Slowman wrote:
marcag wrote:
Slowman wrote:
thank you for the clarification. and for your participation in this thread. you're a good sport to indulge me.
you're absolutely right and i'll go further: whether i'm forking out $3000 or $300 i don't want to have to compromise. i'm glad you brought up optimization. i am routinely disappointed when i go to industry events and it's clear by the display that the brand folks in charge don't understand the features of the product(s) they make. i was heartened by the display in zipp's booth, where they're showing this new disc, because this BMC tri/TT bike is one case where the entire bike, from the frame to the wheel to the tire, is an optimized and fairly mature system. i think you can see how that is.
from disc brakes to tubeless to the whole wider tire thing i've always been at a disadvantage because i'm arguing in favor of the system when the system doesn't yet exist. disc brakes in tri bikes. questionable idea in 2016. until the system emerges that absorbs that tech.
so, i think we'll see a lot of 28c, which measure 30mm on average, on TT and tri bikes and they'll work now because all the new road bikes and most of the new tri bikes are optimized for this size, as are the wheels. this is why a tire of that size doesn't give up much if anything in aero, and wins big in Crr, handling, comfort. as for road, 25c is gone, even if some people don't know it yet. i think you see this in your own work with pro teams, yes? the working size in mass start racing is from 28c to 32c depending on road condition. this was inconceivable 2 years ago.
as to pressure what i'm hearing is that pro riders keep asking for wider rims, lower pressures, wider rims, lower pressures. but that's for this time of year. spring races. on the TT side, you would know more than i do. i don't find 5.8 bar scary or risky because i ride mostly zipp, cadex, enve and vittoria, schwalbe, cadex tires, goodyear, i trust all those combos to be safe at any pressure up to 85psi (notwithstanding the ETRTO's guidance of 72.5psi). if i was riding a different wheel or tire i might conclude differently. i personally don't ever feel a need in any of my riding, any use case, to exceed 65psi but it would be silly for me, where i sit, to lecture you on your business with your teams.
but there is one thing i would like to be clear on. there are tire brands i'm not listing above and i don't only avoid some of these brands for hookless, i avoid them for hooked. the safety issue isn't hooked or hookless. the safety issue is just the tire itself, regardless of the rim type.
And I thank you for not banning me for being a dick at times. The Canadian side of me is nice. The Frenchman side is argumentative.
Talking to the guy that was on hookless and believed he was leaving a bit on the table, they have been told, very clearly, 4.9max. Period, end of story. Now, will they bend the rules if they are off the podium by 10seconds on the last stage Monaco to Nice ?
You mentioned a bunch of brands there. One mechanic of a hookless team I was speaking to was responsible for making sure the pressure in the tires that go on the roof racks had .5 bar less in them because they were popping in the sun. His completely unscientific opinion was that it was tire related not wheel. He explained why, I can't disclose, but he really put suspicion in my head.
Here's a tough question : tomorrow morning I have to buy a disc. I will go 28, fine. I am a billionaire, money is not object (this is an imaginary situation). Why do I go with the hookless Zipp wheel where I may be borderline vs the HED hooked wheel where I have 0 to worry about ? If it was gravel, I don't care. Cobbles or casual road riding, I don't care. But I have a TT or Tri to do, why do I take the hookless wheel ? Maybe I'm too fixated on the 72.5. Which is strange because I always considered speed limits on the road as recommendations rather than rules.
on the tires: i am quite confident that none of the hookless wheels i ride for the road would lose a tire at anything remotely close to 5 bar. 7 bar then i'd begin to be concerned. otoh, a tire that would blow off at 6 bar on a zipp or cadex wheel, you're dreaming if you think that tire is safe on a hooked wheel. there are just unreliable tires, in my opinion, and i suspect this began with the move to road tubeless. the issue is the bead. bead stretch. but i'm not going to name specific tires or brands because it's just my opinion and i don't think it's fair to throw a brand under the bus without the kind of evidence i don't have.
on the disc wheel i'd buy tomorrow morning: i'm going to ride tubeless. so, discs that aren't tubeless optimized are disqualified. second thing, 28c tire. third, at least a 22mm inner bead width. i'm not riding 5 bar so zipp is not disqualified. whether i buy a zipp or a HED now falls to other considerations. is it aero? does it fit my budget? i would just go down the list of imperatives, disqualify discs that don't hit my thresholds, see what remains, probably buy the cheapest one.
I’d guess your personal hookless TLR list is similar to the list Enve posts for their wheels. Their list is from testing the tires on their wheels. They even recommend pressures higher than the new standards for some of the rim and tire combos. I assume these came from straight up testing.
The aspect of their list that stands out to me is how short it is. The other concerning aspect is the lack of the fastest rolling tires on their list.
Personally, I’m all in on tubeless for all my bikes besides the TT/Tri. I’m mostly all in on hookless for these bikes too, just because I’ve historically used Zipp and Enve brands due to warrranty and customer service. Some of this tubeless transition also came due to lack of recent racing for me. Like Trail posted previously, after years of balanced riding between TT and road/gravel bikes, I now find myself picking the road/gravel options due to the more comfortable TLR tires.
At the same time, I’ve had to keep my wife’s equipment updated for tri racing as she’s never stopped competing. When we updated her to a new bike, it was disc brake. So, new training and race wheels. She uses Zipp and all they offered last year for deep wheels was hookless. A lot of the concerns expressed in this thread aren’t an issue for her cuz she’s small and prolly lighter than all but the tiniest of Marcag’s UCI WT tested riders. Zipp is at 23mm internal for their deep race wheels (last year’s disc is 19mm internal).
The biggest bummer I noted when setting her up, was that Conti’s newest hookless compatible GP5000S TR and GP5000 TT tires in the 25mm width are not compatible with an internal rim width over 21mm. So, a 23mm internal width Zipp rim requires a 28mm or larger Conti tire. All of Conti’s tires larger than 25mm work with 25mm internal rim widths. This was a surprise to me. They skip over Zipp’s racing wheel standard of 23mm internal completely. Schwalbe is less conservative and does list their 25mm race rubber as 23mm internal rim width compatible. We’ve used these and in addition to rolling a little slower they proved less puncture resistant and don’t seal well so they are no longer an option.
