BMW is preparing the next generation 6-Series coupe and convertible. The official debut will be made in 2010 at the Geneva Motor Show with sales to begin later in the summer.

BMW did a good job of disguising this car for testing but it does reveal two new facts. First BMW will not be switching to a folding metal roof like it did with the 3-Series convertible, most likely for the weight savings. Also the design of the fabric top has changed. Gone are rear the flying buttresses with the flat glass back window that could be lowered independently of the roof, and now a more conventional setup is in place.

The 2011 6-Series should share the engine line-up with the 5-Series. Internationally BMW will use a revised versions of today’s six-cylinder gas and diesels, as well as V8 gas engines. We also expect a M6 version will follow in 2011 with a twin-turbo V8 engine.

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