Continental GP 5000 S TR popped off (Cadex AR 35 wheels)

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Nickldn
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by Nickldn

stjepan wrote:
Thu Feb 09, 2023 7:29 pm
The rim seems fine to my untrained eye, it has no visible marks of defect or anything really.
Apart from the lack of tyre hooks of course. :D :D

But seriously, as much as I want the new Propel, its Cadex hookless rims put me off. Your experience just reinforces my view.
Giant Propel Advanced SL Red Etap 11s Easton EC90 wheels CeramicSpeed BB Zipp SL70 bars 6.5kg

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Mr.Gib
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by Mr.Gib

stjepan wrote:
Thu Feb 09, 2023 7:29 pm
Mr.Gib wrote:
Thu Feb 09, 2023 7:15 pm
I just hate seeing this. Guess I will abondon my plans to go hookless.

Yes, interesting that the blow-off happened at the valve, but so what? Even if the tire wasn't properly seated (which I doubt), it shouldn't even be possible for it to go over the top, certainly not at the stated pressure. Rather, the tire should settle in place after a couple of rotations on the road. Something is seriously messed up with that tire or less likely the rim.

Question, was the tire too easy to get onto the rim? The OP has lots of nice wheels and I assume knows what a tire that is too loose feels like, and how to properly install?
...
To your question - it wasn't too easy to fit them, I had to resort to tire levers in the end to get them on completely (both tires).
Eff me. So a top tire from an industry leading brand goes on nice and snug, everything else to spec and in good order, but the tire still blows off. What's a guy supposed to do? So much about this industry makes me wonder if we aren't guinea pigs for some company's beta project. Sticking with hooks - forever.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

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easyv
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by easyv

Mr.Gib wrote:
Fri Feb 10, 2023 2:35 am
stjepan wrote:
Thu Feb 09, 2023 7:29 pm
Mr.Gib wrote:
Thu Feb 09, 2023 7:15 pm
I just hate seeing this. Guess I will abondon my plans to go hookless.

Yes, interesting that the blow-off happened at the valve, but so what? Even if the tire wasn't properly seated (which I doubt), it shouldn't even be possible for it to go over the top, certainly not at the stated pressure. Rather, the tire should settle in place after a couple of rotations on the road. Something is seriously messed up with that tire or less likely the rim.

Question, was the tire too easy to get onto the rim? The OP has lots of nice wheels and I assume knows what a tire that is too loose feels like, and how to properly install?
...
To your question - it wasn't too easy to fit them, I had to resort to tire levers in the end to get them on completely (both tires).
Eff me. So a top tire from an industry leading brand goes on nice and snug, everything else to spec and in good order, but the tire still blows off. What's a guy supposed to do? So much about this industry makes me wonder if we aren't guinea pigs for some company's beta project. Sticking with hooks - forever.
I know what you mean. For a while, was riding with Roval CLX50s which are tubeless compatible WITH hooks and still found that once the tires fall below a certain pressure like in a flat, the beads don't stay locked. This lack of a standard for wheels and tubeless tires to ensure they are safe as a system is ridiculous. Imagine if this persisted in the auto industry...

kervelo
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by kervelo

In my experience the tyre bead dropping from the rim shelf when empty is more related to some particular tyre brand. For example when the Schwalbe Pro One tyre is totally empty it quite often drops from the shelf of the Zipp 303S, but with the Continental 5000 S TR this does not happen. A tyre that has dropped from the shelf is much harder to inflate on the road, for example after plugging a puncture.

bobones
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by bobones

Conversely, I have wheels where GP 5000 S TR falls off the shelf when most other tyres don't. I think in my case it's because the Conti's are so damned tight. This happened to me when I got a cut that I had to plug, but fortunately the tyre reseated with a blast of CO2. I've got other wheels where it's been impossible to get the tyre unseated from the shelf by hand, and I've had to resort to levering them off with mole grips. That too spells disaster if you have to fit a tube on the road. Anyway, none of this is akin to a tyre blowing off a rim under pressure. Hookless just seems like a risk I can easily avoid.

joejack951
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by joejack951

Just curious, but as a possible outlier cause of an issue like this, have you checked the roundness of the wheel? If the wheel were an exaggerated egg-shape you could easily imagine a lack of proper tension across the narrow portion. If your wheel was say ~1mm out in radial true there would also be a lack of tension at that spot, but much less noticeable.

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Matt28NJ
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by Matt28NJ

If it were me, I'd remove the tire (marking the spot on the tire where it popped off the wheel just to be safe), clean everything up thoroughly and really examine the whole setup for any issues, including roundness, etc. Then contact Conti if warranted.

spdntrxi
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by spdntrxi

C36 wrote:
Thu Feb 09, 2023 11:16 am
The only Cadex wheel compatible with the GP5k s TR is the Cadex 42. Seems to be clearly stated in their website.
Edit: limit seems to be only for 25mm, not 28
if this is true... well this is the answer.
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stjepan
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by stjepan

spdntrxi wrote:
Wed Feb 22, 2023 6:12 pm
C36 wrote:
Thu Feb 09, 2023 11:16 am
The only Cadex wheel compatible with the GP5k s TR is the Cadex 42. Seems to be clearly stated in their website.
Edit: limit seems to be only for 25mm, not 28
if this is true... well this is the answer.
My tires are 28mm, they are compatible.

stjepan
Posts: 76
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by stjepan

joejack951 wrote:
Wed Feb 22, 2023 3:51 pm
Just curious, but as a possible outlier cause of an issue like this, have you checked the roundness of the wheel? If the wheel were an exaggerated egg-shape you could easily imagine a lack of proper tension across the narrow portion. If your wheel was say ~1mm out in radial true there would also be a lack of tension at that spot, but much less noticeable.
To my untrained eye the wheel seems to be fine and it is almost brand new (10 rides maybe in total).
The only logical explanation to me is that I didn't seat the tire properly around the valve so it managed to wiggle of there. That, or the tire is malfunctioning.
Didn't ride them again after the incident, but will give them a go in the coming days on an easy route and go from there.

AJS914
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by AJS914

stjepan wrote:
Thu Feb 09, 2023 9:13 am
warthog101 wrote:
Thu Feb 09, 2023 9:08 am
What pressure?
65 psi, so within range.
What is the range? I seem to recall 65psi being around the maximum for road hookless. I did google the AR 35 and can't find a single reference to max pressure.

It could also be that your tire gauge isn't accurate and you are on the edge of what is acceptable. Or this particular tire is defective (in diameter).

stjepan
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by stjepan

AJS914 wrote:
Wed Feb 22, 2023 7:26 pm
stjepan wrote:
Thu Feb 09, 2023 9:13 am
warthog101 wrote:
Thu Feb 09, 2023 9:08 am
What pressure?
65 psi, so within range.
What is the range? I seem to recall 65psi being around the maximum for road hookless. I did google the AR 35 and can't find a single reference to max pressure.

It could also be that your tire gauge isn't accurate and you are on the edge of what is acceptable. Or this particular tire is defective (in diameter).
73 psi is max pressure for hookless. It could be that the tire gauge isn't accurate, there's always that. I have a separate digital tire pressure checker, should employ it more often in the future.

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Mr.Gib
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by Mr.Gib

stjepan wrote:
Wed Feb 22, 2023 8:03 pm
73 psi is max pressure for hookless. It could be that the tire gauge isn't accurate, there's always that. I have a separate digital tire pressure checker, should employ it more often in the future.
Even if a pump is off by a few psi, or a gauge is inaccurate, surely there is adequate overhead beyond the max 73 psi as a safety margin for just this type of error? The tubeless and/or hookless tire/rim system is this idustry is still a bit of a mess. I don't know if it's bad design or bad manufacturing or a combination of both, but these blow-off events should not be happening.

I admit to getting more paranoid by the week even with my hooked wheelsets. What happens if a front tire blows off at 80 km/h on some snaking descent? Very small odds, but it is going to happen to someone.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

yinzerniner
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by yinzerniner

Mr.Gib wrote:
Thu Feb 23, 2023 10:06 pm
Even if a pump is off by a few psi, or a gauge is inaccurate, surely there is adequate overhead beyond the max 73 psi as a safety margin for just this type of error? The tubeless and/or hookless tire/rim system is this idustry is still a bit of a mess. I don't know if it's bad design or bad manufacturing or a combination of both, but these blow-off events should not be happening.

I admit to getting more paranoid by the week even with my hooked wheelsets. What happens if a front tire blows off at 80 km/h on some snaking descent? Very small odds, but it is going to happen to someone.
Read that the ISO testing for hookless rim/tire testing is 10% safety margin, which doesn't seem that safe at all. Hooked tubeless testing is somewhere in the region of 40-50% for redundancy
https://standards.iteh.ai/catalog/stand ... 775-2-2021
https://www.velonews.com/gear/technical ... pressures/

Enve and Giant supposedly do their testing a little differently and tell you which tires are compatible:
https://www.cadex-cycling.com/global/tire-test-protocol
https://www.enve.com/en/tire-compatibility/

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Mr.Gib
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by Mr.Gib

yinzerniner wrote:
Thu Feb 23, 2023 11:47 pm
Read that the ISO testing for hookless rim/tire testing is 10% safety margin...
That's a joke. Inflate in a cool room, ride in the hot sun - 10% is nothing. I have trouble imagining a group of ISO officials sitting around and deciding in good faith that 10% overhead should be fine for a product on which the users life depends. This just doesn't smell right. I wonder if there was some industry input on this.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

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