Wheels, Tires, Tubes, Tubeless, Tubs, Spokes, Hookless, Hubs, and more!
Moderator: robbosmans
Forum rules
The spirit of this board is to compile and organize wheels and tires related discussions.
If a new wheel tech is released, (say for example, TPU tubes, a brand new tire, or a new rim standard), feel free to start the discussion in the popular "Road". Your topic will eventually be moved here!
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aeroisnteverything
- Posts: 897
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by aeroisnteverything on Thu May 12, 2022 3:33 pm
blaugrana wrote: ↑Wed May 11, 2022 12:30 pm
pmprego wrote: ↑Wed May 11, 2022 11:05 am
I've now read the cycling tips article. Besides the marketing bulshit, I "love" how specialized felt the need for, after screwing up their own customers, putting a phrase out screwing up all other wheels manufacturers: "Wehan wouldn’t explicitly outline the findings, but he said Roval did test some other makes and models of tubeless-compatible carbon road wheels with seemingly mixed results."
In spesh decision room was something like: let's put something out that will leave a big mantle of doubt/suspicious over all other brands and that way diverging the attention from our own screw-up to others.
Yes, this is quite oportunistic. Maybe only some random Aliexpress wheels failed, maybe most of the pricey high end ones did. We don't know which manufacturers release tubeless wheels without testing them tubeless, but just because they almost did with these wheels (and apparently did with everything released before, they just got lucky), it's unfair to group all the other manufacturers together.
Yeah, agree with all that. The whole thing is a bit nuts. The way Sagan incident happen - I don't know how you design a wheel to withstand it. Like, what's the test protocol that is sensible under the circumstances? I think I have a pretty firm expectation that if I impact a 20 cm curb head on at 50kph either a wheel will break or the fork/steerer will break, or both. I am also going to fall pretty badly at that speed over the handlebars and probably break a bone or two. If I impact it at 5 kph, nothing particularly unpleasant should happen. A What is the curb impact speed at which a wheel should maintain integrity and survive the impact? I dunno, honestly. I am also not sure why it is that tubeless vs non tubeless would perform differently here. If a crash results in a rim bed failure from the impact in a wheel with an inner tube, the chances of the tube and tyre coming off are very high. Maybe the sides of the rim don't crack, but that give me very little comfort. A lot of obfuscation by Specialized and lots of useful information that is being withheld for the users of gen 1 Roval Rapide wheels (whether used with or without an inner tube).
In any case, I feel like wheel (and frame) makers should publish their impact test protocols so we can draw somewhat informed conclusions about the kinds of abuses that wheels can withstand, rather than just guess like we currently do.
Then from reading the roadbikeaction article, I get the impression that I need to add another layer of tubeless tape onto the rovals to prevent the sort of failure where the air goes into the rim cavity. Tubeless tape would seem to me to be identical or better than an inner tube for this purpose.
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pmprego
- Posts: 2535
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by pmprego on Thu May 12, 2022 4:33 pm
aeroisnteverything wrote: ↑Thu May 12, 2022 3:33 pm
Then from reading the roadbikeaction article, I get the impression that I need to add another layer of tubeless tape onto the rovals to prevent the sort of failure where the air goes into the rim cavity. Tubeless tape would seem to me to be identical or better than an inner tube for this purpose.
I guess both rapide and alpinist have the escape hole on the rim.
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cat4forlife
- Posts: 87
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by cat4forlife on Fri May 13, 2022 9:06 pm
aeroisnteverything wrote: ↑Thu May 12, 2022 3:33 pm
Yeah, agree with all that. The whole thing is a bit nuts. The way Sagan incident happen - I don't know how you design a wheel to withstand it. Like, what's the test protocol that is sensible under the circumstances? I think I have a pretty firm expectation that if I impact a 20 cm curb head on at 50kph either a wheel will break or the fork/steerer will break, or both. I am also going to fall pretty badly at that speed over the handlebars and probably break a bone or two. If I impact it at 5 kph, nothing particularly unpleasant should happen. A What is the curb impact speed at which a wheel should maintain integrity and survive the impact? I dunno, honestly. I am also not sure why it is that tubeless vs non tubeless would perform differently here. If a crash results in a rim bed failure from the impact in a wheel with an inner tube, the chances of the tube and tyre coming off are very high. Maybe the sides of the rim don't crack, but that give me very little comfort. A lot of obfuscation by Specialized and lots of useful information that is being withheld for the users of gen 1 Roval Rapide wheels (whether used with or without an inner tube).
The risk of such a failure must have been high enough for Specialized to pull the plug on selling these rims as tubeless compatible. Just think about it. Specialized had spent a few years designing and testing these rims - unfortunately not impact-tested while tubeless - and had invested a ton of money to get ready to sell these as tubeless compatible, and only in the last moment realized they could not be sold as tubeless compatible. Perhaps these rims should have never been sold in the first place but Specialized made what i guess is a financial decision to sell them as tube-only, may be to recoup their investment. No credit to them for the marketing BS that these rims were faster with tubes and for not revealing the reason until now, but i should at least give them credit for warning users that such rims were not tubeless compatible.
If you want to run these version 1 rims as tubeless, you run them at your own risk. For me, it is irresponsible for a business to set up and sell these rims as tubeless compatible, without informing the customers Specialized's revelation why such rims should not be run tubeless.
aeroisnteverything wrote: ↑Thu May 12, 2022 3:33 pm
Then from reading the roadbikeaction article, I get the impression that I need to add another layer of tubeless tape onto the rovals to prevent the sort of failure where the air goes into the rim cavity. Tubeless tape would seem to me to be identical or better than an inner tube for this purpose.
Another layer of tubeless rim tape would not have prevented the Sagan failure. Enve's pressure relief valve stem nut is designed to prevent the kind of failure where the air goes into the rim cavity, but again, it would not have addressed the Sagan failure. It's a seprate issue.
https://www.enve.com/journal/behind-the ... -stem-nut/
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aeroisnteverything
- Posts: 897
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by aeroisnteverything on Sun May 15, 2022 8:04 pm
cat4forlife wrote: ↑Fri May 13, 2022 9:06 pm
...
Another layer of tubeless rim tape would not have prevented the Sagan failure. Enve's pressure relief valve stem nut is designed to prevent the kind of failure where the air goes into the rim cavity, but again, it would not have addressed the Sagan failure. It's a seprate issue.
https://www.enve.com/journal/behind-the ... -stem-nut/
I hear all that but am quite confused in what way the presence of an inner tube in that incident would have made things better. Inner tubes would pinch flat instantly when a wheel tyre hits a curb like that. Then what? Does the tubeless tape and rim bed not fail in the same way as it did when Sagan crashed? If there is a different failure mode with the tubes in, what is it?
Also, let's not forget, Roval specs these for weight limit of 125kg. That's heavy, when it comes to impact testing, for such a lightweight rim!
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gSporco
- Posts: 949
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by gSporco on Mon May 16, 2022 4:47 pm
aeroisnteverything wrote: ↑Sun May 15, 2022 8:04 pm
cat4forlife wrote: ↑Fri May 13, 2022 9:06 pm
...
Another layer of tubeless rim tape would not have prevented the Sagan failure. Enve's pressure relief valve stem nut is designed to prevent the kind of failure where the air goes into the rim cavity, but again, it would not have addressed the Sagan failure. It's a seprate issue.
https://www.enve.com/journal/behind-the ... -stem-nut/
I hear all that but am quite confused in what way the presence of an inner tube in that incident would have made things better. Inner tubes would pinch flat instantly when a wheel tyre hits a curb like that. Then what? Does the tubeless tape and rim bed not fail in the same way as it did when Sagan crashed? If there is a different failure mode with the tubes in, what is it?
Also, let's not forget, Roval specs these for weight limit of 125kg. That's heavy, when it comes to impact testing, for such a lightweight rim!
Presumably, inner tubes would make them better because you would have to run them at higher pressures. Higher pressures reduce pinch flats.. Again, assuming here that they probably tested tubeless at say 60-70psi and tubed at 75-95psi.. The tubed at that pressure would bounce of most objects or just pinch flat and not smash the rim.. The tubeless would deform until it couldnt then the rim is taking the brunt of blow. Thats my guess.
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yinzerniner
- Posts: 220
- Joined: Tue Jun 13, 2017 8:54 pm
by yinzerniner on Mon May 16, 2022 5:45 pm
gSporco wrote: ↑Mon May 16, 2022 4:47 pm
aeroisnteverything wrote: ↑Sun May 15, 2022 8:04 pm
cat4forlife wrote: ↑Fri May 13, 2022 9:06 pm
...
Another layer of tubeless rim tape would not have prevented the Sagan failure. Enve's pressure relief valve stem nut is designed to prevent the kind of failure where the air goes into the rim cavity, but again, it would not have addressed the Sagan failure. It's a seprate issue.
https://www.enve.com/journal/behind-the ... -stem-nut/
I hear all that but am quite confused in what way the presence of an inner tube in that incident would have made things better. Inner tubes would pinch flat instantly when a wheel tyre hits a curb like that. Then what? Does the tubeless tape and rim bed not fail in the same way as it did when Sagan crashed? If there is a different failure mode with the tubes in, what is it?
Also, let's not forget, Roval specs these for weight limit of 125kg. That's heavy, when it comes to impact testing, for such a lightweight rim!
Presumably, inner tubes would make them better because you would have to run them at higher pressures. Higher pressures reduce pinch flats.. Again, assuming here that they probably tested tubeless at say 60-70psi and tubed at 75-95psi.. The tubed at that pressure would bounce of most objects or just pinch flat and not smash the rim.. The tubeless would deform until it couldnt then the rim is taking the brunt of blow. Thats my guess.
Pinch flatting and higher pressure with tubes has nothing to do with why tubes would have prevented and/or lessened the destructive rim breakage in the Sagan curb impact event, or one like it.
It's rather that the tube acts as an air modulater in the event of a rim cracking due to the impact. So in a system with a tube a big impact will crack the rim and cut the tube, but the air will still need to escape the tube at the puncture point before it can then be released into the rim cavity through the crack/hole. With a tubeless setup the the impact will crack the rim but the air will release directly into the rim cavity through the larger crack/hole, and that rush of air is what also caused the rim failure in the Spesh tests, according to them.
From the Cyclingtips article:
https://cyclingtips.com/2022/05/roval-r ... -tubeless/
“You could crack the rim, and just having the tube, that little bit of extra material, slows the air down enough and distributes the force just enough,” explained Roval wheel category leader Chris Wehan. “So instead of that force trying to push that crack apart, the air goes somewhere else and dissipates.”
Just think about trying to seat a tubeless tire with a valve core in vs a valve core out - the valve core in is like the tubed scenario since the aire needs to get past the core and the smaller hole before it can expand out towards the tire, and the flow of air and subsequent outward force is reduced. Whereas if you remove the valve core the flow/volume of air is much higher and thus has a greater force to push the tire out/up for seating.
That is, if you believe Specialized's word.
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FlatlandClimber
- Posts: 2491
- Joined: Tue Mar 31, 2020 3:37 pm
by FlatlandClimber on Sat May 21, 2022 2:02 pm
Front yes, rear no.
Cervelo P5 Disc (2021) 9.1kg
Factor Ostro Gravel (2023) 8.0kg
S-Works SL8 (2023) 6.3kg
*weights are race ready, size 58/L.
Sold: Venge, S5 Disc, Roubaix Team, Open WI.DE, Émonda, Shiv TT, Crux, Aethos, SL7
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Sace
- Posts: 40
- Joined: Thu Dec 31, 2020 12:26 pm
by Sace on Sat May 21, 2022 7:48 pm
ryanw wrote: ↑Tue May 10, 2022 6:58 pm
Just buy the first gen. Save weight, money and still 1,000,000,000% tubeless.
Is the Roval tape in the first gen TLR or do you retape them?
I'm tempted to convert my Rapide CL's
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ryanw
- in the industry
- Posts: 2284
- Joined: Sat Apr 16, 2016 6:52 pm
- Location: London
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K4m1k4z3
- Posts: 350
- Joined: Sun Nov 05, 2017 1:33 pm
by K4m1k4z3 on Tue May 24, 2022 8:40 am
To those who have purchased 1st gen Rapide CLX: Could you please share the included tension charts that come with the wheelset? I'm especially interested in the 24H rear wheel. Thanks!
'24 S-Works Tarmac SL8 RTP - soon™
'22 Tarmac SL7 Expert | Ultegra R8100 | Alpinist CL / Custom Rapide CLX 2x60
'19 Diverge E5 Comp
'18 Epic HT Comp Carbon WMN
'18 TCR Adv Pro 1 Disc
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bob78h
- Posts: 18
- Joined: Sun Oct 24, 2021 7:30 am
by bob78h on Wed Jun 01, 2022 2:21 am
A little off topic but anyone know anything about the new Specialized tubeless tires? The pros are clearly on something new with a grey logo, assuming a new Turbo Cotton or replacement for the RapidAirs. Was expecting they would announce them with the new version of the Rovals (here's our new wheels that are tubeless compatible and only with this new tire), but they didn't.
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gSporco
- Posts: 949
- Joined: Mon Jul 13, 2020 4:58 am
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Contact:
by gSporco on Wed Jun 01, 2022 6:35 am
bob78h wrote: ↑Wed Jun 01, 2022 2:21 am
A little off topic but anyone know anything about the new Specialized tubeless tires? The pros are clearly on something new with a grey logo, assuming a new Turbo Cotton or replacement for the RapidAirs. Was expecting they would announce them with the new version of the Rovals (here's our new wheels that are tubeless compatible and only with this new tire), but they didn't.
Specialized will release the new Roubaix and Turbo tubeless once they have adequate stock to ship
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chrhag
- Posts: 24
- Joined: Fri Nov 27, 2020 5:49 pm
by chrhag on Fri Jun 03, 2022 1:16 pm
gSporco wrote: ↑Wed Jun 01, 2022 6:35 am
bob78h wrote: ↑Wed Jun 01, 2022 2:21 am
A little off topic but anyone know anything about the new Specialized tubeless tires? The pros are clearly on something new with a grey logo, assuming a new Turbo Cotton or replacement for the RapidAirs. Was expecting they would announce them with the new version of the Rovals (here's our new wheels that are tubeless compatible and only with this new tire), but they didn't.
Specialized will release the new Roubaix and Turbo tubeless once they have adequate stock to ship
Fingers crossed that they'll get released before I receive the new CLX II