6ul Wheel Failure

Hjt · Postby **Hjt** » Sun Mar 31, 2013 5:03 am

Similar car and times as my vehicle. Ill have an update shortly

mazmad · Postby **mazmad** » Sun Mar 31, 2013 7:51 am

Yeah wasn't there when yours happened Hayden but when I saw his that was my first thought...and of my wheels.

greenMachine · Postby **greenMachine** » Sun Mar 31, 2013 10:51 am

mazmad wrote:Think 225 semis. 15s.

Thanks mm

greenMachine · Postby **greenMachine** » Fri Jul 05, 2013 11:20 pm

Anything to update?

:mrgreen:

MINX · Postby **MINX** » Sat Aug 03, 2013 7:09 pm

from States
massive failure on track

TieNN89 · Postby **TieNN89** » Sat Aug 03, 2013 8:10 pm

Not another one

toppertee · Postby **toppertee** » Sat Aug 03, 2013 9:35 pm

As Quoted

If you received your wheels on or after May 2012, they are Gen 3's. Not the discontinued Gen 2 that some people have broken or cracked. The last Gen 2's shipped Nov 2011.

The total of all reported 6UL failures (15x8 & 15x9) represents roughly .0004% of all 6UL's produced since 2006. That is not a typo.

According to our research, roughly 85% off all 6UL's produced are used in competition or HPDE with high performance or race tires. The significance of that number is that they are pretty much all being thrashed on the track. Very few end up used solely on the street. In 2011 we began the review process for updating the 6UL design to gen 3. Knowing which loads/stresses to focus on allowed our engineers to more precisely tailor the strength to weight ratio. The few that have broken have all been replaced at no charge even though most both voided and were beyond the warranty period.

In short, we are seeing very light cars generating peak transient cornering forces of a car that weighs about 3x more. Industry standards call for a weight rating and test protocol roughly equivalent to 1.8x actual vehicle weight for a 4x100 wheel, a theoretical 4400 lb car (1100lb per wheel). The gen 2 design exceeded that standard but it still wasn't enough for a handful of racers. Knowing what we know now, the next step was to engineer radial fatigue resistance (cornering) for about 4x the weight of the actual car, or about 8800 lbs.

Seeing that only a few have broken, we know the previous gen 2 design was very close but a few have surpassed its rated max load with a possible combination of impacts, fatigue and heat cycles. We can deduce that the industry standard rating was very close but needs to be surpassed if a lightweight race wheel is to meet the actual loads it will see. So that's what we did.

The Gen 3 15x8 and 15x9 revisions fully address the reported 15x8 and 15x9 failures with a higher max load rating and additional validation test protocols including an independently run "Radial fatigue" test that simulates about a 4400lb car cornering at 1G for a few hours. Our internal FEA testing went well beyond those numbers. The Gen 3's have gained a few ounces of weight as a result of these revisions.

The 15x7, 15x7.5 and 15x10 were always Gen 3 designs and have had no reports of cracks or failures.

Our own race team currently uses a few gen 1, mostly gen 2's and now a few gen 3's. The equivalent of about 2000hrs combined HPDE, testing and racing since 2006. This, on our way to several national championships including winning the 2011 25hrs of Thunderhill. The point is we race what we sell and continue to learn and improve everything we offer through racing and customer feedback. It is a closed loop R&D process meaning we pay attention to how the wheels perform and make changes when we see the opportunity to improve.

mazmad · Postby **mazmad** » Sat Aug 03, 2013 10:01 pm

I have faith in them, would have bought another set if they had the stock at the time.

Mr nanotech · Postby **Mr nanotech** » Sun Aug 04, 2013 7:20 pm

I don't own a set but I don't see any issues here. To be honest, all wheels can fail. It's just a fact of life. I've seen Rays, Work, BBS, Wedssport.. you name it, fail. But just because it CAN happen doesn't mean it will happen. It's such a rare thing to happen and sure you might here of 5-6 cases of the same wheels failing but then cross that with how many units have been sold.
You'll find the numbers will be staggeringly low. So low that the failure rate isn't worth thinking about. The fact of the matter is that nothing is perfect and regardless how well things are engineered, nothing is indestructible.
You have to factor in other contributing factors. How do you know the wheels were not dropped or damaged, fractured or cracked. A genius at a tyre fitting shop may have dropped a wheel leaving a very fine hairline fracture that may not be visible to the naked eye, but tear apart when stress is added to the unit.

Point is, it's not something to be worried about.

mazmad · Postby **mazmad** » Sun Aug 04, 2013 7:35 pm

I am assuming this is from Emilio @ 949 racing....
The total of all reported 6UL failures (15x8 & 15x9) represents roughly .0004% of all 6UL's produced since 2006. That is not a typo.

Suspense · Postby **Suspense** » Sun Aug 04, 2013 10:58 pm

Just an observation but that wheel pictured above looks like it got pretty heavily acquainted with a curb on one side.

Hjt · Postby **Hjt** » Mon Aug 05, 2013 12:24 am

Point is, it's not something to be worried about.

I won't worry the next time my wheel falls apart mid corner.

mazmad · Postby **mazmad** » Mon Aug 05, 2013 8:21 am

What wheels are you currently running Hayden?

deviant · Postby **deviant** » Mon Aug 05, 2013 11:44 am

Suspense wrote:Just an observation but that wheel pictured above looks like it got pretty heavily acquainted with a curb on one side.

Might have happened once it parted company with the car.

Hjt wrote:
Point is, it's not something to be worried about.

I won't worry the next time my wheel falls apart mid corner.

I spent 5 or 6 years as a flaggie at my local circuit and missed maybe a handful of events in that time. I have been involved in motorsport in some capacity for 15 years.

I have seen ONE wheel failure in that time.

I have seen plenty of brake pads and discs fail, CV joint failures, prop shaft failures, diff explosions, clutch failures, engine blow ups, throttles jamming, suspension and related parts fail, tyres failing....and more than a fair share of brain failures.

Just one wheel failure though.

I am sure it was a bit of a shock to lose a wheel mid-corner but any number of things can fail on your car. That is the game you play when you go on track.

Mr nanotech · Postby **Mr nanotech** » Mon Aug 05, 2013 3:43 pm

deviant wrote:I have seen plenty of brake pads and discs fail, CV joint failures, prop shaft failures, diff explosions, clutch failures, engine blow ups, throttles jamming, suspension and related parts fail, tyres failing....and more than a fair share of brain failures

This was my point. The chances of a wheel failure happening on track are so improbable that there is a far greater chance of all of the above happening to you before a freak accident like this. It's like saying you refuse to go outside on the off chance you might get struck by lightning. The probability is just too low to worry about.