Slowman wrote:
rruff wrote:
Slowman wrote:
i'm getting the sense that road tubeless is like disc brake: nobody's going to ask your opinion or mine; this is where the industry is going.It's going there really slowly.... Really, how much progress has it made lately?
It didn't take long for tubeless to dominate MTB. On road bikes the only benefit shows up if you run over goatheads regularly. Even then a latex tube will usually not puncture, IME.
i think gravel is the key. tubeless is taking over gravel as well, which will bring tubeless down to 33mm or 35mm and by then you're pretty much a skip away from road.
The thing is...practically speaking, that "skip" is quite large. And, it's mostly that large due to the differing use cases and dominant failure modes between gravel/MTBs and road cycling.
Think of it this way: Why did tubeless get adopted so quickly in MTBs, yet seems to be struggling to gain a hold in road cycling? What problem did the technology solve in MTBs? And, is that same problem also a major driver in road applications?
In a recent CyclingTips podcast on this subject, Caley Fretz summed it up quite clearly, in that THE major problem that tubeless technology solved for MTBs is pinch-flatting. Pinch-flatting in cycling applications on rough/rocky surfaces is a much bigger problem than punctures. I can attest to that myself in my own long-term MTB use. The tubeless technology immediately allowed MTBers to run much lower pressures than they would be able to with tubes (without fear of pinch-flatting), and they gained the traction, control, AND rolling resistance advantages of that lower pressure. That's a win...and it's no mystery that people were quick to move to it. Heck, even I experimented with DIY tubeless on my MTB before the manufacturers got on board and figured things out. That type of clamoring hasn't existed in the road biking realm.
The desire for tubeless in "gravel" is much the same...as I've said before, these bikes are really just vastly improved rigid MTBs with drop bars ;-) Pinch flat protection is the main desire in that use case as well.
Now then...let's look at tubeless for road applications. Here, arguably the higher failure mode is punctures. Pinch flats are a far lesser concern (even more so when running latex tubes). This is where the technology falls short, in that the sealants can't really handle plugging all but the smallest holes, and not without a fairly large loss of pressure (due to the much lower air volumes as compared to MTB/gravel tires), and usually not without a large mess or needing to stop and "fiddle" with the wheel anyway. That's been my experience with using road tubeless. Now then, I don't live in a place where goatheads are prevalent...but, if I did, I'm sure I'd be more excited about dealing with the road tubeless downsides to better deal with that. But, like most road users...I don't live in that territory.
So...once again, people are projecting that a certain technology is the "best" for all use cases due to it being appropriate for particular use cases. The problem is, the conditions and failure mode rates are different, and so that's not necessarily the case.
Slowman wrote:
what are the advantages? here's what i'd say, theoretically, at least:
1. lower Crr - Not really. A latex tube doesn't add any measurable Crr vs. a tubeless tire at road pressures. "Theoretically", why would you expect tubeless to be able to have lower Crr?
2. no flats - "No"? Hmmm...then why does anyone worry about being able to break a bead to swap in a tube? Or, carry plug kits?
3. if you do get a flat, plug it - Yes. But, even some flats (e.g. sidewall cuts) may require a boot and tube anyway, which can be made doubly hard by dealing with a non-stretchable tubeless bead.
4. no leakdown (remember, you'll need latex tubes to match tubeless performance) - "No"? Sure, it's slower...but is leakdown of latex tubes really a problem? My experience says no.
5. 1 product instead of 2 (no tube needed) - Actually, same part count. The tubeless setup still needs a valve. On tubed setups, it happens to be attached to the tube ;-)
6. for manufacturers, it means the chinese will have to catch up to a new standard - They'll just copy it to various levels of success, as has happened in the past...and then sell it for much less.
Slowman wrote:
on that last part, you might think that's easy, but it's going to take the chinese some time to catch up to the precision required for a tubeless. rim and matching tire. esp if there is any IP to protect western wheel makers. - I have a feeling that trying to enforce IP in this product space is not going to help speed up adoption.Slowman wrote:
and then finally, who is investing in tubed gravel tires and wheels right now?Ummm...seems to me that "tubeless" gravel tires and wheels are ALSO tube-capable, no?
Slowman wrote:
at least that's my guess. i believe i was the lone voice in the wilderness 3 years ago in my disc brake in tri prognostication. so, do you feel lucky? do ya, punk. ;-)
What exactly was your prognostication? That they'd exist?...They certainly haven't been quickly adopted. Merely existing wasn't much of a stretch, seeing as how they existed back then already ;-)
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