DangerousDanR

As promised, when I needed to change a tire I would do a small experiment to demonstrate how well or poorly a road tubeless tire will seal up after being punctured with s drywall screw. Except I decided to use a cement backer board screw because that was the bucket that was closest at hand.



I use Orange Seal because they make a winter version that is still a liquid in fairly cold temperatures. I am not sure what flavor of Orange Seal was in the tire to begin with, but I topped it up with 50 ml of Orange Seal Endurance seal.



With the preliminaries out of the way, let me introduce the guest of honor. This is a Conti GP5000 TL with cord showing where there should be tread. The tires were inflated to the setting I use on the tandem, 90 PSIG.






The first test was a single screw directly into the tread...



When the screw was removed and the tire was spun, the stream of sealant fizzled out fairly quickly, about 20 seconds. The result was an orange spot on the tire and a pressure reading of 61.5 PSIG, so while we could ride on that we would probably stop and pump it up.




That was too easy. The main event was the infamous double puncture through tread and sidewall. I had to slightly deflate the tire to make that happen. Then I ran the pressure back up to 90 PSIG with the screw in place



This pair took a lot longer to seal, but when the spitting stopped the gauge read 14.5 PSIG. Not enough to ride, but I pumped it up to 90 PSIG and both the sidewall and tread punctures remained sealed.




So, would I knowingly ride on this tire? If I had to, yes. But since it was going in the bin anyway, to the bin it went. The replacement was fairly easy to put on the rim.
Good tools help make it an easy job. With my two spare hands the tire was on the rim and holding air pressure without sealant in about 5 minutes.



Am I going to stick with road tubeless tires? Of course. Yes, they are harder to mount (at least GP5000s are), but that tire ran a lot of miles on some very bad roads with zero flats. For anyone who wants to gloat and say "but you don't have a work stand, those clamps and a compressor when you are touring", well yeah... but so what. I have also not had any punctures that I was aware of with the GP5000s but not the previous Schwalbe Marathon tires, which are a pretty good touring tire.

tomato coupe

Okay. What did we learn from this?

DangerousDanR

My intent was to demonstrate that road tubeless and good sealant is not as fragile as some people like to say.

I have had 4 tubeless fails. All involved failure of the sidewall. Three of them were large slices in Schwalbe Pro One tubeless while commuting. I walked all three home. One was a Conti GP5000 which had the bead separate from the rest of the tire. I also walked it home. In all four cases, the tire stayed seated on the rim. I consider that to be a big safety feature.

If I ever have to repair a tubeless tire on the road I will be stuffing a tube in it, so I can inflate it with my hand pump. At home, I have a compressor so I use it.

tomato coupe

People cite different reasons why they don't like tubeless, but fragility is not one of the common reasons.

And yet, this makes tubeless seem kind of ... fragile.

Broctoon

Over the past couple years I’ve been switching to tubeless on most of my bikes. Sometimes they are a pain to set up initially. I’m getting better at it and usually don’t have much trouble now.

For me, the biggest reason (and the only really compelling one) is puncture resistance. Or more accurately, puncture self-sealing properties.

There are are other pros and cons that have been discussed ad nauseum. For me it comes down to this: I used to get a lot of flats. The only way around this seemed to be using super heavy tires, super heavy tubes, or other heavy, clunky devices to keep thorns from getting through. Or usually a combination of two or three of these stupid solutions. I live in a desert, and we have a lot of goat head thorns. These were the cause of 90% of my flats, and there’s almost no way to avoid picking them up frequently.

On all my tubeless tires, the thorns are not even a concern. If for no other reason than this, tubeless setup is a totally worthwhile investment for me.

Thanks for the fun test/demonstration, DangerousDanR

shelbyfv

I'm impressed the Orange Seal filled holes that large.

Sy Reene

I'm starting to think that if there's a way to mold hardened Orange Seal into a complete tire, the industry might be on to something.

Chandne

I like Orange Seal the best. This is a good test. Thanks Dan! One nice thing about road tubeless is that if you get a puncture on a fast twisty downhill, the chances of crashing are reduced. I'm waiting for my Zipps and will convert to tubeless when they come in.

Kimmo 

Although, when you ride over a screw, it's just punched through the tyre like a nail, and I presume that was too difficult to reproduce for a test, right?

The hole left by a screwed-in screw versus a nailed-in screw is gonna be a lot tidier, I bet.

Seattle Forrest

I got two flat Pro Ones, both sidewall cuts, almost back to back.

rsbob 

Picked this up last week, lost 3 lbs pressure. After spending 10 seconds checking it out, I rode it home 4 miles before extraction and plugging. Conti 5000 TL with Orange sealant. Plugged it and took on a 40 mile ride with zero pressure lost. Tubeless are a marvel. No issue seating on my Nir rims.

WhyFi

People that use OS (and some other good sealants) have been saying this for years - it works on relatively bad punctures and it holds at road pressures. The ****show caused by early adopters carrying over Stan's from the MTB world, and the subsequent parroting of "tubeless doesn't work for road!" has been tough to overcome.

himespau 

So, is it better to remove the item right away? I'd be afraid that, if I left the screw/nail in there, it would damage the rim.

WhyFi

Yeah, definitely. I don't see an upside to leaving something in, but there's certainly downside, like rim damage or making the tire damage worse. I suppose that, if you're not too confident in your sealant, you might leave something in until you're in a better location to deal with it, but I don't think that I'd personally go any further than the next shady spot that's clear of the traffic lane.

DangerousDanR

Riding the tandem to puncture the worn out rear tire only would have been a trick that I didn't want to attempt, so I put those screws in with a screw gun. They spun in the tire when they bottomed out. Backerboard screws have very sharp threads and the holes were about what you would expect if I had used a drill bit of that diameter instead.

When I first used road tubeless I had a lot of trouble with leaking in two places:
1) valve leaks
2) tape failures

Using the Orange Seal has eliminated both.

And mostly I did this because I told DiabloScott that I would:

I offered that I would run a drywall screw through a tubeless tire that was wearing out and voiced my opinion that the tire would hold air. The answer to this question is that at least one GP5000 32X700C that was completely worn out after two years on a tandem did indeed hold air when some fool went at it twice with a screw gun and backer board screws.

So DS... Do you like them baked or fried?

tomato coupe

Have you ridden on the wheels after the screw experiment?

On edit: Never mind ... I forgot that you installed new tires.

tomato coupe

Clearly, one of the problems with Orange Seal is that it turns your hubs, nipples, and valves orange.

DangerousDanR

I did not, but it held 90 PSI for about 10 minutes before I swapped the tire. I have absolutely no doubt that the punctures would not have prevented me from using that tire.

tomato coupe

Holding pressure for 10 minutes might not be enough. On several occasions I've had punctures on my road bike that sealed up and got me home without any problems. (Other than the mess, of course.) They seemed fine when pumped back up to normal pressure, however, the puncture re-opened within a mile when I rode on them. So, although they were rideable with sealant alone at low pressure, they needed to be plugged to work at normal pressure. YMMV.

WhyFi

I've only had a couple punctures open back up and they were both right on the edge of that 5-6mm limit of Orange Seal. Both rode fine for hundreds of miles until smacked just right by a bridge seam and pothole, respectively. This was at 70-75psi, though, so the puncture size threshold might be a little smaller at 90.

rsbob 

That was my concern as well and checked the tire pressure every mile or so to make sure the rim was not being damaged. If I had lost considerable pressure, I would have removed the nail immediately and plugged it road-side. Since I had never plugged a tubeless before, I wanted to do my trial run at home. After plugging which was far easier than the old way of replacing a tube or patching, I would not hesitate to pull the nail/screw and plug on the road.

PeteHski

I've been using Pirelli TLR tyres recently (Cinuturato for training rides and a couple of local Sportives and now P-Zero Race for faster summer Sportives). Both these tyres are super-easy to fit on my Giant SLR carbon rims without tools, not even a plastic tyre lever. Seating them does require a boost track pump (or compressor), so that's the only minor downside for anyone with only a regular track pump. Just out of curiosity I did try to seat them with a normal track pump and failed miserably. I haven't had to plug one of these tyres yet, but my experience of plugging mtb tubeless has been 100% successful over many years. Which is why I was always keen to go road tubeless. I used to regularly get flats with tubes (maybe once or twice a month) and with tubeless I now don't. I'm 2 years in now with road tubeless and yet to experience a single flat. I almost want to get a flat just so I can test my Dynaplug repair tool.