Markus

When I bought my Miata, it already had the bling bling white stripes painted on it. So I had some OEM rims powdercoated white for my track rubber:




The white look is kind of fun but a b!tch to keep clean. So after my last track day at Beaverun, I washed the wheels and found this on one of my wheels:




Kind of hard to see I know, but it's a little hairline stress fracture. Not even that visible. I pulled the offending rim and wiped some of the grime off the back only to find worse:




The rim is 7 spoke and it has stress cracks on at least 4 of them. So yeah I don't think I'll be using that again any time soon. Anyone got a spare Miata rim laying around?

About bling bling saving the day - I really don't know if I would have noticed the small front crack if the rim was still OEM or dark finish. The white certainly helped it stand out.

As far as cause, I had an overheating problem with my car so I drove it to work and back a couple of times. I did crank a pothole along some train tracks kind of hard, I'm thinking that combined with the lowered suspension, stiff springs and stiff sidewall of the tire were enough to do it.

I thought I'd put this out there just so everyone can add yet one more thing to the list of before/after track prep = check rimz yo!

- Markus

FrostySol

wow, it's a good thing you caught that before it became a real problem. Anyone else have this happen to them? Kinda scary when you think about what could happen there

Mike_C

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FrostySol &raquo;</TD></TR><TR><TD CLASS="quote">wow, it's a good thing you caught that before it became a real problem. Anyone else have this happen to them? Kinda scary when you think about what could happen there </TD></TR></TABLE>



Wheel breaks, car slides off track, body of car digs in to ground, flippage... Not a pretty picture.

EtherGhost

Is this a reason why real some race cars use white wheels, to be able to see these cracks?

Andrew240z

Anyone see my car at an event? #81 H4 the wheels are always clean at the beginning of a weekend. I pull all four wheels off after every event and clean them and check them. I also try to do a nut and bolt after every weekend. Granted it is a race car but never hurts to check. Proper race prep is everything. Now trying to get faster is the tough thing.

#81 H4 Hankook Tires

577HondaPrelude

I bet it was the stress from extremely high winds created by a red prelude passing you on the front strait. ...or maybe a pot hole.

Track rat

Nice find!

I learned the hard way after breaking a wheel in T#3 at Road Atlanta that wheels need frequent inspections.

Wheels a wearable parts!

Driven

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EtherGhost &raquo;</TD></TR><TR><TD CLASS="quote">Is this a reason why real some race cars use white wheels, to be able to see these cracks?</TD></TR></TABLE>
bling, easier to find problems, etc.

A lot of racers paint their engine bays white to also locate problems (oil leaks, lost bolts, etc).

only the street racing crowd paints their engine bays black for some unknown reason

Tyson

have you ruled out that the hairlines may be cracks in just the coating? just a thought.

Outsane

noticed that alot of the btcc cars have silver fender wells...too

krshultz

Yeah, I've got a set of Enkeis that I painted BBQ Grill black that I think I'm going to retire from competitive use and put on the CRX. They've got a lot of hard miles on them and are pretty trashed.

Glad you found it doing a visual instead of a lap.

tjbizzo

I've heard about that on some miata forums before. It seems that they made at least three versions of this wheel: the hollow spoke, the semi-hollow spoke, and the solid spoke. Yours is a hollow spoke and weighs the least at 10.8 lb. Although slightly heavier at 11.2 and 11.5 lb. the semi-hollow spoke and solid spoke versions are much more robust. Read about them here . Better yet, look right above yours at the '93 OEM BBS alloys. mmmmm......8.5 lb. sweeeet!

civicrr

Like above, I take the wheels off & clean them after every weekend. It is a PITA but worth the effort. I started doing it after reading an article in GRM. I can't remember the company, but they did as part of their arrive & drive program. Anyway, that is how they found out that their wheels were starting to get stress cracks.

mattjohnston

The majority of factory rally cars are painted white inside for a reason

SuzukaBlueAP2

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Driven &raquo;</TD></TR><TR><TD CLASS="quote">

only the street racing crowd paints their engine bays black for some unknown reason</TD></TR></TABLE>

To hide the half-assed work under the hood

Tad

yeh, 3rd gen rx7 rims did that too,
or at least a certain batch of them did.

mazda ended up adding some extra material around the base of each spoke to fix the prob.

Markus

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 577HondaPrelude &raquo;</TD></TR><TR><TD CLASS="quote">I bet it was the stress from extremely high winds created by a red prelude passing you on the front strait. ...or maybe a pot hole.</TD></TR></TABLE>

ARRRGHHH. Nothing like a smart-@ssed Prelude driver I tell ya! Does that mean I can send the replacement bill down to WVA?


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">have you ruled out that the hairlines may be cracks in just the coating? just a thought.</TD></TR></TABLE>

That's what I thought at first. I know it's kind of hard to tell with the pictures but when I pulled the rim off it's evident that the cracks are the whole way through the spokes.

Like I said, I think I know when it happened. Which was BEFORE driving an hour on the freeway to the track, doing 6 or 7 sessions over two days, getting my @ss whooped by a certain red Prelude, and driving an hour home. Guess I done got lucky. Or maybe that little guardian angel pin my momma made me put in the car was really working!

- Markus

metalworker

I've always had a different philosopy of not powder coating stuff so that I could find the cracks. I understand the idea of white paint, but I'm not sure that powder coating wouldn't hide a crack more often than show it. You will never see coatings on most purpose built race car suspension pieces (formula, sports racer, drag ) and wing mounts for this reason.
Wheels definitely have a life span in racing conditions. If you have found cracks in one, I'll bet another willl be right behind it.

Markus

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by metalworker &raquo;</TD></TR><TR><TD CLASS="quote">I've always had a different philosopy of not powder coating stuff so that I could find the cracks. I understand the idea of white paint, but I'm not sure that powder coating wouldn't hide a crack more often than show it. </TD></TR></TABLE>

Interesting. I guess it might depend on the type and finish of the material? The main thing is to clean and inspect at least once and awhile.

kb58

Maybe, but I know powder-coat tends to chip, which means it's brittle, which means it's very unlikely to hide a crack by "bridging" it.

Vanilla Ic3

Back when US and UK twins were 'motocross' bikes, some race bikes would sport white frames to make cracks easy to spot... I could see how a thick coating of paint could hide small cracks. A thin layer of paint should show them well.

Safir

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mattjohnston &raquo;</TD></TR><TR><TD CLASS="quote">The majority of factory rally cars are painted white inside for a reason </TD></TR></TABLE>

many rally cars are white because sponsor decals show up better on white, even when teh car is crashed up or dirty

CALM_AS_A_BOMB

hmm perhaps a little JB weld ? j/k go to http://www.miata.net you can find some miata replacements at a good price. or ebay

Bbasso

Good catch, better now then later.

sporkcrx

Holy ****, that must of scared the bejesus out of you when you found all of those cracks.