2021 BMW M4 Convertible revealed in patent images

The upcoming 2021 BMW M4 Convertible has leaked in patent filings, ahead of its expected unveiling in the coming months.

Patent images filed with the European Union Intellectual Property Office – and unearthed by members of the i4talk forum – reveal BMW's hi-po drop-top is set to combine the standard 4 Series Convertible’s softened shape with the controversial front end and aggressive styling elements of the latest M4 coupe.

The G83-generation convertible’s nose is all-but-identical to the coupe unveiled in September, featuring its slim LED (or laser) headlights, tall kidney grilles, sculpted lower intakes and side air curtains.

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Changes compared with the coupe are a touch more pronounced at the rear, with the convertible’s folding fabric soft-top forcing the integration of a third brake light into the rear bootlid.

The repositioned central brake light likely accounts for the M4 Convertible's omission – according to the patent images, at least – of the coupe's rear lip spoiler, typically mounted to the trailing edge of the bootlid and finished in black.

The M3 sedan and M4 coupe's aggressive rear diffuser and quad tailpipe setup also feature on the convertible.

While the drop-top's cabin isn't pictured in the patent images, expect an identical interior to that of its fixed-roof, two- and four-door siblings, with large infotainment and instrument cluster displays, a plethora of M4 badges and the option of carbon-fibre bucket seats.

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Powering the M4 Convertible will likely be the same 3.0-litre twin-turbocharged 'S58' inline-six as its relatives, available in 353kW/550Nm 'base' and 375kW/650Nm Competition states of tune.

Drive is fed through a standard-fit six-speed manual in base variants, or an eight-speed automatic in flagship Competition models. Rear-wheel-drive is standard on the M3 sedan and M4 Coupe at launch, with an xDrive all-wheel-drive system to become available for Competition variants by late 2021.

However, some insider sources point to a sole powertrain being offered with the soft-top M4, reportedly the range-topping, all-paw Competition xDrive configuration which, despite its folding roof, would allow the M4 Convertible to extract its performance in all weather conditions, from its 'native' summer days to snowy northern-hemisphere winters.

For comparison, the outgoing, F83-generation BMW M4 Convertible – global production of which ended in October 2020 – sought power from a 3.0-litre twin-turbocharged 'S55' inline-six, developing 317kW/550Nm and 331kW/550Nm in entry-level and Competition guises respectively.

Outputs in both models were sent through a choice of six-speed manual or seven-speed dual-clutch automatic gearboxes.

The 2021 BMW M4 Convertible is expected to make its public debut in the coming months, with production rumoured to start in July 2021.

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