. And it is good that the system is only partially integrated, so that the rear brake alone can be activated by the footpedal. That makes it easier to "anpassungsbremsen" , as one often unconsciously does before a turn.
Finally, some curves! In spite of the giant wheelbase of 1571 millimeters, the 60.6 degree steering head and the respectable 120 millimeters of trail, the K 1200 S handles so much more easily than others in its class. The center of mass must be very low. Thanks to dry-sump design, alone among others in its class of big four-cylinder motors to use this system, the drivetrain can be installed 60 millimeters lower than would be possible with an oilpan below the motor. At the same time the riding comfort is astounding, the springing and damping ironing out all the bumps as though the road were completely flat. Even more impressive than the effect itself is a glance at the action of the wildly scissoring steering linkage in front of the ignition lock. Does this road really have so many bumps? The rider feels virtually nothing but perfect smoothness. A completely new kind of riding feeling.