The ongoing hookless rims saga

[tristan]

From those images it's impossible to know whether the damaged rim is the cause or effect

[fa63]

If you have the Instagram app, you can zoom in on the image I linked to, and it is pretty clear the rim is broken right near the valve.

[fa63]

See to the left of the Zipp logo:

[glepore]

Your assuming it broke before the blowout, just as likely, maybe more that it fractured after. The times I've dinged carbon rims have been from hitting objects with an underinflated or almost flat tire.

[fa63]

Good point. I think there are way more questions than answers right now. Let's see if we get any straight answers; my guess is that we will get a lot of finger pointing instead from the various manufacturers.

[bikerboy337]

Sorry if this was already mentioned, but I’ve been following this thread for a bit now…..

Escape collective had a good podcast this week talking though hookless… and I generally agree with their final thoughts…. Hookless makes sense for off-road, wide tires at low pressure…. But for road applications with 29mm tires at higher pressure, I’m skeptical of the benefits and risks seem much higher of catastrophic failure than hooked tubeless…

Anyways the podcast was a good listen… worth checking out… I learned a few things and hookless has some standards that are not easy for the average consumer to figure out….

[RoosterCogset]

Originally Posted by fourflys

you kind of forgot to mention the very first note they have..

"Never exceed the maximum (MAX) tire pressure indicated on the rim, the tire or the rim tape."

Sure, but am speaking more about what they seemingly allow for their own Giant/Cadex system.

[fourflys]

Originally Posted by RoosterCogset

Sure, but am speaking more about what they seemingly allow for their own Giant/Cadex system.

the question I would have is what does the rim say? My CX2 rims on my Revolt has a sticker that says "do not inflate over 65psi", which should be fine for the intended applications on for that rim (gravel).. from the picture you posted, I have no idea of the intended use of that tire.. is it intended for use on hooked or hookless rims? regardless, you have to go with the lowest max of any system when combining things I think.. I won't lie, it would seem like a Giant tire and rim would be designed in unison with each other.. but, as I said, that tire might be intended to have use with more than just Giant rims..

*also, not sure of the age of that pic, but 28mm is not recommended for hookless anyway, as discussed in a couple other posts in the thread..

[Dave]

28mm is fine with hookless, if the rim isn't too wide. My 303s wheels were 23mm IW and optimized for 28mm, according to Zipp.

I'm not about to quit using my 28mm tires on my 25mm IW BTLOS rims, since the tire manufacturer says it's OK. I can let the air out and the tires are tough to unseat from rim, even after a year of use.

[Mark McM]

Originally Posted by fourflys

*also, not sure of the age of that pic, but 28mm is not recommended for hookless anyway, as discussed in a couple other posts in the thread..

Minimum tire width on hookless rims depends on rim inner width. 28mm tires are not recommended for rims with inner width of 25mm or more, but some Zipp wheels have 23mm inner width, and even the latest standards allow 28mm tires on these wheels. Enve has some hookless wheels with a 21mm inner width (such as the SES-2.3),and the latest standards allow 25mm tires on these wheels. Also note that ISO specifies a maximum of pressure of 500 kpa = 72.5 psi in 25mm tires, Enve actually recommends up to 90 psi in a 25mm tire on a 21mm inner width hookless rim. Which is just another example of confusion in the hookless rim market, which can lead to unintended results.

[Dave]

28 tires on 25mm IW hookless rims aren't recommended by ETRTO, but not everyone abides by ETRTO. They're just guidelines. Zipp claims to follow the guidelines, but their current tire compatibly chart still says 28mm tires are OK with 25mm IW hookless rims.

https://www.sram.com/en/zipp/campaig...-compatibility

[fourflys]

fair enough on the 28mm on certain IW.. as far as continuing to use 28mm tires based on what the tire manufacturer says, sure.. to each their own, but don't start blaming "hookless" when a tire comes off a rim and that rim has a different guideline that you didn't follow.. not saying this is any of the posters, just kind of what the spirit of the thread is about..

I'll just point out again that both of the pro riders pictured in this thread ride for the same team.. is the team following the lower pressure guidance on the rim or possible higher guidance on the tire, or neither and doing their own thing?

[rice rocket]

Pros also run prototype tires, so nothing on the sidewall actually matters.

[fourflys]

Originally Posted by rice rocket

Pros also run prototype tires, so nothing on the sidewall actually matters.

I guess my point is if someone is worried about the safety of a wheel/tire system, they should go with the lowest maximum pressure for either component.. pros are, of course, a different story as they are looking for, and can actually benefit from, marginal gains.. and are probably willing to take some chances to benefit from those marginal gains..

[MikeD]

About these Vittoria tire inserts, this claim is made on the Vittoria website:

In the event of a puncture, the Air-Liner road expands to fill the void, keeping the tire secure on the rim bead

Seems like this is a bogus claim (or maybe it works for hook beaded rims but not hookless).