Is Road Hookless dangerous?

[spartacus]

Hookless was done solely to reduce manufacturing complexity and reduce cost. It has no benefit to the consumer.

Furthermore 72psi seems really low to me. I am under 70kg and that's right at where i want to be for a 25c tire. Many or most cyclists I come across are heavier than that, so unless they are on bigger tires the numbers can't add up.

Counterpoint, 72psi is plenty IMO, especially on these wide rims. It's no longer the age of 15mm internal width road wheel, it's now the age of wide rims.
I weight 66kg right now (though my race weight was 62kg). And My 25c Continental GP5000 gets 58psi on front wheel (rear is 28c). By linear scaling, 25c front and 28c rear at 72psi would be usable up to 81kg.

Then, rider heavier than 81kg but below 100kg can switch to 28c front and 30c rear to stay within 72psi. Even heavier riders also have option of 30c front 32c rear then 32c front,34c rear tires which are emerging on many fast road tires.

These are valid points and I'm not gonna argue against them, however you're at about 80% of the max pressure so you're relying on whatever safety factor is built into that spec (does anyone know for sure what it is?) plus the 20% so if you're fine with that and have high quality tires (you do) I agree that in all likelihood it's fine. I can and have run lower than 5 bar on my 25c but to me 5 bar is a sweet spot, and since I don't like to inflate before every ride, I can go a few days until the tire gets down to that 60psi or so then reinflate. But that's just me.

IMO though I would be far more concerned about the safety factor if using more questionable and supple tires like RH or what have you.

[pmprego]

Hookless was done solely to reduce manufacturing complexity and reduce cost. It has no benefit to the consumer.

I'm an engineer and IMO I would agree with this assessment.

Furthermore 72psi seems really low to me. I am under 70kg and that's right at where i want to be for a 25c tire. Many or most cyclists I come across are heavier than that, so unless they are on bigger tires the numbers can't add up.

if you're an engineer you know that the rules are clearly stated. if you need more that 72psi, use a bigger tire. If you don't want to ride that "low" psi, don't buy hookless. If you don't want to go bigger tire, don't buy hookless. for me, it's rather simple. I don't get what's the fuss about.

We engineers are trained to design in what is called a safety factor. In regulated industries where bodily harm is possible, 0 safety factor is completely uneaccetable and can open you up (rightfully so imo) to legal liability. Personally I am unwilling to accept anything less than 50% in this case*, due to manufacturing and QC variability in tires and rims. What you all choose to do is up to you.

*this is even assuming there is a safety factor built into the existing spec, a 2x safety factor would be ideal.

So, you wanted them to say "72psi is the maximum but we tested it up to 110 psi and it worked but 72psi is the maximum"? This way you would have the 50% factor and many people would simply go above the 72psi because... "hey... why not?! they tested it up to 100 and it worked"

hookless rim: 180 psi and it exploded.. https://www.youtube.com/watch?v=rr6w6CETe3Q&t=313s

so.. the "2x safety factor would be ideal" is checked i guess

[spartacus]

I'm an engineer and IMO I would agree with this assessment.

Furthermore 72psi seems really low to me. I am under 70kg and that's right at where i want to be for a 25c tire. Many or most cyclists I come across are heavier than that, so unless they are on bigger tires the numbers can't add up.

if you're an engineer you know that the rules are clearly stated. if you need more that 72psi, use a bigger tire. If you don't want to ride that "low" psi, don't buy hookless. If you don't want to go bigger tire, don't buy hookless. for me, it's rather simple. I don't get what's the fuss about.

We engineers are trained to design in what is called a safety factor. In regulated industries where bodily harm is possible, 0 safety factor is completely uneaccetable and can open you up (rightfully so imo) to legal liability. Personally I am unwilling to accept anything less than 50% in this case*, due to manufacturing and QC variability in tires and rims. What you all choose to do is up to you.

*this is even assuming there is a safety factor built into the existing spec, a 2x safety factor would be ideal.

So, you wanted them to say "72psi is the maximum but we tested it up to 110 psi and it worked but 72psi is the maximum"? This way you would have the 50% factor and many people would simply go above the 72psi because... "hey... why not?! they tested it up to 100 and it worked"

Yes I would love to know what the safety factor is so that I can make an educated decision. My suspicion is that it depends on the tire and rim combo with all of the manufacturing variability involved which is why I'm not comfortable with blindly running at or near the suggested maximum. Again; you do you, boo, argue with me all you want but I'm going to take responsibility for my own safety.

[pmprego]

if you're an engineer you know that the rules are clearly stated. if you need more that 72psi, use a bigger tire. If you don't want to ride that "low" psi, don't buy hookless. If you don't want to go bigger tire, don't buy hookless. for me, it's rather simple. I don't get what's the fuss about.

We engineers are trained to design in what is called a safety factor. In regulated industries where bodily harm is possible, 0 safety factor is completely uneaccetable and can open you up (rightfully so imo) to legal liability. Personally I am unwilling to accept anything less than 50% in this case*, due to manufacturing and QC variability in tires and rims. What you all choose to do is up to you.

*this is even assuming there is a safety factor built into the existing spec, a 2x safety factor would be ideal.

So, you wanted them to say "72psi is the maximum but we tested it up to 110 psi and it worked but 72psi is the maximum"? This way you would have the 50% factor and many people would simply go above the 72psi because... "hey... why not?! they tested it up to 100 and it worked"

Yes I would love to know what the safety factor is so that I can make an educated decision. My suspicion is that it depends on the tire and rim combo with all of the manufacturing variability involved which is why I'm not comfortable with blindly running at or near the suggested maximum. Again; you do you, boo, argue with me all you want but I'm going to take responsibility for my own safety.

which "regulator"/company tells the real limit of a product? at least some specialized frames have 125kg weight limit. does it mean that at 126kg it breaks? you get no company stating the real limit. you can and I have nothing against someone saying that they want to use a product because they simply don't like it (for whatever reason). saying this is bad because they do not state what is the real limit extends to basically any product on earth.

[spartacus]

We engineers are trained to design in what is called a safety factor. In regulated industries where bodily harm is possible, 0 safety factor is completely uneaccetable and can open you up (rightfully so imo) to legal liability. Personally I am unwilling to accept anything less than 50% in this case*, due to manufacturing and QC variability in tires and rims. What you all choose to do is up to you.

*this is even assuming there is a safety factor built into the existing spec, a 2x safety factor would be ideal.

So, you wanted them to say "72psi is the maximum but we tested it up to 110 psi and it worked but 72psi is the maximum"? This way you would have the 50% factor and many people would simply go above the 72psi because... "hey... why not?! they tested it up to 100 and it worked"

Yes I would love to know what the safety factor is so that I can make an educated decision. My suspicion is that it depends on the tire and rim combo with all of the manufacturing variability involved which is why I'm not comfortable with blindly running at or near the suggested maximum. Again; you do you, boo, argue with me all you want but I'm going to take responsibility for my own safety.

which "regulator"/company tells the real limit of a product? at least some specialized frames have 125kg weight limit. does it mean that at 126kg it breaks? you get no company stating the real limit. you can and I have nothing against someone saying that they want to use a product because they simply don't like it (for whatever reason). saying this is bad because they do not state what is the real limit extends to basically any product on earth.

I don't know what safety factor they put in which is why I'm not comfortable going to the max recommended, especially with many reports of tire blowoffs. I also would not ride a frame if the weight limit was equal to my weight. I believe with tubeless tires that the safety factor is likely less than the variability (leading to potential blowoffs) due to certain tire and rim combinations just based on what I've seen on forums and the like.

Also FWIW in many industries there are standard and accepted safety factors, it's not just up to someone's whim, and these safety factors increase or decrease based on the quality of the parts and systems in question as well as their potential consequences of failure... WRT tubeless tires and rims I think we all know the tolerances and spec can sometimes vary, and to me, the tire coming off the rim is not an acceptable risk therefore I demand a high safety factor.

[jlok]

I think we can easily avoid those air bombs with drilling small drain holes in the rims, but not sure how many brands offer them (e.g. . Light Bicycle). ENVE should be the last one because they only want to mold holes, hence selling such a valve nut.

They can mold spoke holes but not drain holes?

[Cemicar]

I think we can easily avoid those air bombs with drilling small drain holes in the rims, but not sure how many brands offer them (e.g. . Light Bicycle). ENVE should be the last one because they only want to mold holes, hence selling such a valve nut.

They can mold spoke holes but not drain holes?

They should prepare holes in molds so we have to wait for the next update for any tweak (the last one is 2022).

[jlok]

This is an oversight for a brand that have been advertising the use of tubeless tires for many many years.

[ooo]

Pressure Relief Valve Stem Nut is not exclusive Enve design, looks like it is an OEM product:

https://primebikecomponents.com/products/pressure-release-valve-stem-nut-pair

[aeroisnteverything]

hookless rim: 180 psi and it exploded.. https://www.youtube.com/watch?v=rr6w6CETe3Q&t=313s

so.. the "2x safety factor would be ideal" is checked i guess

So that's interesting, right? No one inflates to 180 psi obviously, but when a heavy rider rides over a pothole at high speed, what is the max localized pressure inside the tyre at the moment of impact? Could it exceed 180 psi if the tyre is initially inflated inflated to 70-80? I have no idea. But manufacturers should test to those limits.

[yingyu]

hookless rim: 180 psi and it exploded.. https://www.youtube.com/watch?v=rr6w6CETe3Q&t=313s

so.. the "2x safety factor would be ideal" is checked i guess

So that's interesting, right? No one inflates to 180 psi obviously, but when a heavy rider rides over a pothole at high speed, what is the max localized pressure inside the tyre at the moment of impact? Could it exceed 180 psi if the tyre is initially inflated inflated to 70-80? I have no idea. But manufacturers should test to those limits.

No... air pressure propagates at speed of sound, and one would need to compress the air volume to less than 50% to get 80 -> 180 psi. The rim would be shattered first.

[Mostlyharmless]

its safe.. tires can come off any rim during blowouts

Nah ah if u r riding old and trusty tubulars


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[spdntrxi]

its safe.. tires can come off any rim during blowouts

Nah ah if u r riding old and trusty tubulars


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do your research.. you are wrong

[TobinHatesYou]

Tubs don't even need to blow out to come off the rim.

[Hexsense]

hookless rim: 180 psi and it exploded.. https://www.youtube.com/watch?v=rr6w6CETe3Q&t=313s

so.. the "2x safety factor would be ideal" is checked i guess

So that's interesting, right? No one inflates to 180 psi obviously, but when a heavy rider rides over a pothole at high speed, what is the max localized pressure inside the tyre at the moment of impact? Could it exceed 180 psi if the tyre is initially inflated inflated to 70-80? I have no idea. But manufacturers should test to those limits.

No... air pressure propagates at speed of sound, and one would need to compress the air volume to less than 50% to get 80 -> 180 psi. The rim would be shattered first.

Yeah, that's how using foam insert and lower tire pressure can make rim crack easier.
Air propagates very fast. Using enough tire pressure to provide support needed to prevent pinch flat and you are gold.

Then some riders decide to add form insert into allroad/cx/gravel/mtb wheels to run very soft tire pressure thinking the foam will take the impact.
But foam insert doesn't spread the load like aired tire do. So, when there's an impact, the load is still a point load into the rim. More salt to the wound, foam insert push hard at rim bed area, instead of the reinforced rim hook/wall.
Is there any way to make foam insert spread the load all over the rim like a tube?