Rims cracking?
 

Hey guys so heres the setup on my car.

H&R springs, KYB rear struts, 25mm spacers, OE wheels powder coated black chrome, 245/40/18 Hankook RS-3s.

First time my rear rims cracked the car had runflats and blown out Koni's (which i later got warrantied), and sprint springs. So i figured okay - the rear tires were just getting too much shock over bumps.

Now I'm prettty sure these KYBs aren't holding up for how low I am and my rims cracked again, its only the rear rims that crack.
Just wondering if anyone else has experienced this? I love how the stockers look powerdercoated but I wonder if its the baking process thats weakening them?

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Phew, good thing I paid attention in my engineering material science class. :rofl:

The factory wheels are cast wheels that should be 356-T6 alloy. Normally powder coating requires a controlled baking temp of around 400*f for about 15-30 minutes, which isn't sufficient enough to cause significant annealing or molecular structure change of cast alloys. With that said, it MAY be safe to rule out the cause of the cracking to be the powder coating. I say "may", because I have no idea who PC'd your wheels and if it was in a controlled environment at the ideal temp and timing.

Forged wheels on the other hand. Avoid powder coating those...


Edit: btw it's wheels, not rims.

Damn that's nuts!

Is this common? First I time I see this on a s1.

Its common if the baking process is not done right. Ive seen a guy with enkei RPF1 and his spokes cracked a year after he had them powder coated.

Thanks for the educated reply!

I've cracked a total of 5 wheels now. Just saw a hairline fracture in the front one.
I'm sick of spending the money to get them powdercoated so I'm picking up some Rota P45Rs tonight hopefully!

I'm thinking maybe the spacers put too much load on the wheels? I've heard they increase load on the wheel bearings - I wonder if the same energy is transferred to the wheel - especially during braking cause thats when I noticed it the first couple times, and yesterday.

Weird, I have never seen this before so it has to be the powder coating process. However, there are knock offs of the factory wheels believe it or not so if you are buying new replacements online it is possible they are the Chinese knock off versions. There is a thread about those somewhere.

Ive seen this once before. It was on a set of stock RSX typeS wheels that a kid I know had gotten powder-coated white. He had the car since it was new. I think it was an 05?. He lowered the car last year and had the wheels powder-coated. Within 6 months a couple spokes cracked on both fronts. Weird coincidence?

That is dangerous to drive with it. If mine is like that, I would change it.

Can you do a little research on the baking process of the wheels when they were done? I question that because there are cases where some would bake metals up to nearly 1000*f for powder coating. Clearly that is beyond the safe spectrum of cast wheels.

I did change them out right away, now I've got Rota P45Rs and I love em! :p:

I'm thinking it was a combination of things including the wheels not being properly baked. The guy is ALWAYS busy and does a lot of commercial stuff. With that being said I'm sure they crank it up a few degrees to speed up the process.

Read the thread, he already replaced the wheels with new ones.

Edit: Wait, is that spam? Why yes, yes it is. Reported.

But this seems not rim cracking it just seems that the nickle on the rim is disturb that's why it seems like it is going toward the breaking of the rim. Anyway :D

Um, what?

The rim cracked. I had a total of 5 rims do the EXACT same crack. I had my brother drive the car slowly and I could physically see the spoke popping back and forth.
There is no nickel in the rim, it's powdercoat.