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BMW Switches 4 Series Convertible To Performance-Enhancing Premium Soft-Top For 2021

BMW opted to use a soft-top on its all-new 2021 4 Series convertible coupe. Here's why performance enthusiasts will applaud the move.

The all-new 2021 BMW 4 Series Convertible coupe has launched. The big news is a switch from a retractable hardtop design to a new premium soft-top design. While every convertible top has its pluses, a well-made soft-top seems more fitting for this performance-oriented sport coupe. Here's why we feel the switch is the right move for BMW.

2021 BMW 4 Series Soft-Top Material and Construction
The new top is made from the Haartz Corporation's Sonnenland A5B/DS Acoustic topping, one of the highest-performing and highest-quality soft-top materials in the world. U.S.-based Haartz Corporation manufacturers its soft-top materials in the markets in which they are mated to the vehicle. In this case, the material is made in Haartz's Mannheim Germany facility. The Sonneland material is a high-performance, acoustically-enhanced, 3-ply topping with an acrylic twill weave facing, rubber inner-layer and a Polyester dobby backing.

BMW says that the new 4 Series Convertible's top uses large panel bow elements with a honeycomb-design construction, a flush-fitting glass rear window, multiple layers of insulation and a fabric cover available in two colors. The fabric is pulled taut when the roof is closed, giving the car a coupe-like appearance, but with a classic fabric top convertible feel.

Related: All Of Your Favorite Convertibles Have This One Important Thing In Common

2021 BMW 4 Series Soft-Top Colors
Soft-top roof color choices include standard black as well as an optional Moonlight black, which gives the fabric a classy metallic shimmer, especially in direct sunlight.

2021 BMW 4 Series Convertible Soft-Top Benefits Compared to a Retractible Hardtop
BMW points to the soft-top's performance-enhancing aspect, saying it is approximately 40 percent lighter than the previous generation’s hardtop. This results in a lower center of gravity for improved handling. BMW even claims that when the sleek new top is up, its smooth surface enhances the 4 Series Convertible’s aerodynamics (by 0.02 Cx) and reduces wind noise. Insulation allows for quicker heating of the cabin in colder temperatures.

2021 BMW 4 Series Soft-Top Convertible - Ease of Use
Opening and closing the soft-top only takes 18 seconds and can be performed at up to 31 mph. The top's three bow panels fold neatly into a compact Z configuration which can also be performed via the remote key thanks to the Comfort Access system which is standard on the M440i models and optional on the 430i models.

Cargo area is precious in every convertible, and hard tops typically require the most space. “The swap from a retractable hard top allows for more trunk space and a sleeker look when the top is down,” said Doug Haartz, international sales manager at Haartz Corporation. The more compact dimensions of the folded soft-top increased cargo area by 1.2 cubic feet over the previous 4 Series Convertible according to BMW.

To prevent damage to the roof or cargo, a mechanism prevents the top from being lowered if the trunk area is filled. A convenient pass-through door in the rear seat allows for longer items to be carried inside the car. Another benefit of the fabric top is a smidge more headroom when compared to the previous hardtop.

To reduce wind noise and turbulence in the cabin area, a standard wind deflector with two mesh elements can be fitted in the rear. When not in use, the deflector easily stores within reach of the driver behind the rear backrest or in its fitted bag in the cargo compartment.

2021 BMW 4 Series Convertible Safety
In addition to the usual suite of safety systems in the new 4 Series, the Convertible has a comprehensive rollover protection safety system. Two protective bars made from high-strength aluminum are triggered automatically the instant the central safety electronics indicate the car is at risk of turning. The rollover bars are out of sight behind the rear-seat head restraints. When the situation dictates, the pre-tensioned bars are extended by a pyrotechnic charge in a fraction of a second and combine with the strengthened windscreen frame to create a survival space for the occupants.

2021 BMW 4 Series Convertible - Pricing
Prices for the all-new BMW 430i Convertible start at around $55K. The 430i xDrive Convertible start at around $57K, and the M440i Convertible and M440i xDrive Convertible will approach $70K when outfitted with popular options.

Look for the all-new soft-top BMW 4 Series Convertible at your BMW dealer this fall.

John Goreham has owned both retractable hardtop convertibles and soft-top convertibles. John is a long-time New England Motor Press Association member and recovering engineer. Following his engineering program, John also completed a marketing program at Northeastern University and worked with automotive component manufacturers. In addition to Torque News, John's work has appeared in print in dozens of American newspapers and he provides reviews to many vehicle shopping sites. You can follow John on Twitter, and view his credentials at Linkedin

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COLX (not verified)    February 22, 2021 - 4:54PM

Aesthetically there is simply no comparison between the slick profile of the former version and the soft cover - the former hard top was unique and when closed it really made the car look a coupé. And the gain in the boot space is almost irrelevant. Most people point the front grille but the move to soft top is for me a big let down in the new 4 series cabrio