Circle Wheel failure
 

http://www.circlewheelsfail.com/

pic Yikes!!! :eek:

http://www.sccaforums.com/ubb/ultima...p/topic/2/1499

I hope I never have to experience anything as puckerific as that...

Is it Circle or Diamonds that bend easily when you hit a curb? I never can keep the two of them straight.

Why does Circle make wheels with diamond shape cutouts and Diamond Wheels make circle cutouts?

It's racing, stuff fails. The first gen brake rotors are failing like crazy in EP racing. If I had a set of circle racing wheels I would inspect them but certainly not panic. Many, many racers are using this wheel. Thanks for the heads up.;)

Those also look like they were powder coated, (- wait can you even powder coat aluminum???) that process has been known to contribute to wheel failure in 5 liter mustangs...

MM

edit: spelling

I saw a 15x10 circle steel wheel fail at my local Ax on a B MOD car. The wheel was seven years old. This is an aluminum wheel, and is a different animal. The guy never answers any questions about how old the wheels are, but most cars that run the steel wheels replace them regularly from what I have gathered talking to guys that run them. I run Real Racing wheels, 3 piece, light, and less than 300.00 (16x12s)a corner. Anyone see a three piece come apart ever, or even hear of one? I have seen them loose air quite quickly, but nothing catastrophic like the stopck FD wheel, or the Circle wheel.

It depends on the shop.... ;)

Powder Coating
 

You can powder coat anything that will conduct electricity.

A friend of mine had an OEM BMW wheel separate the same way while on a road course. It was an E30, and has been autocrossed and tracked a fair bit. He and his car fortunately escaped serious harm.

Metal fatigue is part of motorsport. That's why the pros magnaflux stuff.

Good point. In the scca forum thread link, somebody mentioned that pros also replace wheels every year - and that some still fail. Another guy mentioned a case where someone purchased an auto-x champion's car and had a wheel fail - it had obviously been driven very hard.

Still you think Circle could've worked with the guy a bit - there are plenty of diplomatic ways to not admit fault without causing someone to start speading bad word-of-mouth.

I think the X ray inspection of the wheel wheel that did not fail and the letter from the inspector is fairly damning. From the letter: "Examination of the x ray film reveals a line of incomplete fusion and porosity equal to approximately seventy-five percent (75%) of the length of the welded area." That's a pretty shitty weld. I'm also curious to know how old the failed wheel was. In any case spun aluminum wheels probably aren't the best thing for road racing. Weld doesn't want their spun wheels used in any racing other than drags.

You can't magnaflux a non magnetic wheel, BTW.

How did the powder coating contribute to the wheel failure? Did the coating inhibit inspecting for cracks? Did the heating of the wheel to melt the powder anneal the previous heat treating? Inquiring minds want to know.