terrymorse 

"Actually"?

Based on the number of posters asking for advice, because their tire always unseats upon deflation, I suspect the tubeless tire unseating problem is a bit more common than extremely rare.

I also wouldn't consider a tire bead coming off its rim hook and dropping into the rim valley "catastrophic". I'd call that "getting a puncture".

Atlas Shrugged

Again I am speaking from experience and you are repeating hearsay. As mentioned it is extremely rare to have such a catastrophic puncture as to lose all the air in a tubeless system, as well as unseat the bead, which is also very rare after a tires has been mounted and seated for a while.

No point in reengaging in the thousandth post litigating tubeless tech. Let the market speak for itself, the performance and sporting end of cycling has selected tubeless. This BF is the cycling equivalent of a remote South Pacific Island where a Japanese soldier is holding out still believing in Japanese superiority and the Emperor. Almost every topic discussing an issue devolves into how anything developed since the 80’s is flawed crap.

terrymorse 

You have share a single user anecdote, the "here-say [sic]" posted on the internets are multiple anecdotes.

The plural of anecdote is "data".

PeteHski

IME whenever I deflate tubeless tyres for removal they remain seated and you have to push them quite hard to break the seal. Maybe this is more of an issue with hookless rims or certain tyre/rim combinations. It would be an issue if it happened but I’ve been running tubeless mtb for 20+ years and road tubeless for 4 years and never experienced this issue.

t2p

this actually did happen

not a catastrophic failure - just a regular flat

the rider (a friend) was unaware he flatted and continued to ride - and the tire unseated

not a big deal - tube inserted and continued the ride - and not enough to convince him to ditch tubeless

PeteHski

That makes sense now thanks.

terrymorse 

Yeah, that was the type of thing I was thinking of that would unseat a tire: rolling while fully deflated.

I've gotten a few rapid deflations from large punctures while riding clinchers, so I continue rolling straight and brake gently. That several seconds of rolling drops the tire off the rim hook, where it can still be ridden safely. Unless the tire fits really loosely (modern tires like GP5000 are tight), it's not going to come off the rim.

A rapid deflator from last October:


GP5000 vs drywall screw

squirtdad

just for fun and to educate my self, I compared weight starting with the OP stated wheel set weights and using Vittoria Corsa Pro tubeless and tubular tire weights for 28 mm (2 tubeless and 3 tubular), adding 60 grams for sealant in 2 tires for the tuble (might be low but 30 ml per tire is what i used in tubed) and 26 grams for dyna plug kit, (and assume same pump,co2 etc setup)


I got 1700 gram for the tubeless and 1760 for tubular so 60 grams more with a spare for tubular. All said and done not significant for mere mortals (60 grams is a 1/6 cup of water)

of course this will vary between tire, rim and hub choice

I am glad I am not much of a weight weenie.....I weigh too much and am focusing on a) increasing fitness and b) weighing less. For me pushing it is 32 spoke mavic 330 tubular rims

Maelochs

The whole deal here is that while making a high-speed descent if a tire fails, because of the higher forces involved the chances of the tire unseating are higher .... even a lowish-speed downhill corner will possibly pull a tire off before the rider can safely brake to a stop (he said ruefully, picking up his bike, his bottles, his lights, and his scraped, bruised, battered, bleeding body.)

In other words, experience has taught me that any sort of clincher tire, tubed or tubeless will come off the rim if you keep rising it ... and yes, the tire will for a while ride half on the rim, which makes handling very sketchy, but in my experiences I have not been able to keep on riding safely on a deflated clincher. It has always either dumped my by sliding back and forth, (so that I am balancing on a rim edge, and alternating between rim edges, with one rim edge atop a sliding rubber cushion) or has come off and jammed in the brake or fork.

I have never ridden tubulars, but I would bet coming downhill at speed, a rider would feel just as unsafe because the tubular would grip the road while the rim would shift side to side .... but it might be safer for the amount of time needed to get the bike safely stopped. Not intending to perform that test.

And pretty much none of that has to do with WHEEL failure.

if the thread were titled "Is descending on anything but tubulars worth the risk," well, that is not this thread.

So if the OP deems either wheelset to be safe enough regardless of which tire style it uses .... then we are back to choosing which wheel based on other criteria.

Dave Mayer

Tubular vs. Clincher weight comparison

Tubular:

Shimano C24 wheelset: 1,110g actual
Tires Continental Competition 25s 280g x 2 = 560g
Total: 1,670 g

Clincher:

Shimano C24 clincher wheelset: 1,421g actual.
Tires Continental GP5000 25s 215g x 2 = 430g
Rim strips?
Butyl tubes 100g x 2 = 200g
Total: 2,051 g

Difference: close to 400g or most of a pound.

Don't add a spare tubular, this is an unfair comparison. If you add sealant to the tubular tires, they are just as puncture resistant as tubeless with sealant. But with tubulars, you do not have to add sealant. With tubeless, you do.

And the Conti tubulars have butyl tubes, not latex tubes that you have to reinflate every few days. Compare like for like.

Almost a pound of rotating mass? Huge difference.

Can you get a rim brake option with tubeless? If no add another 110g per wheel (each rotor) of unnecessarily ballast.

urbanknight

I have always LOVED the ride quality of tubulars, but they're just not practical for everyday unsupported rides. Even when I raced, I only used the tubulars during a race when there was a wheel pit or support vehicle nearby and ran clinchers while training (ok always tubulars on the velodrome, but that's irrelevant here). I even explored running tubulars with sealant in them, but realized even then you can't just throw a tube in one to get you home like you can with a tubeless tire.

Unless you have mobile support on your rides, or want a second pair you only use on rides that have roaming support, stick with tubeless.

urbanknight

Not sure if I understand your reasoning. Technically, you don't have to add sealant to either kind. Without sealant, tubulars or tubeless will run just fine until you get a puncture, then they go flat. The difference is that you would throw a spare tube in the tubeless tire while you would throw on (and glue) a spare tire for the tubular. If you run sealant in both, they will both likely seal a puncture about the same, and once again the difference is as I stated previously if you get a cut larger than the sealant or plug can fix.

tomato coupe

No. Physics says otherwise.

PeteHski

The OP is comparing tubeless vs tubular on 2 specific wheelsets. Not that it really matters.

t2p

even 20 years ago tubulars were being pushed by the top clinchers

BITD / 90’s - only a few guys in our road group rode tubulars (‘sew ups’) - and just on select bikes (not all of their bikes)

their thoughts : the top tubulars were very good / great ride etc - but below that level the tubulars were around equal to a good clincher and maybe performed below that level

in their opinion - too many were comparing the performance of a top level tubular tire to a mid level clincher (and few actually used the top level tubulars)

at that time - good portion of the group were riding Michelin (Hi Lite Comps and Super Comp HDs - later Axial Pros) … Vittoria (Open CX ? can’t recall model) … Conti GP’s …

Koyote

It’ll get the OP up a 30km climb at a constant 7% grade about a minute faster — in three hours 18 minutes instead of three hours 19 minutes.

Huge.

Bike Calculator

PeteHski

That's cool, so nothing in it really. I'm not much of a weight weenie either. I think my wheelset is around 1500g ish on a sub 8 kg bike. Not super light, but not heavy enough to bother me on big mountain climbs. For me 1 kg of weight is worth about 45 sec per hour of pure climbing and next to nothing everywhere else.

Trakhak

My Chromebook says that's not a secure connection. Does that 1-minute reduction in elapsed time simply represent a difference of a pound in overall bike weights or is rotating weight factored in?

Koyote

Doesn’t matter, since the difference is trivial.

(The physics on this has been done to death… But I expect that won’t end the internet debate.)

rosefarts

The huge advantage of going full weight weenie is mental. Seems irrelevant but it totally matters.

It’s the same thing as a fresh new haircut gives you more confidence or how you can ride faster on your birthday. It shouldn’t matter but it does.

When we plug weights into a calculator, that’s not the whole picture. The guy who picks up his bike and it feels like it’s made from pixie dust gets that extra edge. It’s real.

Whether that “feelin fancy” threshold is for a 1600, 1100, or 750g wheelset is up to the person.

We’re organic and emotional lumps of meat rolling around. Not machines. Hard to quantify but we can’t ignore the effect either.

Atlas Shrugged

His basic calculation was flawed, he neglected to include a spare. Assuming that sealant works inside a tubular tire works the same as a tubeless, which is incorrect. Sealant does not work very well inside of a tubular tire and anyone who has tried it knows this.

tomato coupe

ftfy

bruce19

I have 4 road bikes and a cross bike. My wife has two road bikes and a cross bike. Five years ago I converted all bikes to tubeless from clincher. The only experience I can add is that we have had zero flats or problems.

Koyote

And plugs don’t work at all in a tubular tire.


Oh, it’s mental. For sure.

Atlas Shrugged

What do you know! My friend told me about someone he road with once that had a tire that was hard to mount and had a slow leak proving tubeless is just a marketing scam imposed on the sheep cyclists by big bike.