There seems to be very few UST-tubeless clincher tyres out there. Is it possible to use a new standard clincher tyre and set it up as tubeless?

why would you want to? Unless you’re getting endless punctures the benefits are not as clear cut on road bikes. Lots of faff for not a lot of benefit. IMO

To answer the question, no, you can’t. It will blow off the rim.
You need to use tubeless ready tyres like the Bontrager TLR, Schwalbe The One tubeless or Hutchinson.

No, the sort of pressures road tyres need will blow a non-tubeless road tyre off the rim. The bead just won’t be strong enough.

the sort of pressures road tyres need will blow a non-tubeless road tyre off the rim

Everyone says this but has anyone actually seen it happen?
How does a tyre know whether it has a tube in it or not?
The force exerted on a tyre by a tube at a given pressure will be the same as it would be with no tube….. or am I missing something…?

I can understand a tyre not sealing very high pressures perhaps; but why would it blow off the rim?

Would only use tubeless ready on the road bike, they do seem to have a lot tighter beads and more substantial carcasses. Not that a normal tyre would blow off the rim but if there is a loss of air before sealed by the sealant would have a much greater impact on pressures than a more volume mtb tyre therefore could easily roll off the rim. Causing face Tarmac issues..
For me there is a huge difference riding tubeless on the road, close to tubs feel but a lot less hassle.

I personally wouldn’t try it.
Tubeless is the way to go, I’ve just fitted Schwalbe The One, the difference is amazing, rolls so much easier and quicker.

I’m not sure the tyre will blow off the rim. It might not seal though due to the presure. Try it.

The issue I have heard with road tubeless is that due to the high presure the sealant is forced through the puncture hole for a few secs before it seals leaving you and the bike covered in it. Changing a puncture is therefore easier than cleaning you and your bike.

I have tubless ready road rims and run tubes.

I personally wouldn’t.
Recently fitted Schwalbe the one tubeless, the difference is amazing – rolls so much easier and quicker. Ridden in quite awful conditions as well, no punctures or air loss. The way to go.

Everyone says this but has anyone actually seen it happen?
How does a tyre know whether it has a tube in it or not?
The force exerted on a tyre by a tube at a given pressure will be the same as it would be with no tube….. or am I missing something…?

No, because after putting 50psi in a 2″ MTB tyre (i.e. the same force as a 100psi 1″ road tyre) I’m not stupid enough to do it again. And that was with a tubeless ready tyre on a stans rim.

It’s to do with the stretchyness of the bead and how tightly it fits under the hook. The Tube provides enough force to keep the bead under the hook even as it stretches. Without the tube the bead can stretch and lift up past the bead hook and BOOOOOOOOMMMMMMMM you have a ‘badger incident’ only much louder.

Errrr. Not sure how 50psi is the same as 100psi . The footprint pressure exerted onto the road might be the same, but the internal pressure of the rubber / spoke bed isnt.
more info needed. linky link for the hard of learning please.

I would NOT try to run a non-tubeless road tyre as a tubeless set up.

I’ve had a mountain bike tyre blow off a rim in my face whilst trying to get it to seat tubeless at 60psi. It was like a bomb going off. Ringing in the ears, temporary deafness until the real world around comes back to the senses. Sealant everywhere and a tyre with a strange deformed sidewall were the more trivial lasting evidence.

Not a good experience.

I wouldn’t try it. Singletrackmind, I wouldn’t care about the physics if I were you, just learn fron the mistakes of others so you don’t have to 😉

that was loud

blow off

Errrr. Not sure how 50psi is the same as 100psi .

Because for a 1″ section of bead (as pressure is in lb/inch2 and width is 1″ for a 25mm tyre and 2″ for a MTB tyre)

50 lb/inch2 x 2″ width = 100lb per inch circumference force pulling the bead off the rim

100lb/inch2 x 1″ width = 100lb per inch circumference force pulling the bead off the rim

And if you don’t believe me and think 100psi puts the same force on the bead regardless of the tyre, go try putting 100psi in your MTB tyres and see what happens.

or just get latex inner tubes and use whatever tyres you want and whatever pressures work for you

why would you want to? Unless you’re getting endless punctures the benefits are not as clear cut on road bikes. Lots of faff for not a lot of benefit. IMO

Having ridden tubeless on the road for about 8 months now, I couldn’t disagree more. Tubeless on road makes as much sense as it does offroad to me!

You CANNOT run non tubeless road tyres in a tubeless setup. The beads of a Tubeless tyre are massively stronger and stiffer than a conventional road clincher tyre. I’m running Tubeless Schwalbe One’s on my carbon road bike and they’ve been totally amazing, I just wish that Schwalbe did a Tubeless Durano too for the winter months!

TINAS I don’t think your maths is right. I don’t see how how the width of the tyre has anything yo do with the force exerted at its bead by the pressure within it. Also you are not accounting for what angle the sidewall of the tyre makes with the sidewall of the rim.

I got a non UST/TLR tyre to seat fine on my Alphas, was put off riding it by the fear/hype. I’ve not seen any convincing explanation as to why the bead in a regular tyre is stretchy enough to blow off without a tube (which is by comparison infinitely stretchy!) “holding” it in place / how a UST/TLR bead is so much less stretchy – people (such as mboy) presents it as fact – but no one explains it.

Al, you work in a shop, take a tubeless and non tubeless version of the same tyre off the shelf and inspect them both. The bulk of the extra material on the tubeless tyre is in the bead. Also, the tubeless tyre will be ever so slightly a tighter fit on a rim too, just like MTB tubeless tyres are.

If you’ve got to be the one that has to find out everything for yourself, then please, go ahead, knock yourself out (quite possibly literally if you’re putting 100psi into normal road tyres with no tubes in!), but don’t say we didn’t warn you…

FWIW have chatted at length with with the Schwalbe Rep about the how’s and the whys of tubeless road tyres. I’m prepared to heed their advice and warnings on the matter to be fair!

the sort of pressures road tyres need will blow a non-tubeless road tyre off the rim
Everyone says this but has anyone actually seen it happen?

When I built my new road wheels with Stans Alpha rims I fitted some Michelin Pro3 tyres without realising that I needed tubeless specific tyres too. Certainly made a loud bang when at about 90 psi, a bit of a surprise in the living room 😀

So yes, certainly need expensive tubeless tyres with non-stretchy carbon bead.

Cheers, Rich

Do you really need to run tubeless or are you just following the hype?

C’mon, you ride in lanes covered in grit and crap and water run off from fields, you’re hoping tubeless will “make your ride come alive” whilst not actually thinking about where/when and how you ride your bike. It’s just a diversion tactic, when really all you need to do over the winter is stick some decent tyres on your roadie, pump them up a bit more than you have been doing and go ride the thing until you puke. Take a spare tube and some patches too for those annoying, and not very often, punctures that add about 15mins to your playtime should you get a puncture.

You should be more concerned about how you ride that roadie of yours than looking for some kinda diversion that puts you off riding it.

Clearly IMO 😉

I have been running Michelin pro 4 tubeless. No issues with blowing off but they were a tight fit (and still are). Main problem is porous sidewalls which don’t seem to seal over time like they would on MTB. Also need extra layer of tape on rim (learnt this the hard way).

As above, advantages seem less clear cut than mtb.

If you’ve got to be the one that has to find out everything for yourself,

Im not going to try it at all- but for a different reason. I just like to understand stuff properly.
The reason I wont be trying it is because the volume of the tyre is too small. It wont take very long for any tiny leaks to deflate the tyre enough for it to drop off the rim; also there is hardly any room for sealant.

…but Im still not buying the whole exploding off the rim thing – at least not as a result of pressure; and I won’t until someone can give me a proper explanation (one that isn’t to do with floppy beads that hold up perfectly well with an inner tube)

TINAS I don’t think your maths is right. I don’t see how how the width of the tyre has anything yo do with the force exerted at its bead by the pressure within it. Also you are not accounting for what angle the sidewall of the tyre makes with the sidewall of the rim.

It’s a simplified version of the calculation as I’d use for working out the thickness requirements for pressure vessels on a refinery, trust me, it’s correct :-p

You can think of it one of two ways.

1) the tyre is a completely square section, at any point down the sides the force pulling the material appart is equal to pressure x area perpendicular to that surface, so a 2″ tyre ar 50psi is the same as a 100psi tyre at 1″. Note that a force can never have any effec perpendicular to itself and the integral of all the other possible angles you could measure the force or area at is always zero (newtons laws of motion, an object at rest remains at rest etc etc). This is true at all points apart form the corners where the perpendicular area is bigger (the diagonal of thesquare not the flat surface), which is one of the reasons why even if you reinforce the sides to stop them buckling, pressurised structures usualy fail at corners.

2) imagine the tyre is round crossection (like it is), the two sides of the tyres don’t move apart from each other so the forces must be ballanced (newton again), so if you cut it in half and made two sides semi circles with some sort of stiff flat suface seperating them then the force on the join would still be equal to pressure x area, only there’s no weak corner in a circle.

You can even use the same maths to prove why sausages split along their length (axialy), never arround the circumfance.

Lengthways:
force = pressure x diameter x length
force/length = pressure x diameter

Cirrcumfrance:

force = pressure x cross sectional area
force = pressure x pi x r^2
force = pressure x pi x d^2 / 4
the length of the split is the circumfrance = pi d
force / length = pressure x pi x d^2 / (4 x pi x d)

force / length = pressure x d / 4

So for any sized sausage (or tyre) it will always split lengthways allong the bead as the force pulling it appart is 4x greater.

…but Im still not buying the whole exploding off the rim thing – at least not as a result of pressure; and I won’t until someone can give me a proper explanation (one that isn’t to do with floppy beads that hold up perfectly well with an inner tube)

If you’re so convinced the bead will hold it, and everyone that’s tried it is wrong, and the tyre manufacturers are wrong, try it.

He is right of course
that’s why larger volume tyres of similar thickness are rated for lower maximum pressures

Im not interested in trying road bike tubeless, happy with MTB tubeless though…..and Im not denying the existence of these “explosions”, I just haven’t heard an adequate explanation. I wonder if it’s kind of a high pressure “burp” which due to the low volume of the tyre causes it go instantly flat?

Observations are useless without explanations – that’s how progress happens.

The Ultegra wheels came with tubeless ready rims so I thought ‘why not’? The issue is no one seems to really do the tyres do they?

Schwalbe the One look great -but why no winter version?!!!!!

…but Im still not buying the whole exploding off the rim thing – at least not as a result of pressure; and I won’t until someone can give me a proper explanation (one that isn’t to do with floppy beads that hold up perfectly well with an inner tube)

In that case I would simply go ahead and try it. What could possibly go wrong. Fwi JRA suggests that the maximum pressure you should use with any sort of tubeless set-up without a road tubeless-specific tyre is 40psi, but I’ve run up to an indicated 60psi using cross tyres converted on Crest 29ers, so it’s a generalisation rather than FACT.

As far as the explanation goes, isn’t it just that the physical pressure of the tube literally jams the bead of the tyre against the hook of the rim and provides a physical barrier to it being dislodged in a way that air pressure on its own doesn’t achieve. Or is that too simple?

Schwalbe the One look great -but why no winter version?!!!!!

Because traditionally, over winter, roadies switch to nasty, hard, reinforced tyres with limited grip to avoid punctures from sharp things washed onto the road – think Gatorskins – except that up here, sharp things aren’t generally an issue?

I run GP4000s all year on the basis that I’d rather have fast and grippy tyres when the roads are more slippery rather than sloppy, slidey ones, but then I’m a feckless mountain biker riding on the road rather than a ‘proper roadie’.

Hooke’s law,

the force needed to extend or compress a spring by some distance is proportional to that distance. That is: where is a constant factor characteristic of the spring, its stiffness.

Bigger force = more stretch, put 100psi in a road tyre or 50psi in a MTB tyre and it’ll stretch the bead, when the bead gets bigger than the rim diameter all the air escapes. Stick a tube in there and you’re provding just enough aditional force to hold the bead under the hook of the rim preventing it stretching.

To overcome this road tubless tyres use a different material (carbon not kevlar or steel)in the bead, and a much more accurate/tighter bead that sits tightly under the lip.

It’s not a burp, that’s when the bead get’s pushed off the bead hook by cornering forces.

The Ultegra wheels came with tubeless ready rims so I thought ‘why not’? The issue is no one seems to really do the tyres do they?

Schwalbe the One look great -but why no winter version?!!!!!

Hutchinson do some training tyres.

As far as the explanation goes, isn’t it just that the physical pressure of the tube literally jams the bead of the tyre against the hook of the rim

The tube is only transmitting the force of the high pressure air. the tube itself has no rigidity at all and will explode at just a few PSI if not restrained by the tyre.

Do these explosions happen under static conditions or whist riding – riding I could understand…?

The tube is only transmitting the force of the high pressure air. the tube itself has no rigidity at all and will explode at just a few PSI if not restrained by the tyre.

Do these explosions happen under static conditions or whist riding – riding I could understand…?

If you really think you’re right, and everyone else is wrong, go try it. You won’t even get to 100psi, and if you do, don’t ride it becasue it won’t last long.

Pump a conventioanl tyre upto 100psi without a tube.

It will blow off the rim.

Then try re-fitting it, it’ll be slacker than a slack thing slacking off.

Stick a tube in there and you’re provding just enough aditional force to hold the bead under the hook

where has that force appeared from?

put 100psi in a road tyre or 50psi in a MTB tyre and it’ll stretch the bead, when the bead gets bigger than the rim diameter all the air escapes

Why does the same scenario not pop an unconstrained inner tube

lol – why do people keep asking me to try it – I just want to understand it
this is such fun 🙂

Why does the same scenario not pop an unconstrained inner tube

You don’t think an unconstrained innertube will pop at 100psi?

Because traditionally, over winter, roadies switch to nasty, hard, reinforced tyres with limited grip to avoid punctures from sharp things washed onto the road – think Gatorskins – except that up here, sharp things aren’t generally an issue?

But its chicken and egg then- because tubeless would be great for this- the punctures?..

You don’t think an unconstrained innertube will pop at 100psi?

Yes I do – that’s the point

Roadie tubeless isn’t so much about puncture protection, more about the rolling resistance. It’ll lose too much pressure before it seals each small hole.

It might save a few punctures, but you’d still need to top the air up every so often.

Yes I do – that’s the point

so why are we discussing them?

I can think of a few reasons why a tube would be enough to hold the bead together:
* The tube obays hookes law, so over the ~2mm or so join between rim and bead the force required to stretch that to say 4mm or 5mm enough to get it over the bead hook is the same as it would take to stretch the whole tube to 2-2.5 times it’s original size, i.e. quite a lot.
* As the tube conforms to the shape of the inside of the bead, at that point it’s concave (looking from the outside of the tyre, whereas the rest of the tyre is convex), so is actualy providing more area on the inside than the bare bead would therefore more force pressing the bead into the rim.
* it’s sealing small iregularities in the bead, if the bead was not a close fit liek tubelss beads are into the bead socket then the seal may only be a small cotact point arroudn the very ourside of the rim. Air would be free to equilise the pressure on both sides of the bead iself, thus the area that the pressure is acting on to press the bead into the bead socket with a force is small, thereofore the force is small. Make the bead big and soft (with a tube pressing it evenly, or just a bigger bead like tubeless) so it conforms to the rim and the area gets bigger, so the force gets bigger. More force = more friction.

I would think the puncture benefit of road tubeless is that instead of changing a tube you can just give a squirt of CO2 to replace any lost air ?

Definitely going to switch to tubeless after the winter, only waiting because I’d need new wheels and want to hold on until the weather’s a bit kinder to new shinies

I would think the puncture benefit of road tubeless is that instead of changing a tube you can just give a squirt of CO2 to replace any lost air ?

CO2 ‘curdles’ the sealent IME, although you could possibly use nitrous oxide instead.