Wheel Came Off at Track Event!

[Ice323]

Originally Posted by R A W L S

Thanks, I don't know the damage and repair bill yet. Mechanically It will almost certainly need a new rotor and wheel. It may also need a new control arm, and who knows what else. Cosmetically it needs a new fender which the wheel broke while breaking free. I'll post more info in a day or two.

well, man, I wish you the best of luck on that repair total. Look on the bright side. At least it didn't come apart on you in the braking zone of the fastest straight.

[mastek]

Are the wheels powdercoated?

[LiM3y]

I check the torque just before I go out when the wheel is at its coolest.

I also bought new lug nuts just for track use this season. $65 well spent for peace of mind if nothing else.

[Richbot]

Check torque before every session. Not optional IMO. I've forced a student to miss half a session when he had a torque wrench sitting next to his car and hadn't checked them. He had torqued them in the morning and run one session. They turned about 1/4 turn before the wrench clicked.

[MaxL]

Thanks for posting - it's a good lesson for many people here. I always thought torquing in the beginning of a day was enough.

[Richbot]

On many cars it probably is enough to just torque them at the beginning of the day, but I don't bother findingout. It's quick, easy, and you shouldn't be jumping out of the car without looking at it again until the next time you strap in anyway so it can only help you catch other problems. I was once as guilty as the next guy but I got wise the first time I had a wheel try to come off on an out lap during a qualifying session

<- Qualifies as an "Experienced" racer now which means "has screwed up a lot"

[R A W L S]

I think I will switch to studs, I don't think I can trust bolts anymore even if they are brand new. And I will religiously check torque before each session now. All things considered, I am lucky. This happened during a fairly slow hairpin at about 50mph. It could have happened on one of the straights (115+mph) or sweeping corners (70-100mph).

Thanks for all the support and suggestions.

[Groundpilot]

But are the studs safer?

[Erhan]

Originally Posted by M3 09 AND135I 11

But are the studs safer?

If anything I'd guess they're less safe. There are 2 things that needs to be screwed with the studs. But I think it is splitting hair. I use studs. Makes the wheel changes very easy. Also they look really nice.

Thanks to this topic though, I will religiously check my wheels before each session now. And I will get new set of whell studs every season.

[R A W L S]

Originally Posted by erhanh

If anything I'd guess they're less safe. There are 2 things that needs to be screwed with the studs. But I think it is splitting hair. I use studs. Makes the wheel changes very easy. Also they look really nice.

Thanks to this topic though, I will religiously check my wheels before each session now. And I will get new set of whell studs every season.

My bolts were only a year old. I track my car twice a month. If you track more than once a month I'd get new bolts quarterly to play it safe.

[chris328i]

It's very unusual for genuine OEM wheel lug bolts to break. They might strip but they should not break as they are of modest hardness to prevent brittleness and provide good toughness.

[mastek]

were the wheels powdercoated??

[R A W L S]

Originally Posted by mastek

were the wheels powdercoated??

No, not powder coated

[mastek]

Originally Posted by R A W L S

No, not powder coated

Painted? Is it a color or finish?

The reason i bring this up is that sometimes the paint/powdercoat will heat up (heat transfer from brakes) and actually melt down at the wheel's back plate (they are not supposed to paint/powdercoat there).
This will cause space between the wheel and the hub and the rotational stresses will crack the bolt heads.

If your wheel is painted black, pink, whatever .... take a pic of the backplate and post.
Ive seen this happen at the track where the wheel came off as a result.

[LiM3y]

Originally Posted by mastek

Painted? Is it a color or finish?

The reason i bring this up is that sometimes the paint/powdercoat will heat up (heat transfer from brakes) and actually melt down at the wheel's back plate (they are not supposed to paint/powdercoat there).
This will cause space between the wheel and the hub and the rotational stresses will crack the bolt heads.

If your wheel is painted black, pink, whatever .... take a pic of the backplate and post.
Ive seen this happen at the track where the wheel came off as a result.

The ARC-8s aren't painted on the back and the lugnut holes are not painted either.

[mastek]

Originally Posted by LiM3y

The ARC-8s aren't painted on the back and the lugnut holes are not painted either.

Did you know that you can have wheels painted or powdercoated after they are made, regardless of manuf, model??

[LiM3y]

Originally Posted by mastek

Did you know that you can have wheels painted or powdercoated after they are made, regardless of manuf, model??

[mastek]

Originally Posted by LiM3y

Awww -- Thank You -- thats 4 me? right?? -- lol

[aus]

Originally Posted by R A W L S

My bolts were only a year old. I track my car twice a month. If you track more than once a month I'd get new bolts quarterly to play it safe.

From what I've read, you'll need to change studs too after a certain time/use.

[sharkfighter]

Originally Posted by mastek

Did you know that you can have wheels painted or powdercoated after they are made, regardless of manuf, model??

Did the OP have his lug holes or backs of the Arc-8 wheels painted?

[R A W L S]

Originally Posted by sharkfighter

Did the OP have his lug holes or backs of the Arc-8 wheels painted?

There is no powder coating or paint anywhere on the wheel or lug holes. Thanks sharkfighter.

[r_seng]

Wow, this is a first for me hearing of something like this happening from BMW. Subbed for more info.