BMW is introducing a new set of M Performance wheels for the latest M5, but the interesting part isn’t simply the design. The new 1075 M wheels use a high-pressure casting technique that BMW claims can reduce wheel weight by as much as 20 percent without sacrificing strength or performance.
The technology is making its automotive debut on the G90 BMW M5 Sedan and G99 M5 Touring, with the wheels offered exclusively for the two M5 models. Buyers will be able to choose between 20-inch and 21-inch sizes, finished in either Gold Bronze or Jet Black.
A New Way Of Making Cast Wheels
Traditional cast aluminium wheels are generally produced using low-pressure casting. Forged wheels remain the preferred route when reducing weight is a priority, but BMW’s new approach aims to narrow the gap while retaining the advantages of casting.
The High Pressure Casting process was developed by German company Entec-Stracon GmbH. Molten aluminium is forced into the mould under vacuum and extremely high pressure, with the wheel forming from the outside towards the centre.
The actual casting process takes just 0.05 seconds.
Around 80 sensors work alongside an AI-based monitoring system to oversee production, while the finished wheel can be removed from its mould within a matter of seconds.
Unlike conventional cast wheels, there is no need for a separate heat-treatment stage afterwards. BMW says eliminating this step helps cut the overall production time by around 50 percent while also halving the energy required to manufacture each wheel.
Up To 20 Percent Lighter
Speed isn’t the only advantage of the new manufacturing technique.
The rapid casting process produces a finer grain structure within the metal, increasing its strength. This allows engineers to make certain areas of the wheel thinner and lighter while maintaining the required structural performance.
BMW claims the result can be a weight reduction of up to 20 percent per wheel compared with conventional production methods.
The manufacturer hasn’t revealed the actual weight of the 1075 M wheel, however, nor has it specified the exact wheel against which that 20 percent saving is calculated.
Considering the latest M5 weighs roughly 2,445 kg, shaving mass from the wheels is certainly no bad thing.
Why Lighter Wheels Matter
Reducing wheel weight is particularly useful because wheels form part of a car’s unsprung mass.
The suspension has to manage that weight whenever the car encounters bumps or changes direction. Wheels are also rotating components, meaning the drivetrain needs to accelerate them and the brakes need to slow them down.
BMW says the reduction in unsprung mass contributes to more agile handling, stronger acceleration and improved braking performance.
Whether the difference will be obvious from behind the wheel remains to be seen. Without knowing the actual weight saving of a complete 1075 M wheel, it’s difficult to quantify how significant the improvement will be.
More Freedom For Wheel Designers
High Pressure Casting also gives BMW’s designers considerably more freedom than traditional low-pressure casting.
According to BMW, the process can accommodate designs with as many as 70 blade-style spokes, exceptionally thin sections to improve aerodynamics and much finer surface details and contours than were previously practical with a cast aluminium wheel.
That doesn’t mean the new 1075 M wheel uses all 70 spokes. Rather, BMW is highlighting what the manufacturing technology could allow for future wheel designs.
The wheels use what BMW describes as an optimised and recyclable aluminium alloy.
BMW M5 1075 M Wheel Options
The new M Performance wheels will be offered in the following configurations:
- Sizes: 20-inch or 21-inch
- Finishes: Gold Bronze or Jet Black
- Package: Complete wheel set fitted with sport tyres
- Fitment: G90 BMW M5 Sedan and G99 BMW M5 Touring exclusively
BMW has not yet announced pricing or confirmed which sport tyre will be supplied with the package.
The technology itself is arguably more interesting than the first wheel to use it. If BMW can deliver meaningful reductions in weight, energy consumption and production time without moving to significantly more expensive forged construction, High Pressure Casting could eventually find its way onto considerably more BMW M products.
