BTW, BRR is far from perfect, but it’s the best we have.
IMO, drum testing or testing on a velodrome gives useful info but is not the “end all, be all”
But wouldn’t a tire blow off earlier under the same inflation pressure due to other forces, such as hard cornering? So a tire that may resist 80 psi in a workshop without blowing off, could blow off at 70 due to friction heat and cornering forces.
Yes, l don’t think l would trust a lab experiment to accurately assess at exactly what psi a tire would blow off a hookless rim while actually riding in the real world. But, a series of tests, if they are all performed consistently, could possibly provide some info about the relative (relative to one another) safety of these set ups. But, as always, it is always wise to “use at your own risk.”
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I second both these prior posts, 100%.
What we really need is for a small group of people to gear up in full protective gear, pump the tires up to 80/85/90/whatever psi and go for a hard paceline group ride on variable roads and see if anything happens. I’m joking of course but I’m with others in that if the testing is not representative of real-world riding, it can only go so far.
the lack of sealant in testing is very surprising to me (because wouldn’t it help prevent blowoffs, maybe?). just because everyone else tests that way, why does that make it the right thing to do? clearly the only reason brands test without it is to avoid the hassle/mess/cost, right? if the testing wanted to replicate the system we all ride with, there would be sealant in there. 100%.
I sort of did this and noted it above…Sample size of 1 though
Also there’s the possibility that different sealants might have different results, which creates a bunch of permutations they don’t want to spend time on.
Adding sealant would quickly make a very big test matrix on its own:
- Which sealant?
- How much sealant?
- How long since it’s put in?
- How is it put in (through valve or poured in)?
It would make good sense to do some comparison tests where you check if putting in some sealant changes your no-sealant result. If it does, you probably need to dig more into the matrix created above, but it could escalate quickly.
Sometimes it’s worth taking a step back and ask “what are we trying to prove here ?”
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100% this. And I thought that it was ‘are hookless tyres likely to pop off if a user accidentally over inflates by a 10PSI over the low 70psi limits’.
And in this case then in every real world scenario that is on a wheel with sealant in. So if we do a test of a couple of tyres with and without sealant and in each the with sealant is 5psi higher for the blowoff then we can be fine with the data from the tests that don’t leave @E_DUB looking like he is an extra from Ghostbusters.
I fear I have opened up “The Box” with this simple little test…
From my view: that the wheel manufacturers have pushed safety responsibility onto the tire manufacturers. Probably some heated conversation between them behind closed doors.
This popped up in my FB feed just now.
“My Hunt Wheel Exploded”
Yikes…
But that’s not really a hookless failure is it?
The whole thing is…….if we hadn’t have hookless road bike wheels this whole discussion wasn’t needed.
Jeroen
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It’s not. But, it goes to the point of lack of awareness/education on hookless by buyers and bike shops.
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Sorry, I might be a little daft and can’t read 175 comments.
But it seems like a wheel without vents that someone way over inflated.
Wouldn’t this occur on hookless or not?
He stated that in the article. He had the wrong tire and the pressure climbed to high in the sun. That’s part of the discission up-thread. The small margin between max recommended pressure and blowoff pressure on some tire/wheel combos. Yes, it could occur on hooked rims but the margins wouldn’t be so close. You have more room for error I think. But I have have seen it on hooked rims sitting in the sun also.
This thread is really an interesting discussion with some very smart people
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But that’s not just a tire blow off. That’s a complete rim failure.
Wasn’t the whole debate that tires would blow off the rim. Not the entire wheels would explode?
I see what you mean now. I think the consensus was upthread that when doing their blowoff tests that a rim can be damaged. At least that’s what I took from it. Look back over the thread, there is some very intelligent and well thought out discussion on this.
I used NotebookLM to read the entire thread.
The thread does not explicitly state that a blowoff can damage a rim. However, it does discuss the “potential for catastrophic failure” associated with hookless rims, particularly when they are used outside of their "narrow optimal operating windows
I realize that’s probably cheating…but my understanding was that the risk was the tire blowing off, not blowing up the entire rim. Which I think would also occur with a hooked rim also…maybe even more likely because they super valuable hook would grab the rim before the tire came off.
I’m not trying to continue beating the dead horse. I think peoples concerns about hookless are not without merit. But the facebook post seems like another example of wrong tire, pressure, and maybe a bad rim that resulted in a blow off.
Every wheel issue that happens to be hookless can’t be blamed on hookless. Otherwise it really is the call back to “Every wreck was because they had disc brakes” or “they never would have crashed if they didn’t have that crazy road tubeless!”
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