BMW M rotor design

[AustinGelbM4]

Can anyone explain or link a good explanation of the BMW M rotor design engineering that uses 16 pins to hold the rotor to the hat? I don't see it in use by anyone else. How do those pins works? How are the brakes made?

[TractionControlDelete]

Originally Posted by AustinGelbM4

Can anyone explain or link a good explanation of the BMW M rotor design engineering that uses 16 pins to hold the rotor to the hat? I don't see it in use by anyone else. How do those pins works? How are the brakes made?

It's what some manufacturers call a pin drive rotor. SHW is one of those companies that make a similar type of rotor as the BMW one. For context, the BMW one is not a fully floating system but the below information may be helpful for your edification. They describe it like this:

"Pin-Drive system that offers unique benefits when compared to conventional disc brake rotor design. The Pin-Drive system consists of a two-piece, fully floating disc brake rotor with the friction ring connected to the central aluminum rotor bell by stainless-steel pins which are cast into the assembly during the manufacturing process.

By offsetting the pin connection of the friction ring to the aluminum bell, the cooling channels running centrally through the rotor offer an increase in cooler air flow – up to a 50% cooling advantage over traditional designs. Because air flow is paramount to performance, the lower the operating temperatures the higher the performance.

Features and Benefits:

Up to 5.5 lbs of weight reduction (rotating and unsprung weight) per disc compared to monoblock rotors
Reduced thermal strain thanks to the friction ring having more freedom to expand and contract
Reduced brake fade
Improved durability
Enhanced brake comfort thanks to optimized thermal conditions
Curved vane design maintains structural strength while improving noise dampening"

Here is one, for example, that is a direct replacement for the F87 M2 CS:

https://www.fcpeuro.com/products/bmw...r-shw-bfl48251

[AustinGelbM4]

Originally Posted by TractionControlDelete

It's what some manufacturers call a pin drive rotor. SHW is one of those companies that make a similar type of rotor as the BMW one. For context, the BMW one is not a fully floating system but the below information may be helpful for your edification. They describe it like this:

"Pin-Drive system that offers unique benefits when compared to conventional disc brake rotor design. The Pin-Drive system consists of a two-piece, fully floating disc brake rotor with the friction ring connected to the central aluminum rotor bell by stainless-steel pins which are cast into the assembly during the manufacturing process.

By offsetting the pin connection of the friction ring to the aluminum bell, the cooling channels running centrally through the rotor offer an increase in cooler air flow – up to a 50% cooling advantage over traditional designs. Because air flow is paramount to performance, the lower the operating temperatures the higher the performance.

Features and Benefits:

Up to 5.5 lbs of weight reduction (rotating and unsprung weight) per disc compared to monoblock rotors
Reduced thermal strain thanks to the friction ring having more freedom to expand and contract
Reduced brake fade
Improved durability
Enhanced brake comfort thanks to optimized thermal conditions
Curved vane design maintains structural strength while improving noise dampening"

Here is one, for example, that is a direct replacement for the F87 M2 CS:

https://www.fcpeuro.com/products/bmw...r-shw-bfl48251

This is the kind of info I was looking for. Thanks

[NSX2M4]

Klaus Dullinger: M compound brakes have a grey-cast friction ring in a floating arrangement that is connected by pins to the aluminium brake cover. The pin assembly means that as the temperature increases, it is able to expand freely in a radial direction and subsequently cool down again without any residual deformation. This connecting system has been in used since the second generation of the BMW M3.