What you see here on these pages is the culmination of BMW's watershed between its long history of creating somewhat more sedate motorcycles for its loyal clientele who are older and more sophisticated (or as some derisively refer to as the "pipe and slippers crowd"), and the company's move toward attracting a younger, more performance-driven customer base that has traditionally been the backbone of the Japanese sportbike market. BMW management realized that its longtime customer base is rapidly aging itself out of the market, and that the real growth segment for the future is the sportbike sector. But the company isn't content to just dabble in the category with a half-hearted attempt and pick up the scraps left behind by the long-dominant Japanese manufacturers.
"We expect this bike's sales to be 90 percent 'conquest' sales-that is, a buyer who has previously owned another brand of sportbike," stated BMW Motorrad USA vice president Pieter de Waal, himself an avid motorcyclist. And part of that plan involves an MSRP not to exceed the average Japanese literbike price by more than $1000, another reason why this new model-designated the S 1000 RR-is not your typical BMW. This motorcycle isn't meant to be some sort of quirky alternative to the major sportbike brands; it is intended to go straight after those potential customers who have long been traditional Japanese (and/or European) sportbike buyers. BMW isn't asking for an invitation or trying to slip in a side door to the party-they're basically busting the door down and marching straight in.
Those of you chuckling at the thought of BMW making a serious sportbike that could challenge the established might of decades of performance R&D might want to reconsider that disdain. While we all know you can't ride a spec sheet, this new BMW's stats are nonetheless very impressive. And the company has come a long way since the days of the "flying brick" K-bikes of the past; its resume of racing and technological achievements in Formula One and other four-wheeled endeavors has become both extensive and impressive. And with its brand now firmly established as a performance model in the four-wheeled sector, BMW is looking to do the same on two wheels.
S 1000 RR
Rather than attempting to redefine the sportbike world with an alternative design, BMW went with the tried-and-true inline-four configuration for the S 1000 RR's powerplant. Although company engineers say they looked at other designs, there are many reasons why the inline-four has been the dominant engine concept in sportbikes (and racing) for years, and they couldn't ignore them. But, as per usual BMW practice, they've instilled their own brand of innovation into the design.
With its extremely large bore/short stroke measurement of 80mm/49.7mm, the S 1000 RR is the most oversquare engine in the literbike class, surpassing even the '09 Yamaha R1's radical 78 x 52.2mm configuration. The very short stroke means that very high rpm will be required to extract maximum power, and here BMW borrowed a design from its Formula One auto racing engine. Instead of running the camshafts directly over the valves and using valve buckets for actuation and lash adjustment, the RR's cams are positioned inward from the valve axes and utilize finger-type followers for valve control. Because the followers aren't totally reciprocating weight like valve buckets, BMW claims a near-50-percent reduction in reciprocating mass, which in turn allows more aggressive cam profiles without the risk of valve float at high rpm. Also, unlike conventional cam follower pivots that are always positioned outside of the cams, the RR's intake follower pivots inside the cam (making both intake and exhaust followers pointing rearward instead of each pointing inward toward the spark plug).
This valve-train design provides other benefits, including a straighter intake port angle at the valves, a tighter included valve angle, and shorter cylinder head overall front-to-back. Included valve angle is a steep 24.5 degrees (11.2 degrees intake, 13.3 degrees exhaust), with an intermediate gear between the crankshaft and cams shortening the cam chain drive's length for better timing accuracy at high rpm. The huge bore makes room for the largest valve sizes in the class, with the titanium intakes measuring 33.5mm and the titanium exhaust poppets coming in at 27.2mm. With such a steep included valve angle comes a low, flat combustion chamber resulting in a compression ratio of 13.0:1.