I’m a little confused now. The tire blew out from a hooked wheel, is it? Because, as far as I know, Roval is, and always was, hooked.
There was, in the past, a thing about them being tubeless-ready/compatible, but that is a whole different thing.
Were they?
Per that article it states
regardless, if they were hookless or hooked - I saw in a span of 4-years (2) different riders running tubeless that had the tires come-off and a redesign from Roval on the rim’s.
Definitely hooked.
Additionally, the failure that led to them dropping tubeless was about the rim pressurising during a rim failure and effectively exploding.
Nothing to do with tyres randomly rolling off the rim.
Either way, nothing to do with hookless
Imagine that, hooked wheels suffer failures too.
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Nothing you quoted there would imply a hookless design. Roval does not and did not sell hookless road rims.
But you bring up a good point about some people telling anecdotes and blaming design features when in actuality they have no idea what they’re talking about.
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…and that’s exactly my point.
It’s all being dumped into the hookless account, which, I don’t think is the case.
Now, a random thought. Would the safety - or odds of something happening - be reduced by using an inner tube on hookless? It’s not “against the rule”. I don’t remember seeing a safety warning against the use of inner tubes. And given that the TPU ones are pretty good, I don’t know… maybe…
You can indeed use tubes with hookless and do, apparently assist with tyre retention.
Doubtful. You can use a tube, but the rims require a tubeless bead. Using a tube does not enhance the bead to rim interface. If anything, I would worry that the tire would be less secure, if the tube is not applying equivalent lateral pressure directly on the bead.
Well, not sure this is a true negative for hooked considering that specific case was a legit “problem” in design and function. Unintended consequence and definitely not what the engineers aimed to have happen. So I don’t think it’s appropriate to use that example as one that knocks hooked rims. Spesh remedied that issue their new versions are proper tubeless compatible and still hooked.
Bottom line, that case hardly indicts hooked rims IMO.
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- OK, that makes sense from that data, at least per my experience and pressure calculators.
@teddygram wasn’t describing the issue with the gen1 rapide wheels that saw tyres dismount when the rim exploded, he claims the tyre just randomly dismounted. That’s as valid as anyone else’s anecdote about witnessing a Hookless failure.
That along with the original Sagan failure as well as Fred Wright and Derek Gee’s hooked tyre dismounts in PR last year, it shows that tiny hooks do not guarantee tyre retention.
No one has demonstrated cause and effect with regard to the high-profile failures on hookless rims, as such no one knows they are the result of hookless, they are just linking potential coincidences.
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Good point. Hard to keep the longer history of this all in mind and crossing wires (or hooks 
) is all too easy, at least for me. 
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Yes those are hooked like everyone posted.
I’ve had a hooked tire failure from a TIRE BEAD that stretched - Hutchinson Sector 28 tires.
HOOKED ENVE 5.6 Disc.
Hutchinson Sector 28 tire bead stretch and fail 19 miles in the middle of nowhere:
no cell coverage, group ride thankfully. Took a pic while waiting for an hour to get picked up:
Back at home:
Tire installed a week earlier, the fact it went on so easy and all these bubbles should have been a warning sign:
New tire, 3 rides on the kickr, an hour outside, and then that ride.
Pressure set to 60psi.
I’ll never buy/ride Hutchinson again!
ENVE had a picture of the tire issue:
Blow off is possible on hooked rims too, as I proved with those not-fit-for-tubeless Hutchinson Sector 28 tires.
So thats why tire beads have gotten so inflexible! I originally posted it here:
For completeness I’m adding that to my list of tubeless experiences in this thread, although the tire industry has long since moved to inflexible tire beads.
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Used on the Kickr???
No on wheel-off Kickr v3 direct drive.
Thought so… was just confused for a second.
Well, there’s your problem. The tire was slacking in the pool.
Talk about pampering your bike!
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spa day!
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Is there? What is the measured increase? I’m sure the UCI would love to know! The only thing I’ve seen that’s even close to data in this entire thread is Josh Poertner’s quote from the Slowtwitch article (copied again below for context) and even that isn’t really data - what combos were the blow offs? Were they combos that are still OK under the new updated ETRTO guidelines or were they in compliance at the time but are now out of compliance?
Everything else in this thread is anecdata. Likely the only people who have proper data on this are the wheel and tyre manufacturers who will have done their own testing, and the ETRTO. I would say it’s a safe bet that if any of that testing showed there was a “measurable increase in the chance of catastrophic failure” then these wheels would never have got to market in the first place or would have been pulled the moment there was evidence they weren’t safe. Similar to how Specialized flipped at the last minute to say that the generation of Rovals referenced above weren’t tubeless compatible - these brands certainly want our money, but they all have legal teams and I can only imagine the lawsuits that would follow if they knew they were selling unsafe wheels and carried on doing it anyway.
I will say that in the 100+ tires we’ve tested over the last few years on 40+ wheels, we’ve had 6 blowoffs in tire seating, 3 blowoffs below the 110% ISO test, and 1 blowoff of a wheel just leaning against a wall. Every single one of them was on a hookless rim and following ETRTO guidelines
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Well therin lies the rub…you have an independent group that develops standards saying one thing and manufacturers saying another thing, both of which have their won data.
Personally, I know that for our company, any testing criteria is the bare minimum we strive to meet. We usually far exceed them, as well. They are the lowest threshold, not an end goal. The fact that some manufacturers are saying combos that are below that recommended minimum does not fill me with confidence.
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I’d consider Josh’s post data; 10 failures out of 100+ in the hookless column, zero in the hooked column. I would consider that a measurable increase in the chance of catastrophic failure. At a minimum, it seems clear that the safety margin for some of these tire-rim combos on hookless is razor thin and easily crossed via common user error.
More to the point, in that article Josh makes it pretty clear that he prefers hooked for any application where tire-to-rim delta is <5mm, and feels there are performance gains to be had from such combinations. No we don’t have the raw data, but as I posted previously I’m happy to trust the expertise of genuine experts (like Josh) and don’t feel that I need to do my own research, especially when the consequences of pushing this particular envelope are potential injury or worse.
I’m honestly curious why many here seem bent on defending wide hookless tech or suggesting this is all a conspiracy. Do you already own $$ Zipps and are upset that you shouldn’t run 28s? If so, thoughts and prayers.
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