BMW M4 Competition Convertible 2021 UK review

How much of a driver’s car remains when you take the roof off the M4? First, it was the manual gearbox that fell by the wayside. Then it was rear-wheel drive. So your only choice for a BMW M4 Convertible today is a four-wheel-drive automatic. And you know what? That’s great.The powersliding enthusiast can still buy a rear-drive coupé, or just put the xDrive system in rear-wheel drive mode, and the purist is likely to be catered for by the upcoming M2. What you’re left with is a drop-top M4 in the spec that most people were going to order anyway.The big news with the convertible M4, or to give it its full name, the M4 Competition M xDrive Convertible, is the same as with the regular 4 Series Convertible: gone is the metal folding roof. Instead, you get a fabric top. You might hope that saves weight, and BMW does claim the roof itself is 40% lighter than the old model’s. However, because the 4 Series has grown so much and gained that four-wheel drive system, the whole car is actually heavier than before, weighing a portly 1920kg. That’s also 145kg more than an M4 xDrive Coupé. More so than the weight, the fabric roof benefits the styling. Since the boot no longer needs to hold three metal roof sections, the whole rear deck can be lower, more shapely and more like the coupé. The roof itself can also have a more attractive shape. Indeed, in the metal, it’s quite an elegant shape and a lot sleeker than the slightly saloonish old model. And yes, it has The Grille. Has enough time passed yet that we can admit it looks quite good? The fabric roof also enables more boot space – up to 300 litres when the top is folded, 80 more than in the old model. When the roof is up, that increases to 385 litres. As with most convertibles, the majority of the additional weight comes from bracing to get back some of the fixed-roof equivalent's torsional rigidity. As such, the M4 has an aluminium shear panel in the front-end structure, underfloor bracing elements and a rear axle subframe with a rigid connection to the body.Power is provided, as in all other M3 and M4 versions, by the familiar 3.0-litre straight six with 503bhp at 6250rpm and 479lb ft at 2750-5500rpm. Despite the weight, it still powers to 62mph in a faintly ridiculous 3.7sec.