BMW recently debuted their new flat-twin-cylinder motorcycle engine at the Cologne show. Rumors and spy photos gave a reasonably accurate picture of the new powerplant; bikes powered by it will be launched next year.
Though it will eventually be offered in a range of displacements, the version shown displaced 1085cc, via a 99mm bore and short, 70.5mm stroke. Cooling is by air, assisted by strategic oil flow within the engine. Camshafts are carried high in the head, but this is not a true overhead camshaft design; much like the Moto Guzzi Daytona engine, the cams actuate four valves per cylinder through very, very short pushrods and long rocker shafts. Still, that's a huge improvement over the centrally mounted single camshaft and more than foot-long pushrods of the old twin, and BMW claims outstanding power output: 90 horsepower at 7200 rpm, with 90 pound-feet of torque at 5500 rpm. And that's with a catalyst in the exhaust system!
Fuel injection allows a very compact intake system, with the port twisted upward to keep the hardware well away from a rider; so ends an identifying mark of long-time BMW riders: black and blue shins.
In the past, BMW officials have mentioned the new engine may see a BMW return to racing. While the R259 might not be competitive in 1000cc racing form in World Superbike events, it's more promising for Battle of the Twins, which continues overseas if not in the U.S. And doesn't the AMA allow 1200cc pushrod twins in American Superbike races? Might be interesting . . .