Earlier this week the BMW M4Convertible prototype with very little disguise and the top down wasspotted testing near the Nürburgring.

We were quite sure it is the last, or one of the last test runs before BMW makes it official. Here it is now in full glory with no big surprises compared to the M4 Coupe, except the retractable hard top with a different roofline.

The hard top lowers in 20 seconds at speeds up to 11mph and does make the convertible a bit heavier than the coupe, which does make it a bit “slower” than the coupe. The open top M4 is 250kg heavier than the coupe, weighing at 1,750kg, though still 60kg lighter than the previous model.

Luggage capacity is 370 litres when the roof is closed and 220 litres when it is stowed in the trunk. Thanks to improved insulation, the new model is up to 2dB quieter inside than the outgoing M3 Convertible.

Power comes from the same 425bhp 3.0-litre TwinPower Turbo six-cylinder with 406 lb-ft of torque with power sent to the rear wheels. With he standard six-speed the M4 Convertible goes from 0-62mph in 4.6 seconds and with the optional £2,645 seven-speed M Double Clutch Transmission in 4.4 seconds. The Coupe does it in 4.3 and 4.1 seconds. Top speed is limited electronically to 155mph.

The interior is identical to the coupe with its leather-wrapped sport steering wheel, sport seats, M gearshift and M-branded sill plates.

Other highlights include 19-ihch alloys, heated front seats, Bluetooth and USB, all round parking sensors, professional media package, Active M Differential, M compound brakes, M-tuned electromechanical steering system, and optional Adaptive M suspension (with COMFORT, SPORT and SPORT+ modes) and M carbon ceramic brakes with gold-painted calipers.

The M4 Convertible will debut later this month at the New York Auto Show.

Unfortunately you won’t be able to drive the new M4 Convertible this summer as it goes on sale in September with prices starting at £60,000.