The BMW 6-series convertible put on 39mm of width (to 1895mm) and 74mm of length (4897mm) in the transition from second to this third generation model when it was introduced in 2011. Its body-in-white is predominantly high-strength steel but was reinforced in key areas; it’s 50 per cent more torsionally rigid than the previous car’s.
The 6-series’ long wheelbase and its profile with that long bonnet and rear-biased cabin are all visual styling hallmarks to which BMW lays proprietorial claims, particularly for its convertibles.
It is a profile that has incorporated four doors very successfully with the Gran Coupe, producing one of BMW's most aesthetically pleasing cars from recent times. Despite being based on a unique platform that adds another 113mm to the wheelbase, the Gran Coupe is successful as an elegant four-door coupe, rather than appearing like a saloon with a lowered roofline.
Surface sculpting in the 6-series’ metalwork is supposed to represent the movement of waves of water flowing from the bow of a motor boat.
If you're not paying quite such close attention, the headlamps and LED daytime running light design are meant to give the car a recognisable BMW visual character even in the rear-view mirror, even at night; while an upright kidney grille and prominent surround are nods to the original 6-series’ shark nose. Pedestrian protection regulations rule out any closer recreation. To boost safety credentials, that long bonnet pops up in a frontal collision.
On the convertible, it's worth noting the heated glass rear window is separate from the folding roof. It can be lowered to create a gentler ventilation than an open side window when the hood is up, or it can stay up with the roof down to reduce buffeting.