A facebook user posted pics of his 6UL wheel breaking on track on Sept. 1 2019. That's 7 years after the issue was first reported to 949/Emilio. Check your wheels.

 

Newsflash: wheels used regularly on track will crack. You should regularly inspect your track wheels, and 6ULs are not unique in this regard. Early 6ULs were more prone to this, but later generations have been performing within expected parameters.

EDIT: Since the OP couldn't be bothered to link anything, here is the m.net thread:

https://forum.miata.net/vb/showthread.php?t=701617

Owner has a legit gripe IMO, wheels should last through several sets of tires barring abuse. Important to note that these are the 17" wheels, not the 15" wheels that had the issues 7 years ago. As far as I'm aware 3rd and 4th gen 15" wheels have been lasting as long as would be expected. Looks like there may need to be some changes to the 17" wheels.

 

Are people dye checking them?

That's how i check my props for cracks i can't see.

 

"Wheels are a wear item" bla bla bla
My experience, and that of many I know, is that other wheels last much longer than 6ULs. My second gen 6UL's made it through about 10 HPDE track days - with no curb impacts, running street tires - before cracking. I was told to pound sand when I voiced my concern, like pretty much everyone else. 949 may make some good stuff, and I'm glad for their contribution to the community, but I stay away from 6ULs because I cant afford to replace them every season and their service if something breaks is awful. The only reason I felt comfortable buying XIDAS was because they're made by Tractive.

Totally unscientific as well, but put "miata wheels cracked 6ul" in google and see how many more people have issues with this wheel than anything else - TRM, Advanti storm, etc. have almost nothing, while there are pages of people with cracked 6UL's. One recent thread suggests a serious design flaw in the current 17x9 6UL, as 3 separate customers in that thread alone had 3-4 of their wheels cracking in the same spot.

 

A Miata is a car that weighs 1/2 of some other track day cars. We don't see a 7 year track record of cracks and catastrophic failures for other brands. At least Emilio is consistent about offering excuses.

 

Wheels are a wear item. You should change your 6ul wheels every time you change tires.

 

Your miata is a wear item. Replace it every 3000 miles.

 

Be careful out there.

 

Saw the pictures on FB, it’s gnarly couldn’t just imagine going at speed and literally have the whole wheel fall off, I think 949 should take a step back and reassess how they are making their wheels.

 

That's laughable. I really hope that was a joke(kinda hard to tell sarcasm from text). I have 15 year old Kazera wheels on my track Miata and they haven't failed.

There's really only two possibilities, either it's a design flaw or it's a manufacturing (metallurgical) issue. Either way, 949 is liable.

 

Chinese wheels will be chinese wheels, man.

 

They way some of you guys act I’m suprised were not throwing miatas away ever season...

 

I dunno about you guys but I throw all my knowledge out and start over in DE1 every season. Brains are a wear item.

 

If you are running 6UL's you just might need a new brain after the wheel fails and you crash.

BTW, more broken and cracked 6UL's are being posted on facebook. Repeat after me, consumables, and drink the 949 Kool Aid

 

Hard to tell how many are just regurgitated 15"s from 5+ years ago.

 

Some might be older cases but some were just a few weeks ago. If you feel lucky roll the dice.

 

The 15s seemed to have an issue that was fixed, right? I'm unaware of the latest-gen 15" 6ul's having this mode of failure (correct me if wrong) Does seem odd they didn't apply that fix to the 17" version.

 

I'm not aware of all the sizes involved. There is a thread on miata.net. Seems it involves at least two wheel sizes that are different product lines. Here's what I've noticed, the wheels all crack in approximately the same area. This suggests to me that it could be a design issue. Questions that need to be answered is who designed the wheels and what were the design specs? The next question is whether the manufacturer is actually producing them to the material specs.

 

Just play it safe and replace your wheels with your tires. Simple, forehead.

 

i'll stick to my konigs.. thanks.