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Processes and Features - Expertise - BBS USA


Every technology has a limit.  Cast aluminum wheels were a big improvement over steel wheels, however when it comes to performance, there are other technologies like flow-forming or forging that surpass a standard cast wheel.  These higher level technologies will allow a reduction in weight (while maintaining the stiffness and durability) that will improve vehicle performance.   

Flow-forming has been an important production technology at BBS for the past 20 years.  Although many other wheel companies talk about “Flow-forming” as if it is something new, we introduced our first aftermarket flow-formed wheel back in 1996.

Current BBS aftermarket designs that benefit from the "Flow Forming" process are CI-R CH, CH-R, and CHRII.  BBS supplies cast flow-formed wheels for many high performance OEM manufacturers including: BMW, Audi, Mercedes and Porsche.  Also, some factory racing programs from BMW, Ferrari and Ford have selected a BBS cast flow-formed product specifically for track use.  

Explanation :  "Flow Forming" is a procedure that uses 3 hydraulic rollers and tremendous pressure to ”Form” the inner rim area.  Through this process, the hydraulic rollers force the cast material to conform to the profile of the massive steel tooling.  During the process, the full width of the rim is created.

BBS Flow-Forming Stages

Benefit:  The pressure used in this process actually changes the mechanical properties and the grain structure of the cast rim area to have strength, stiffness and impact values closer to that of a forged rim.  "Flow Forming" also helps reduce the weight up to 15% when compared to a standard cast wheel.  The overall “Stiffness to Weight Ratio” is very good and can deliver a high level of performance at a cost that is much lower than a forged wheel.  

Material x-section (grain structure) comparison of “Standard” to “Flow-Formed” areas

Stainless steel rim protector

With our patented rim protector made of polished stainless steel, you can permanently safeguard the high-quality look of your wheels. Should damage occur, the rim protector is available as a replaceable spare part and can be exchanged easily without having to replace the entire rim or remove the tire.

Back-milled spokes

Milling the spokes allows BBS to hit just the right balance between wheel weight and stability. Using a special multi-axis CNC milling process, the area of the spokes that do not contribute to its stability can be removed.  Before destructive testing is done in our test facility, a computer simulation of the wheel type is subjected to several test cycles using different spoke configurations to already ensure the correct balance is achieved during the construction phase.  This technology was first used on our Formula 1 wheels and now we use this special machining operation to improve the performance of many road wheels like the LM-R, CI-R, CH-R, CHRII, CX-R and the ultra-exclusive forged aluminum FI and FI-R wheels.