1600 cc six-cylinder in-line engine
This 1,649 cc power train, a development by BMW, provides 160 hp at around 7750 r.p.m. and a maximum torque of around 129 lbs-ft at around 5250 r.p.m. From 1500 r.p.m. upwards, more than 70 percent of the maximum torque is already available. This enables gentle cruising as well as superior sport driving.
The in-line six-cylinder engine weighs a mere 226 lbs., including alternator, intake system, clutch and gearbox. The consistently lightweight design, due to its hollow camshafts for example, makes it the lightest six-cylinder in-line engine currently available in series motorcycle construction. And its width of 555 millimeters is around 100 mm less than even the most compact series-production, six-cylinder in-line motorcycle engines available previously. Its low construction width has been attained above all due to a slightly subquadratic stroke/bore ratio of 67.5 to 72 millimeters (0.938) with a relatively long stroke and very short distances between cylinder axes of 77 millimeters. In addition all electrical sub-assemblies are located behind the crankshaft in the available free space above the gearbox.
Like with the current BMW four-cylinder engines, the cylinder bank is inclined to the fore by 55 degrees. This results in a low center of gravity and balanced distribution of weight. The integrated dry-sump lubrication, which renders a conventional oil sump with an oil reservoir superfluous, enables a lower installation position. This inclination also creates space for an aerodynamic intake system directly above the engine.
The efficient combustion, low speed level with high acceleration speeds and minimal friction result in a six-cylinder motor with an extremely high efficiency rate and hence a suitably low, contemporary consumption. Bearing in mind this performance potential, the engine attains top marks in this area with levels that are comparable with a four-cylinder motorcycle.