Corksport Lightweight Lug Nut Failure

[pzr2874]

So CS threw up an additional disclaimer in the midst of all this? @Joel@CorkSport;

CP-e did that shit back in the day when you had to send in a FP in as core. Many didn't get the core because they added the disclaimer "must be a working FP".

[Crarrs]

Originally Posted by Deldran I saw all this carnage. Nice write up gringo. I was glad to see you out the next day. Did you get into MSM hopefully the fender isn't to much from them to get replaced Sent from my XT1080 using Tapatalk 4

Originally Posted by Gringo East Its on my list of things to do. From what I'm seeing online the fenders are at most a couple hundred. The real expense will be the paint.

MSM discount for autocrossers doesn't extend to bodywork, only chassis/engine parts. Check the terms.

[dubtastic]

WOW! Kudos to you for going back out and racing again that is some spirit right there! Glad you are safe!

[pwdunmore]

Originally Posted by Joel@CorkSport I have talked to the OP and hopefully sorted things out. I'll do my best to answer most of the questions I've seen in the last few minutes here. Based on my measurements: Stock Wheel thickness (at the hub face): 11.4mm Stock Wheel Stud thickness ( from rotor face) 24.0mm Stock Wheel Stud Diameter: 11.8mm Typically, you want a 1 to 1 ratio for the stud diameter to thread engagement. In this case, that would be 11.8mm Based on the math, that leaves you approx 0.8mm of wiggle room on a stock wheel with stock lugnuts. The OP had a wheel approx 1.5mm thicker than the OE giving him approx 11.1mm of thread engagement which is below spec but probably plenty safe (as it has been for the literally hundreds of other customers running our lugnuts). When you add in the 5mm wheel spacer you are now left with only 6.1mm of thread engagement for the lugnuts. The factory wheel studs are a 1.5mm thread pitch so you would then be left with just 4.0666 threads on which to keep your wheels on. With a steel lugnut and a factory wheel, Mazda would not consider that safe and neither would I. However, I am very interested to hear what anyone else thinks as I want to be as fair as possible and certainly want to treat people the way I would wish to be treated so please, let me know your thoughts. Cheers, Joel

Based on my math that has nothing to do with steel vs aluminum with thermal expansion.

And the nominal difference the number of threads grabbing has nothing to do with the amount of active friction holding the wheel there...

If gringo was shearing off the wheels studs that would have been the problem but the stud is still there... it was stripped from the lug nut not grabbing it properly on the stud.

Does that make sense?

[SofaKingAwesome]

Cached links (Respective dates at very top of page):

CORKSPORT Lightweight Lug Nut Set

Wasn't there...

And an older one: http://web.archive.org/web/201205250...g-nut-set.html

[p057]

Originally Posted by shpeedtree Hopefully they won't have to recall all these nuts, and people will realize the risk of using spacers, I have seen posts on stance forums that say you're safe with four turns on the lug nuts.

stance retards sit in parking lots, they don't do anything near as aggressive as Auto-X or even taking a turn faster than a city bus.

[WetzMS3]

I was planing on ordering these, until I heard Matt and Dan find out about this on Monday.

Good luck getting it sorted out.

[Mr Wilson]

Looks somewhat close...

From Sept last year.....sorry for the huge pic. CS did take care of me without any fuss.

[pwdunmore]

and it begins

[ricknm]

@rfinkle2; @Voltron Locos;




let the fun begin

[MonstaSpeed6]

Did Cullen take over at CorkSport? In for Joel Eats Penises vinyl.

[Deldran]

Originally Posted by Mr Wilson Looks somewhat close... From Sept last year.....sorry for the huge pic. CS did take care of me without any fuss.

cannot see pic

[Haltech]

I am one of those against the use of wheel spacers on race tracks. Granted, i would be using a steel lug myself, however... even with extended studs from ARP, i still would never track a car on spacers, just my personal preference.

What your video shows is nothing compared to the results of a high speed track run resulting in a wheel failure. you are VERY lucky you did not get hurt, but more importantly, hurt anyone else as tracks dont cover damages nor does your insurance unless you have special track insurance.

Its unfortunate this happened to your car and i hope CS takes care of you. I would advise CS to be very adamant about the use of their lugs used on spacers. Its kind of hard to really point the blame at CS since these were used on spacers. Im just happy to see no one hurt regardless.

[breakfstincluded]

Well you see this is why we all need TWM Titanium lug nuts, they're only 500$.

[usgiorgi]

Originally Posted by breakfstincluded Well you see this is why we all need TWM Titanium lug nuts, they're only 500$.

I thought you were joking... but then I googled it... $560 for a set of titanium lug nuts. DAMN!

[breakfstincluded]

I don't blame you, I think we might see them in a Neiman Marcus catalog this year lol

[Mr Wilson]

Originally Posted by Deldran cannot see pic

I'll re-host when I get home. Work blocks most photo sharing sites.

[CWP_MS3]

Originally Posted by breakfstincluded Well you see this is why we all need TWM Titanium lug nuts, they're only 500$.

You ever heard of the dollar store, where everything is a $1? Welcome to the 500 dollar store... Everything from TMW is $500.... -__-

Fuck a $200 shift knob. Shit better fucking shift itself into gear.

[Voltron]

This happened to me at track., 10 of the 20 lugs broke coming off.
I was stuck with my slicks on, we had to drop the car, and rock the car until the remainder of the lugs somewhat got loose and then use needle nose pliers to twist them off.


Never been a fan of this company.
Will never recommend anyone I know to buy their shit either.

Oh yeah, my car fell off the jack after we rocked it, my side skirt and fender are fucked.

I would be really pissed had that shit broke off while banging down the track.

[Haltech]

Originally Posted by Voltron Locos This happened to me at track., 10 of the 20 lugs broke coming off. I was stuck with my slicks on, we had to drop the car, and rock the car until the remainder of the lugs somewhat got loose and then use needle nose pliers to twist them off. Never been a fan of this company. Will never recommend anyone I know to buy their shit either. Oh yeah, my car fell off the jack after we rocked it, my side skirt and fender are fucked. I would be really passed had that shit broke off while banging down the track.

Were you running spacers on those slicks teddy or OEM?

[England15j]

This is exactly what mine looked like when they failed. I don't use spacers or track my car. They just shattered as I was torquing them down.

[usgiorgi]

Holy shit if I had these on my car right now, I'd run outside and swap stocks back on...

[JgamB]

@nindoja; hasn't chimed in yet, but we went to the drag strip and had two of these back off to finger tight and he was only alerted by the rumbling noise. When we replaced his brake pads a week later, I took his wheels off and again 3 of them were extremely loose, and fewer than half of the lugs *felt* like 65ft/lb breaking loose.

They were not threading cleanly going back on - enough so that I made a comment about the threads feeling sloppy and the lugs wobbling further down the stud than I cared to see.

He recently sheared one in the same spot as the OP's pics, but I wasn't there for that and I'm not aware of the circumstances involved. If you're sporting these, spacers or not, I'd triple check the torque. I love Corksport but these aren't going on my car.

[rfinkle2]

I have to admit, I'm a little frustrated with Corksport as well.

The lugs that Teddy ran @ the track that caused a problem were Corksport's second revision of these lugs. He borrowed them from me. I didn't make a stink over it because I'm just glad Teddy is OK, but I'm out a set of lugs...

My friend Ricknm above and I work on his car in my garage quite a bit and he really likes to use Corksport parts.

There have been numerous (3 times iirc) occasions that we've had to fudge installs, or use parts that I had handy to complete his installs correctly, because things just didn't line up straight or this or that was not correct.

Also, I know of numerous e-mails that Corksport was sent with no answer (not from me).

Anyhow, I'm just bothered by the idea that the lug nuts are breaking on a guys car whom I lent them to, that another of my friend's e-mails go unanswered, and a lot of little promises and some install hours were wasted in between.

I don't have any of Corksport's parts, well 1, an underhood led strip, and really have a hard time recommending them when people ask what brand parts to buy.

I also am out a set of lugs, am sitting on a v1 catch can with a glued on lid and just overall a little frustrated with them @ this point.

[AMOC]

This is why I will never run "lightweight" lug nuts.

Cork sport isn't really the only company to blame, the entire concept is to blame.

Lightweight lugs do absolutely nothing for your car except lighten up about 5 actual pounds at highway speeds, if that much. Take a poo if you want that weight gone.

All lightweight / aluminum lugs are known for doing this because.. Well they're aluminum.

Never have and never will run aluminum lugs for this very reason, defend them all you want, but gains are nil. All you get out of them are lighter wallets each time you warp or break one.

[hnda etr]

One thing to keep in mind, is that the JBR spacer is not hub-centric to the wheel. It is hub centric, meaning that is is centered to the bore on the hub, however it is not centered to the wheel hub bore. It is relying on the 2-3mm lip (from what i'm guess from the pic) sticking out from the spacer to center the wheel. If the wheel doesn't sit on the lip of the hub bore perfectly, your lug nuts may have additional forces being applied to them because you are now in essence running a lug centric (i think that's what it's called) setup - relying on the lug nuts to center the wheel on the hub.

FYI - I got a vendor thread shut down on M247 for selling these types of spacers - but he was selling them thicker than 5mm also. The thread was deleted on M247, but here's the thread on MSF I started about it: http://www.mazdaspeedforums.org/foru...47-fail-68083/

Also, I emailed JBR about his design suggesting a change (no response). I'm not pointing a finger at JBR at all - he has great stuff, but just posting additional information to give you all things to consider.

EDIT 2: Here is an example of Hub AND Wheel centric spacers: http://www.motorsport-tech.com/wheel_spacers.html

[Voltron]

Originally Posted by Haltech Were yo running spacers on those slicks teddy or OEM?

The fronts had spacers but Are bolted up to oem studs and the cs lugs bolt up to the spacer studs. The rears I used no spacers so this fail has nothing to do with it kevin

[CorkSport]

Originally Posted by SofaKingAwesome Cached links (Respective dates at very top of page): CORKSPORT Lightweight Lug Nut Set Wasn't there... And an older one: CORKSPORT Lightweight Lug Nut Set

I don't understand this... I added this warning the minute after I got off the phone with the OP. I wouldn't want anyone else to put ANY lugnuts on with only 4 threads. I get the feeling that if I didn't do it I would still get some people complaining that we "still didn't have a warning on the site about it".

Do you want pro-active or do you want nothing???

I don't want this to happen again, I don't want this to happen to anyone, ever, period. I'm very upset that this happened in the first place and want to make sure it doesn't happen again. This is a pretty big snowball of issues and we happen to be one of parts involved. I don't see any warnings from the wheel manufacturer or the spacer manufacturer. I've also already done more research in the last few hours than easily anyone else has or has posted. This is a big deal to me and I made sure to contact the OP personally and make additions to the website to make sure we can hopefully prevent this from happening again.

Cheers,
Joel

[Voltron]

Originally Posted by AMOC This is why I will never run "lightweight" lug nuts. Cork sport isn't really the only company to blame, the entire concept is to blame. Lightweight lugs do absolutely nothing for your car except lighten up about 5 actual pounds at highway speeds, if that much. Take a poo if you want that weight gone. All lightweight / aluminum lugs are known for doing this because.. Well they're aluminum. Never have and never will run aluminum lugs for this very reason, defend them all you want, but gains are nil. All you get out of them are lighter wallets each time you warp or break one.

I ran project my lugs for almost a year with no issues including on my old slicks.

[pwdunmore]

Originally Posted by Joel@CorkSport I don't understand this... I added this warning the minute after I got off the phone with the OP. I wouldn't want anyone else to put ANY lugnuts on with only 4 threads. I get the feeling that if I didn't do it I would still get some people complaining that we "still didn't have a warning on the site about it". Do you want pro-active or do you want nothing??? I don't want this to happen again, I don't want this to happen to anyone, ever, period. I'm very upset that this happened in the first place and want to make sure it doesn't happen again. This is a pretty big snowball of issues and we happen to be one of parts involved. I don't see any warnings from the wheel manufacturer or the spacer manufacturer. I've also already done more research in the last few hours than easily anyone else has or has posted. This is a big deal to me and I made sure to contact the OP personally and make additions to the website to make sure we can hopefully prevent this from happening again. Cheers, Joel

I don't think the threading is the main issue also, yes there should be the specified number of turns but there seems to be an issue with the lug nuts themselves not wanting to hold onto the studs after being warmed up.

The front wheels get considerably hotter than the rears. The two thermal expansions of the lugs and studs are different so when the lugs expand the steel hasn't as much. Just my take on it though. Good luck with finding the solution, I don't think it will take too long just a little tinkering with new materials.

ps good on you for being proactive but you should add the date it was revised

[JgamB]

@Joel@CorkSport; is there any chance there was a machining discrepancy with a recent batch of product? The lugs Nindoja had exhibited a lot more play in the threads than the stockers. I expressed my concern about putting them back on the car from that feeling alone.

I guess there's always a chance that his studs were stretched from countless tire swaps, might've been hit with an impact at a service station, etc. I'll just stop conjecturing and let you guys work this out. My CS TMIC gets here on the 9th, very much looking forward to that install.

[usgiorgi]

I think the reason people were upset at the recent warning on the site is because it could have been a ploy to say "we warned you". We just wanted to make sure to say that all precautions that were provided by corksport (at the time of purchase) were followed by the OP.

[CorkSport]

Originally Posted by JgamB @Joel@CorkSport; is there any chance there was a machining discrepancy with a recent batch of product? The lugs Nindoja had exhibited a lot more play in the threads than the stockers. I expressed my concern about putting them back on the car from that feeling alone.

Great question. We have literally sold hundreds of sets and the only problem we've seen in any reproducible number is the damage from using an impact gun on them (That's why we have that warning on the product page). If you have a possible issue that you are concerned about, PLEASE, send those back to me (address it to Joel Tandberg at CorkSport) and I will personally work with engineering and QA to make sure they are fine and within specs. If not, I will send you new ones or refund your money. No question.

Cheers,
Joel

[MS3johanna]

I was on site at the event as well. It looked pretty brutal, but I'm glad you were unharmed and your car didn't receive more damage than it did. I was quite surprised to see you out there on Monday as well- that was awesome!

Corksport really should have had the disclaimer/warning on their product specs before- it's too bad a few good speed3's had to go down to get it there. They are the engineers. I don't think they can assume an average consumer will take each 0.1mm into consideration when designing their wheel setups. Hopefully the new warning helps others avoid this failure in the future. I do think the respectable thing to do would be to compensate those individuals that were subject to the failure before the warning was posted.

Although really, I don't think I'm convinced that your lugnuts are the right place for weight savings...



Sidenote:

Originally Posted by Crarrs MSM discount for autocrossers doesn't extend to bodywork, only chassis/engine parts. Check the terms.

You can order anything on their website. I ordered an LED taillight and a washer blade from them with my discount, over the phone. Didn't question it.

[SofaKingAwesome]

Originally Posted by Joel@CorkSport I don't understand this... I added this warning the minute after I got off the phone with the OP. I wouldn't want anyone else to put ANY lugnuts on with only 4 threads. I get the feeling that if I didn't do it I would still get some people complaining that we "still didn't have a warning on the site about it". Do you want pro-active or do you want nothing??? I don't want this to happen again, I don't want this to happen to anyone, ever, period. I'm very upset that this happened in the first place and want to make sure it doesn't happen again. This is a pretty big snowball of issues and we happen to be one of parts involved. I don't see any warnings from the wheel manufacturer or the spacer manufacturer. I've also already done more research in the last few hours than easily anyone else has or has posted. This is a big deal to me and I made sure to contact the OP personally and make additions to the website to make sure we can hopefully prevent this from happening again. Cheers, Joel

This was not the purpose of me posting. I was simply clarifying for those who asked and keeping everyone honest. Nothing more. I like you guys in general and the parts that you make. You'd know if I didn't.

[I<3Groceries]

Just like with anything else, regarding thermal expansion, a general rule of thumb is to avoid threading unlike metals. Nearly any mechanical industry (that knows what it is doing) abides that rule, when threading load bearing components, and in fluid delivery/control.

Not to mention, I would question the strength of aluminum to begin with. If you can imagine, the centrifugal force exerted when a car is busting ass around corners at a high rate of speed is quite excessive.

[Gringo East]

Originally Posted by Joel@CorkSport I don't understand this... I added this warning the minute after I got off the phone with the OP. I wouldn't want anyone else to put ANY lugnuts on with only 4 threads. I get the feeling that if I didn't do it I would still get some people complaining that we "still didn't have a warning on the site about it". Do you want pro-active or do you want nothing??? I don't want this to happen again, I don't want this to happen to anyone, ever, period. I'm very upset that this happened in the first place and want to make sure it doesn't happen again. This is a pretty big snowball of issues and we happen to be one of parts involved. I don't see any warnings from the wheel manufacturer or the spacer manufacturer. I've also already done more research in the last few hours than easily anyone else has or has posted. This is a big deal to me and I made sure to contact the OP personally and make additions to the website to make sure we can hopefully prevent this from happening again. Cheers, Joel

Joel,

I have issues with this post. Mainly, because I sent you guys a MSG via the Forums Monday night with the video and several pictures. Got a response Tuesday that someone from customer service would contact me. I really don't think you would have called unless I called Corksport first. Also, the conversation was dry and short. I felt like you were trying to educate me about your product that I no longer have anymore or would run. My lesson was learned at the event, and from talking to fellow enthusiasts . And I could also tell you wanted to get off the phone with me, which is cool your a busy person I understand and respect that. I'm glad this resulted in a warning for your customers. Honestly, thats all I wanted. But, one thing is for sure, you lost a customer.

Side note: I'm a shift worker, so calling on one of my days working isn't going to happen.

-Brian

[Crarrs]

Originally Posted by MS3johanna I You can order anything on their website. I ordered an LED taillight and a washer blade from them with my discount, over the phone. Didn't question it.

If you ordered over the phone and got whatever you wanted, there's a chance it's because you have the lady-bits mod.

For guys, your experience may vary.

[nindoja]

Thanks everyone for the mentions.
@Joel@CorkSport; I had failure of one of my lugs when removing the front driver's side wheel from the car. I've never put an impact to the lugs, and the one time I took it to a shop I was very strict that they not impact it.

That said, what would the damage be? I assume, based on the design, that it would round out the ends but not damage the threads?

I'll address the concerns that @JgamB; presented. I'm running 5mm JBR spacers up front and had issues with the lugs coming loose during a drag strip event. On one wheel, 3 of the 5 were finger tight. I tightened them to spec and kept running. A few more runs later and they were loose again.

Got home that night and torqued them back to 65ft/lbs and never had an issue again with them getting loose. I did not take the car back to the strip though.

Fast forward about a month and I'm at Gingerman Raceway doing a pre-race inspection. Some of the lugs weren't quite 65ft/lbs, but they were in no way finger tight. Retightened them with my torque wrench (Crafstman) and double checked them with @kritz;'s torque wrench. Everything looked good and worked fine during the track event.

Got home from EMWNM and went to swap my front brakes. 4 lugs came off the driver's side just fine when the 5th one sheared. Note, this was when taking the wheel off of the car. Since it was the last lug, I was supporting the wheel so it didn't have additional forces on it.

I've not yet taken the rear lugs off, but I will do that this weekend.

I filed a support ticket with CS and they have offered to send me a replacement lug. I just responded and asked them to wait until I get the others off the car before they take any action.

Honestly, I don't feel comfortable running these on the car and will be switching to gorilla lugs that I had sitting around.


EDIT: Not sure if it matters, but I'm running 17x9 PF01-SS with hub-centric rings and 5mm spacers.

[phate]

Originally Posted by Gringo East Just got off the phone with Joel. He told me about how 3mm spacers on stock studs were the max, about how there is away to measure the width to get how much of the stud needs to enter the lug so it won't break, as well that 5mm spacers + stock studs with steel lugs would have failed as well, also that they have sold hundreds of sets with zero problems, and that if I would like to get another set when they come back in stock that I could get a deal on them. Hey, I'm done it is what it is.

That's sad. My 5mm spacers with stock lugs are on a heavier car that was on stickier tires and (no offense) going much faster than what you were.

Same course, same day, guess I'm lucky?

PS - I don't run hub centric wheels or rings, either.