Concave wheels are all the rage these days, and for good reason because they look just plain awesome on just about everything. Couple some concave spokes with a nice fat-lip, and you’ve got a look destined for aesthetic greatness. However, in order to get that amazing combination of deep concave spokes and a big fat lip you have to be able to fit wheels that are both wide and on the lower end of the offset scale. Why is that? Simple – there has to be enough space to accommodate both.
This is a great visualization of the Big Lip vs. Concave Spokes conundrum. These are both cross sections of 11-inch wide wheels with 6.370 inches of backspacing, sitting on their backs. You can see that to get the concave look, you have to push the spokes into the extra area that would be a nice fat lip on a non-concave wheel.
Forgeline recently posted this short but very informative article to their website that explains how the depth of your wheel’s lip and the depth of concavity are directly correlated. This is one of those situations where it can be tough to have your cake and eat it too. Pushing out the spokes to make them concave is going to eat into the amount of outer lip your wheels have – there’s just no way around it.
It’s also important to understand that it can be tough to produce a concave spoke on a wheel for a car that uses high offsets; because they usually have very little if any lip to begin with. However, for this very reason, Forgeline offers a “shallow” version (with less concavity) of each of their Concave Series wheels to allow fitment on even high offset cars.
Forgeline says, “Obviously, this may not be an issue for vehicles that can accommodate really small backspacing and really wide widths. But for most vehicles, there will be some tradeoff between the concave profile and the outer rim lip depth.”