For starters, all BRINK Wheels are dual-drilled. This was not part of our initial plan; however, after consulting with several industry engineers, we decided to go this route.
Below, we’ll share what we learned when making this decision.
The biggest misconception we hear is that dual-drilled wheels are not safe. That misconception is based mostly on the wheel being weaker due to its having more holes on the mounting pad. In the image below, you can see our finite element analysis (FEA) report, which displays, on the left, a chart representing the stress levels of the wheel when tested. This report predicts how a product will react to real-world forces, vibration, heat, and other physical effects. Finite element analysis shows whether a product will break, wear out, or work the way it was designed.
The lower the stress level, the stronger that portion of the wheel is. If you analyze the report below, you’ll notice that the mounting pad of the wheel where the dual drilled holes are located is dark blue, indicating a low stress score. According to the engineers we consulted with (outside of our factory engineers), it is very rare for the mounting pad of a wheel to have any stress, as typically the stress is found mid-spoke (as in the case of our wheel).
One of the engineers we consulted with noted that, some time back, he had worked on a project with some reputable brands. The project involved drilling several holes around the center lock portion of a Formula 1 wheel in an effort to reduce weight. When they tested the wheel, they found no compromise in its strength and were able to shave off some weight. So, in actuality, there is an advantage to dual-drilled wheels from a weight savings standpoint.
With that said, the mounting pad of a dual-drilled wheel is the area that should be of the least concern for those worried about the strength of a wheel.
It is also important to note that some manufacturers do combine other bolt patterns, which decreases the distance between those holes. This is an entirely different scenario.
We will always dual-drill in the most ethical manner and review computerized FEA reports before going into production to ensure that the base stress levels are not exceeded in any way.
So, why not just make your wheels single-drilled?
After consulting with several industry veterans and educating ourselves on the topic, we have determined that the better question is “Why would we?” The wheels are just as strong as single-drilled wheels and pose no danger to our customers.
In addition, manufacturing our wheels as dual-drilled allowed us to save 50% on the shelf and warehouse space we initially intended. We took these savings and invested them into making a better product by going flow-formed. This, on average, is 30% stronger and 26% lighter than a comparable cast wheel.
We also passed a portion of the savings down to our customers, as we can offer flow-formed wheels for cast wheel prices.
Additional samples of dual-drilled race wheels
BBS Motorsport Division race wheels (18 holes on the mounting pad)
The below Work RS race wheels go as far as drilling holes between the lug holes, which are not even lug holes. This means they found it beneficial from a weight savings standpoint to create those additional holes.
We hope this post serves as an informative resource for those considering dual-drilled wheels (even if they aren’t our wheels). The bottom line is that when done ethically dual-drilled does not compromise the wheel’s strength. Further proof of this, aside from our FEA reports, is that dual-drilled wheels have been adopted within race circuits, where they did it for the weight savings advantage.