• It has been rumoured that the new R 1250 GS will be powered by a new Boxer engine with variable valve timing.

• A promotional video has surfaced online confirming the rumors.

• The video also illustrates how the “Shift Cam” technology works besides the look of the new GS.

It was hotly rumoured that the new 1254cc Boxer engine in the new 2019 BMW R 1250 GS will feature variable valve and cam timing but there was no concrete proof. But now, a promotional video has surfaced online which illustrates the new Boxer engine with “Shift Cam” technology, courtesy of Motocular.com.

The system aims to provide the best acceleration along with high power gains, while maintaining smooth power delivery, and lower fuel consumption as well as exhaust emissions to meet the tough Euro 5 standard.

To achieve those targets, the BMW Shift Cam system is simple, utilizing an intake camshaft with two cam profiles and a mechanical shift gate at one end.

At low engine loads (lower RPMs), the shift gate engages the camshaft and locks the low lift and short duration cam lobes over the finger followers. That way, both intake and exhaust vavles shut quickly for less overlap, promoting low-end torque.

Conversely, at high engine loads (higher RPMs), the shift gate… er… shifts the camshaft to present the high lift and longer duration cam lobes. Consequently, the intake valves shut later for more valve overlap timing, raising the engine’s power output.

It is the best of both worlds. (You may read more about valve overlap in this article.)

The new Boxer is claimed to produce 136 bhp and 143 Nm of torque, up from 125 bhp and 125 Nm of the present 1176cc engine.

Besides seeing how the new engine works, the video also revealed how the 2019 BMW R 1250 GS will look like.

As we have reported earlier, the new engine may also power the entire Boxer-engined line-up. The R 1250 GS and new models should make their first official appearance at the Intermot show in a few weeks’ time.