.. it may be because you are using performance brake pads, which are awesome!
Don't get me wrong, stock OEM brake pads are dusty, but they get worse when your brakes have better grip.
The main culprit of dusty brakes are the discs a.k.a. rotor materials being made of iron, as well as the composite material of brake pads that are a mix of metal with graphite or some other sort of materials. So when they grind on each other, these very fine particles become loose and stick on the surrounding areas. Here is a sample of what Dixcel shows on their website about the dust amount comparison.
A Dixcel type M is a street grade brake pad with effective temperature up to 500℃ whereas Dixcel type Z is a performance circuit brake pad with effective temperature up to 850℃. But this is what the website says. Let's take a look at the real life comparison in Malaysia on a 2018 Subaru Forester using a Dixcel type Z just after 500km of usage, where the left is before and the right is after.
Even the brake callipers are given no mercy from the dust.
So, what do dusty rims mean?
It makes your car look dirty. Usually the front wheels will look darker than the rear.
Long term effects may include fading or corrosion of rims, especially with the mix of acid rain and brake dust byproducts. It even becomes harder to clean off if it is left there for a long period of time. The brake dust is so fine that it sits very well into the rims.
How to prevent dust forming and damaging the looks or even the condition of your wheels?
Upgrade to low dust brake pads, which are usually ceramic or non-asbestos organic. But they will put you back at least MYR 450 for a pair.
Wash your car regularly, at least once a week. 👍🏼
Hope this article was informative. Always remember that car care comes from ourselves.