Lifespan of wheels

Does anyone have experience with wheels aging out? I know this is a subjective question based on type of wheel, use, care etc. But we're not talking F1 wheels that are used once.

The wheels in question are 14x7 Borbetts from a 1.8L Miata that sees use in HDPE events and long enduros only. We had 12 wheels, all purchased at about the same time and all used equally since then. In 2007 we found one w/ a cracked spoke so we scrapped it and looked at the remaining 11, they all looked fine. I was dismounting tires off of them this week and found that 5 of them have what look like hairline cracks on the backside of at least one spoke.

Has anyone had wheel failures that were not directly related to contact w/ something more than a track curb? Anyone ever felt their wheels were simply too old to be reliable?

They are consumables, but to what extent is hard to pin down. I've thankfully never had issues with them cracking on it cars but plenty of experience with them failing on grand-am gt cars. But even then it was hit or miss, the mazda and porsche cars I worked on never seemed to have issues other than drivers bending them hitting things, the gto.r that always ended up next to us were still using former trg sets and they were failing left and right. But this was a team trying to get every last bit of use out of old parts that had some issues even when new.

Also make sure it's not just a crack in the powder coating. I had some wheels that the powder coating cracked because of the heat from the brakes/hubs, but the wheel itself was fine.

Check out this thread: http://forums.bimmerforums.com/forum...corvette+wheel

I see a yellow C-6 around town with these same wheels. Crazy to think they don't last so long with R-comps on them.

Well with a little more investigating I've learned some things.

Took one and wire brushed the paint off, got down to bare metal. Dye penetrant test was in conclusive until I took a rubber mallet & whacked the spoke in question. Dye penetrant then shows a small crack. Of course this does not indicate if it is a surface crack or goes deeper. No crack wraps around from back towards front more than 3/32".

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Originally Posted by Z3_GoCar

Check out this thread: http://forums.bimmerforums.com/forum...corvette+wheel

I see a yellow C-6 around town with these same wheels. Crazy to think they don't last so long with R-comps on them.

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I have seen those pics before. From what I have heard that was a copy/fake wheel notg a factory piece. Supposedly there have been many that have seen this same failure.

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Originally Posted by cjb25hs

I have seen those pics before. From what I have heard that was a copy/fake wheel notg a factory piece. Supposedly there have been many that have seen this same failure.

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That's a good point, I hadn't thought that it was an oem reproduction. I'll ask the op if there's any more details.

I have actually had a wheel failure at speed. But in the 30+ years I've been racing I've only seen wheel failures like the one in the picture about a half dozen times. I've seen as many stub axle failures on the rear of Z-cars and 2002s as wheel failures on everything else. For me, it happens so rarely, it's not something that would cause me to scrap a wheel based solely on age. However, you should regularly clean and eyeball your wheels, particularly at the inside base of the spokes and where the spokes meet the centers because usually these are the points of highest stress. If you see what looks like cracks then have them tested with the dye penetrant and discard them if they are indeed cracked (if they're expensive) or just replace them (if they're cheap.)

My experience was a left rear breaking out the center on my ITB Capri. Going through Turn 6 at Road Atlanta I felt a big thump and thought the following car had nailed me. But then I saw a wheel (mine!!) bounding 50 feet in the air, over the Turn 7 guardrail and down the hill. No real damage to the car, but it sure took a long time to find the remains of the wheel - about 200 feet down the hill. We checked the remainder of the set (they were ancient Ansen Sprint Mags - tells you how long ago this was) and found two others were cracked, so we retired the whole set. I became much more religious about inspecting wheels after that, but I've never seen any recurrence.

We have had failures with several brands of wheels on our ITA/SM Miatas; 50 hours seems to be the magic number for one particular brand. The other brand we have seen failures on lasted about the equivalnet for 4 years (2 drivers, ful seasons and 2 years in 'real time')

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Originally Posted by Marcus Miller

We have had failures with several brands of wheels on our ITA/SM Miatas; 50 hours seems to be the magic number for one particular brand. The other brand we have seen failures on lasted about the equivalnet for 4 years (2 drivers, ful seasons and 2 years in 'real time')

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I bet I'm not the only one who would be very interested in knowing what brands / models you have data on failing in 50 hours. care to expand upon that?

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Originally Posted by Chip42

I bet I'm not the only one who would be very interested in knowing what brands / models you have data on failing in 50 hours. care to expand upon that?

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Most common failures have been Rotas, specifically the RB (panasport lookalike)
We are at 5 sets and counting, max life was about 80 hours, minimum was 40, with the other three falling right at about 50 hours.
All cracked through the lug holes. I can vouch for at least 4 of the 5 sets that none had been run while improperly torqued (tight, or loose).

All were run on Miatas, in SM spec, or light IT spec (Koni's/ Springs),with Kumhos or Toyo's on them. They were run in a mix of sprints and enduros, with the majority of thier life coming on Kumhos in enduros.

The other brand we had issues with was Team Dynamics, two of the 1.2 model. Same failure, but these had Toyos mounted their entire life, and had only been run in sprints, with maybe one enduro on them.

All of the BMW 2002 rear stub axle failures that I've seen have been when the rear suspension bushings were delrin. Never seen a failure with the stock rubber bushings.
Regards,
Chuck