[Closed] Tubeless - NO NO NO

You land heavily on the tyre if it does not have enough pressure and it nips the sides of the tyre.

You can pinch through the tyre, happened to me twice on proper UST tyres when an old, leaky valve was causing the pressure to drop gradually over a couple of rides.

Again though, new valve, checking pressure occasionally: no problems.

I continue to be surprised at those who think you can't pinch-flat on tubeless. The mind boggles.

Instead of pinching the inner tube inside the tyre, you pinch the tyre itself between the rim and the ground.

That said, it's not something that's ever happened to me, but then I do ride with higher pressure than a lot of the people on this thread (though lower than I would with tubes...)

I'm still not convinced. A pinch flat is when the tire nicks the tube. With tubeless this does not happen.

Are people meaning the tyre is getting pinched by the rim and hence the tyre is puncturing?

I am with grum on this...

Tubeless is good but not that good. If I was doing serious downhill I would rather have a good thick downhill tube and thick tyre. I always carry a spare tube

+1 for 819 rims they are bomb proof and mine have never had probs, Panaracer Fire XC UST too. I actually ran mine with NO sealant for ages as well. went on easy and lost minimal pressure over a week. That's pretty much my default setup

this thread should really be entitled...

"TOO LOW PRESSURE IN TYRES - NO NO NO"

When UST first came out the idea of sealant didn't exist, I ran UST tyres for about 3 years before I put any sealant in. I got one puncture in a Wildgripper, and 2 in Panaracer Trail Blasters, my only foray into Panaracers I must admit.

Pinch flats with tubes are caused by the RIM and the ground cutting the tube. Same thing is possible with tubeless except somewhat less likely I would guess, because the tyre is harder rubber and reinforced with tough canvas.

I smacked my rear wheel into a kerb the other day, tyre started going down. I was on my way to meet someone, so I stopped and pumped it up rather than fit a tube - twice in about 5 minutes.. then it stayed up - magic.

As for not sealing holes greater than 1mm - I rode over some glass once and put quite a cut in the tyre, probably 3mm or so. Sealant sprayed everywhere as I rode but it got less and less, and then sealed. I was astonished tbh. Unfortunately it happened again the following day (in a different place) and there wasn't enough sealant left 🙂

Oh and it says on Stan's site not to use Panaracer tyres, cos the beads are too slack.

This was a UST Panaracer, and to be fair there are plenty of tyres which can be very slack! Schwalbe are the only ones to be really consistent IME.

You'd have to be a right fatty to pinch flat through a side wall, and if you manage that then there really is no hope if you're running tubes...

Even as a confirmed tubeless Evangelical I know they aren’t perfect, there isn’t really a totally bullet proof way of doing pneumatic tyres, from my own experience (which is realy all anyone can rely on I suppose) I’ve found them to be better than Tubes, but you can still hole/slash a tyre or if the pressure gets too low they can roll/burp, tubeless is probably a slightly more maintenance intensive and perhaps costly way to keep you tyres up, but out on the trail I’ve had fewer issues with flat’s than I did when using tubes…

I would say to the OP give it another try, perhaps look for a different tyre and consider a dab more sealant (Better to have too much than too little)…
The failure you described could have a number of possible root causes, and it would be foolish to try and guess exactly what caused it or to suggest a tube would/wouldn’t suffer a similar fate.

At the end of the day I suppose removing a tube seems a bit counter intuitive to many and I can appreciate why, Failures will happen with both methods of tyre inflation, from what I’ve found less often with UST but that is only my experience, others may differ…

I’m a bit saddened by the UST converts who instantly jump on someone who doesn’t get on with UST, it is a bit unhelpful, disagree politely and then move on…

supinerider - Member
I've managed to do something similar with 819s and Nevegals but only when the pressure was too low (20psi - I'm about 70kg).

I've got less than 20psi in a mountain king 2.4 on my front XT rim, I weigh 84kg + kit!! Never any issues off road, but I take it carefull on grippier tarmac/concrete surfaces.

I was with the STW massive for 1 year and run tubless on Mavic 819

I did love them.....

But

2 punctures that were too big for the sealent to seal....
1 x slash while riding Torridon
Few burps but final straw was on Fort William DH course and High Roller LUST tyre burped and came off the front rim while horsing down a top section rock garden and caused me some pain.

Back to tubes for me!

Few burps but final straw was on Fort William DH course and High Roller LUST tyre burped and came off the front rim while horsing down a top section rock garden and caused me some pain.

Isn't that just because you were using the wrong tyres? LUST are not meant to be very tough are they - and you were riding a very rocky DH course. 😕

It IS possible to pinch a tyre much like a tube. Just far, far less common. Lots of people run too little pressure in their tubeless for the way they ride, you get very used to the durability and take it for granted and end up ramming rocks that you wouldn't go near if you had tubes in. The other thing of course is that if you do this sort of thing, you'll whack your rims a lot more.

Kbrembo wrote, "Few burps but final straw was on Fort William DH course and High Roller LUST tyre burped and came off the front rim while horsing down a top section rock garden and caused me some pain."

Oh come on feller, that's just poor equipment choice and I think you probably know it. If you want something that'll stand up to hard use on a DH course don't use something with "light" in the name. (that said I got on fine on off beat with standard nevegals run "ghetto" on Stans rims, but perhaps I wasn't horsing. If I was, I'd have fitted a more appropriate tyre)

Pressures depend on tyres. I run about 30-35 psi on the Patriot with wide Sun Singletrack rims and Kenda Nevagal tyres. On the 5 with Mavic 317s and Conti Speedking 2.3s I need about 45psi to stop them squiding around in corners.

coopersport1 - Member
+1 for 819 rims they are bomb proof and mine have never had probs, Panaracer Fire XC UST too. I actually ran mine with NO sealant for ages as well. went on easy and lost minimal pressure over a week. That's pretty much my default setup

this was on the bike you sold me:D

Grum..Northwind

From Maxxis website ref Highroller LUST

"The High Roller's tread design translates well to all mountain bike disciplines, including downhill, cross country, and freeride."

My main objective was the red run at Fort William so I wasn't changing tyres for a couple of runs of the DH

I am not being critical of LUST tyres but burps/tears/punctures can and do happen with any tubless tyre.

Just my experience and opinion.

Made me giggle^^^

"The High Roller's [u]tread design[/u] translates well to all mountain bike disciplines, including downhill, cross country, and freeride."

"The High Roller's tread design translates well to all mountain bike disciplines, including downhill, cross country, and freeride."

Yup, but there's more to the tyre than the tread pattern obviously, that's their standard blurb for all versions of the highroller. Would you take the 2.7 Supertacky XC riding? It's got the same description for that too.

I'm not saying you should have changed the tyres, I'm saying you should accept that if you use a tyre outside its design envelope you can't be too surprised if it goes wrong, and blaming tubeless for that doesn't make much sense. I took that risk myself using the Nevegals for the same job and it worked out but if it hadn't I'd just have accepted that my gamble didn't work out.

If only I'd known I could have saved myself some weight on the Mega and used LUST High Rollers instead of the Dual Ply Super Tacky 2.5s I did use. 😉

same thing happenned to me but with a tube, high roller on the front with X317 rim, had a slow puncture and knew it was a bit flat but ignored it, went round a corner a bit fast and bam, kerblamo! the tyre rolled off the rim. Hurt my knees. So it ain't just tubeless, it's any baggy tyres!

Woe betide anyone that dares to question tubeless tyres...

You're either thick or put them on wrong...

"Woe betide anyone that dares to question tubeless tyres...

You're either thick or put them on wrong."

Yip 😳

Ok now I am on Minnion 2.5 and 2.35 duel ply 60a with tubes and they will be getting used for all my riding which includes XC/AM..etc etc.

"I'm not saying you should have changed the tyres, I'm saying you should accept that if you use a tyre outside its design envelope you can't be too surprised if it goes wrong, and blaming tubeless for that doesn't make much sense."
Never "blamed" tubeless just stating a fact

"grum
If only I'd known I could have saved myself some weight on the Mega and used LUST High Rollers instead of the Dual Ply Super Tacky 2.5s I did use. "

Did I ever mention weight? or the mega?

As I said I really liked tubless and run them for a year but now gone back to tubes.

Ok end of this thread for me... Sorry for stating my experience of tubless

Chill out - are we not allowed to disagree with you?

We just pointed out that using a lightweight tyre for 'horsing down' one of the world's harshest DH tracks then having it fail, and saying that was the deciding factor in giving up on tubeless is a little silly.

The reason I mentioned the Mega is because that's another thing which is meant to be harsh on tyres, so I selected appropriate ones for the job.

But that's the point - dare to question tubeless on here and you may as well have called Jesus a c**t in a packed cathedral...

It doesn't suit everyone.

Not really - some people like it, some don't - but the fact that some people use it absolutely hassle free and others seem to have loads of problems suggests user error.

Surf-Mat - Member

"But that's the point - dare to question tubeless on here and you may as well have called Jesus a c**t in a packed cathedral..."

Nah, don't think that's true, there's legit criticisms and there's daft ones. And "my lightweight tubeless tyre didn't do very well on a world cup downhill course" is a daft one. Following it up with the quote from the Maxxis website just drives that home.

The people who insist it's always lighter or that it'll never puncture me annoy me just as much but they're not featuring much in this thread. Hopefully someone'll come along with a bmx tube ghetto conversion on an XC bike and claim it's lighter than an XC tube in a minute, then compare with an incredibly heavy cheap tube to back that up, then I can tear them to bits 😉

IS it normal to be able to mount real UST tyres by hand. I mean without reverting to tyre levers / spoon handles etc. I bought a NN Allgrounder and it was almost impossible to get on and off and absolutly refused to seal ( with WUL) up onto the rim.
I have a set of Conti Vert UST and they are just about mountable by hand without resorting to violence. Abit of WUL on the rim ( crossmax ) and a few pumps with a track pump and they inflate easily.
The set of RR also refuse to pop up onto the rim and are really tight on the rim, they too need tools to mount then sit in the belly of the rim and refuse to seal and pop up onto the rim.

to the OP , maybe try braking before you wang it into a corner too fast, you are asking the tyre to brake and turn at the same time.
cars and motor bikes should be slowed before the corner to the speed you carry to the apex, mountain bikes are more or less the same

Northwind.....

I live in the highlands and mtb 3-4 times a week and always do a weekend run-golspie,laggan,cairngorms,Torridon,etc.

Now calling me daft for turning back to tubes is an insult.

I was just stating my experiences with tubless.

Puncture at Golspie,rip in Torridon and a few burps. Some of the guys I cycle with have also had burps/punctures with tubless. Point is they are not perfect for all riders.

Next time you are up north give me a shout and we can talk tyres while we cycle.

I don't think it's exclusively a tubeless problem. I think slow pressure loss is what causes a lot of pinch/rolloff failures, whether it's a value problem of a small thorn puncture that doesn't seal. You don't notice the slow loss of pressure when you're hooning along until you hit a rock or corner and it just goes.

The only time I've burped a good tubeless setup is in a crash when I landed sideways on the front wheel and it pushed the tyre off the rim - BURP!

Northwind - fair comments!

Kbrembo - Member

"Now calling me daft for turning back to tubes is an insult."

It would be, but I've not done that.

Calling you daft for your comments on the LUST highroller however, I did do, and I don't think you can argue with it. Your attempt to defend it with the quote from the Maxxis website was if anything dafter. But by all means go on the offensive 😉

this was on the bike you sold me:D

but jesus is a c*nt. and a non existent one at that!

I like tubeless, most of the time it works for me.
A couple of punctures that didn't seal/1 big rip. is fine by me over the last few years. would have punctured anyway with tubes.
had it burp before, but it soon seated again when riding down the hill hitting other rocks to pop it back into place.
other than that i like it, if you get on with it great, if not fair enough. different strokes for different folks!

And singletrackmind,
i usually mount mine by hand. did have to use a tire lever for a tubeless 1.8 nobby nic, but other than that usually on/off by hand.