Open tubular failures on ENVE wheels:

[bm0p700f]

Clanago, it not sharp/rough edges as such. On the SES rim the bead hook is simply not round. It is designed that way. In my opinion no tyre is safe to mount as the rim does not conform to any standard for tyres. No tyre manufactuer makes any tyre with a bead hook like ENVE's in mind.
this is not an open tubular problem. Some tyre manufactuers do reinforce the bead area because they know some rim manufactuers have not got a clue. That should not be needed and does not make the tyre safe to use on the rim. If this was the car industry there would be class action lawsuits. This however is the laxidayical bike induystry where anything goes.

[Calnago]

Well, the issue is the cutting of the tires’ sidewall at the rim bead area by the rim bead. If you want to call it “not round” that is fine by me.
And it’s not like every supple tire mounted on an ENVE rim is going to fail... there are plenty of folks running such combinations just fine. But the issue is that it “could” happen in cases where those edges are perhaps, a little less round than they should be. Some have been calling them “sharp”. But please, I’m not getting into another semantics war.

[bm0p700f]

I know what the issue is. The bead hook is not round. That cuts into the tyre. It can cut into any tyre, whch tyres it cuts inmto depnds ont he tyre and how much load is placed on the tyre, pressure i.e how much contact it has with the rim. Some tyres are prone to this than others. I understand the issue very well and published on my website but removed as I thought it was defamatory due to lack of proof. I turns out I was right.

There have been some IRC warranty issues on ENVE rims which is what drew my attention to this but not many and not enough to draw conculsions as my sample size was too small.

Look at my post of the first page. The drawing of the SES rims that ENVE publish says it all. Look at the mavic bead hook and spot the difference. It is a design problem not a manufacturing issue with some rims. I dont think you see that.

The fact that not every tyre fails is besides the point. That the bit you dont get. There is a design issue that increases the risk of failure. That why no tyre should be used as no tyre can be considered safe due to the fact there is increased risk. If some tyres are O.K due to reinforcement then that still is not fine as the rim is still not standards compliant. I understand the issue very well and as a importer of tyres I really have too understand it.

[Calnago]

Look at my post of the first page. The drawing of the SES rims that ENVE publish says it all. Look at the mavic bead hook and spot the difference. It is a design problem not a manufacturing issue with some rims. I dont think you see that.

I do get what you're pointing out and have since you posted it. I just don't think the crux of this issue is primarily related to the fact that ENVE's bead edge is admittedly a more "squared" profile than Mavic's. Whether or not ENVE's design is optimal or not is another matter; I've seen a whole lot of designs in the bicycle industry that are less than shall we say, "optimal". Whether it is safe or not is what they need to address. The two corners of the bead could very well have been spec'd to have a smooth soft radius on them, obviously not a complete semicircle edge shape, but nonetheless one without sharp edges. But getting those nice smooth edges out of their existing manufacturing techniques really does seem to be problematic, and that could be a very difficult and expensive process to correct. They have got themselves into a bind here at the moment, and I think the fallout for them could be much greater than they've anticipated. They've acknowledged publicly that tires are failing on their rims. Blaming it on the tire manufacturers is not going to fly. Period. This is on them. Those edges can be sharp. Should tire manufacturers all of a sudden be forced to produce only garden hose stiff tires, reinforced with steel belts along the sidewall so that ENVE can merrily go about their business by continuing to produce rims with could potentially cut through the nicest tires currently available. I mean, life is too short to ride crap tires.
Lots of companies, where people's safety is concerned even remotely, especially where it is foreseeable that an actual death could occur as a result, would issue a recall on all potential product that could be affected. I think that could adversely affect ENVE to the point they would fiancially never recover. I'm a bit surprised a recall hasn't actually been issued yet, quite frankly, and perhaps they are just quietly keeping their fingers crossed that nothing serious happens to anyone due to this issue. This is the bicycle industry after all, and sometimes I think they believe that no one is watching, or cares, about this little bicycle business stuff. But keeping their fingers crossed is not going to absolve them of liability at this point if something like that does happen. I'm sure they are wracking their brains right this moment trying to figure out how they can change the manufacturing process to better round off those edges from what they are now. Good luck to them.

The ironic thing here is that both Mavic and ENVE are owned by the same parent company at this point, Amer Sports, and it's no secret that Amer would like to unload both of them if they could. This is definitely going to throw a wrench into any sales negotiations that might transpire. No one wants to acquire a huge question mark of a liability, let alone a company that isn't performing financially.

The outcome of all this will be interesting to watch unfold.

[youngs_modulus]

The ironic thing here is that both Mavic and ENVE are owned by the same parent company at this point, Amer Sports, and it's no secret that Amer would like to unload both of them if they could.

It may not be a secret, but I (for one) hadn’t heard that Amer is trying to sell both Mavic and ENVE. Got a cite?

[guyc]

They’ve sold Mavic as of yesterday. Enve wasn’t part of the sale:

https://www.bike-eu.com/home/nieuws/201 ... m-10135527

[youngs_modulus]

Wow! Thanks for that breaking news item!

[AJS914]

The industry just voted to adopt the Mavic UST standard. We'll see if Enve gets with the program.

[thePrince]

I'm a little late to the thread...but

1. Completely agree with Calnago (I don't always ) that "open tubular" is dumb. FFS it's a clincher. An overweight man who needs a bra is not a woman. Still a man.
2. I don't care what Vittoria calls their clinchers. They have a great ride quality and do not flat unless it is wet outside.
(2.5. Now that we have Orange Seal and cell phones, tubulars are that much more attractive.)
3. Never understood the allure of ENVE wheels. Lightweight aside, they are the most expensive wheels out there and I don't understand one reason why you wouldn't buy rims from Light Bicycle, add Tune hubs and CX ray spokes, and save yourself a ton of $$$.. Must be because they are "The ultimate everyday carbon fiber cycling wheelset and choice of Team Dimension Data." LOL

[pdlpsher1]

Saw this in the news today.

Challenge's response could be summed up as "it's not our tires, it's their rim." In particular, Challenge said that Enve's SES model rims have a sharp hook that can cut sidewalls. It said its investigation found the problem can occur with a variety of tires, not just its models.

"Enve's SES have two sharp (<0.2mm) radii in their hooks, that leave two parallel cuts about 0.5mm apart, around the entire radius of our (and other company's) tires, at around 3-4mm above the bead," Challenge said.

Challenge said that because of the hook radius, the SES rim model does not comply with current international standards and said it has notified Enve of the situation. The company is warning consumers to not use Challenge tires on any rims that do not comply with the "2019 ETRTO, past ETRTO or soon to be released ISO 5775 global standards for tire and wheel fit."

On its website, Enve said all its rims comply with ETRTO standards, with the exception of its M Series M60 Plus and SES 4.5 AR Disc rims. The website doesn't say exactly how or why those models don't comply with the standard.

Enve's Jake Pantone told BRAIN on Friday that he couldn't comment on the situation. "We can't comment at this time, but we'll be in touch soon," Pantone said in an email.

[guyc]

Sounds like Enve have a problem then.

[LionelB]

Clearly they do. Never liked their rims anyway and never used any of their clinchers.

[wheelsONfire]

Off topic, but anyway. When i spoke to a company selling custom made wheels, they told me that some rims and some tires don't play well (tubeless).
Meaning that some combos increase risk for tire burp. That means tire risk to come off rim while riding.
I had no idea of this, but learned the bad way.
To me it seems that these two problems (sharp rim beads and tire burps) are leading (worst case) to same outcome.

Part from that, i now begin to wonder if this bead hook matter (round vs oval/ sharp) was giving birth to "the hookless rim bead"?

I have been thinking of a new set of wheels for long now (tubeless/ clincer) and all of a sudden, this thread makes me feel like tubulars might be worth the hassle anyway

[spdntrxi]

you cant place the blame on just one company.... at the time there was next to no standards so you cant jump in the time machine and change history. If you remember your history the Vittoria Corsa Speed open TLR had a redesign and guess what for........... exactly for this issue.

[guyc]

True. But when one company lays the blame at the doors of tyre manufacturers with no focus on their own possible shortcomings it does wind people up.