According to AutoBild, the 9 Series will be based on a stretched version of the 7 Series's platform, and will have a unique body inspired by the Vision Future Luxury concept, which was unveiled at the 2014 Beijing motor show.
Comfort for rear seat passengers will be paramount. Those sitting in the back will be treated to individual seats, and individual entertainment screens, while ingress and egress will be via rear-hinged doors.
Engine choices are said to include the company's twin-turbo 6.6-litre V12. That engine is currently used in the BMW's current range topping sedan, the M760Li xDrive, where it generates 441kW of power and 800Nm of power, and drives all four wheels via an eight-speed automatic.
Above and top: 2014 BMW Vision Future Luxury concept.
The 9 Series could also be offered as a plug-in hybrid. If that comes to fruition, expect it to be more powerful than the 240kW/500Nm PHEV drivetrain in the 740e, which pairs a 190kW/400Nm 2.0-litre turbocharged four-cylinder engine with an 83kW/250Nm electric motor built into the eight-speed automatic transmission.
Like today's 7 Series, the new 9 Series will have a body that uses a mix of steel, aluminium and carbon-fibre. With the 9 Series, the usage of carbon-fibre could increase to include the seat shells and more body elements.
This latest rumour about BMW's future product plans comes just days after reports stated that the 6 Series will be replaced a 7 Series-based 8 Series range, and that an X2 'SUV coupe' will make its debut at this year's Paris motor show.
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