The Specs
The architecture of BMW's new sportbike resembles the major Japanese players in every conceptual area. There's an across-the-frame inline four-cylinder engine with double overhead cams and 16 valves. There's a six-speed transmission with a chain final drive.
The frame is an aluminum double-spar structure typical to the genre, and the suspension uses straightforward telescopic forks and a beefy alloy swing arm with a single-shock rear linkage. In silhouette, the new BMW S1000RR looks very much like its Asian counterparts.
The differences lie with BMW's calculated attempts to beat the opposition. The bike's face is asymmetrical because, BMW says, using one headlight for high beam and another for low beam is lighter and takes less space. The fairing is different from side to side because there were different airflow challenges to be met at each side.
With a claimed 193 hp at the crankshaft, BMW's new superbike has more power than the opposition and about the same as the King Kong, the Suzuki Hayabusa, a 1.3-liter bike that has a third more displacement. A radically oversquare bore-to-stroke relationship (that means the diameter of the piston is greater than the stroke) facilitates very high engine speeds, abetted by light finger followers in the valvetrain—borrowed directly from F1 practice—that dramatically reduce valve reciprocating mass.
A trick exhaust-header system employs interconnecting pipes and valves to exploit supportive resonances, fattening the torque curve. Moreover, with available full race antilock brakes (ABS) and multi-level dynamic traction control (which uses a lean angle sensor to automatically dial the power back when the bike is heeled over in a turn), the bike brings more of BMW's involvement with F1 and World Superbike racing to the street rider.
Another worthwhile addition is BMW's optional speed-shift system, which allows you to stay at full throttle when making upshifts. A switch on the shift lever cuts engine power briefly to permit quick and seamless upshifts without recourse to the clutch.
The Ride
We started off in Rain mode, accessed by a button on the right-hand bar. The mode cuts power output to 150 hp, lowers the engine-speed limiter and shift-light warning, and provides the most aggressive traction-control intervention. When the lean-angle sensor signals any angle greater than 38 degrees, the fly-by-wire throttles back off to a preset position—dependent on vehicle speed—to optimize tire grip.
In Rain mode the bike is pretty much like a 750 with electronic nannies looking out for the rider. The provision of this mode has provided justification for the use of this bike as a school mount for the Keith Code California Superbike School—the first ever to use a multi-cylinder liter bike in that role. If you tip into a corner in Rain mode you can feel the power come in and go out according to the bike's lean angle.
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