To me, tubeless tires make a lot of sense for mountain bikes. In the event of a puncture the tubeless sealant will seal the puncture, often without the rider knowing it. Also, tubeless tires eliminate pinch flats. Pinch flats are where the tire is compressed, usually against a sharp edge or rock, and the inner tube is pinched between the tire and the rim cutting each side of the tube followed by a sudden loss of air – otherwise known as a ‘snakebite’. As pinch flats are eliminated, tubeless tires can be run at lower pressures which improves grip.
I’ve been running tubeless on my mountain bike for the past five years without a single issue. The same goes for my gravel bike, which I also run tubeless .
Reading about tubeless for road bikes online, opinions seem polarized. Half the people say they love tubeless, hardly ever have punctures and they’re never going back to tubes. Others say that tubeless is more trouble than its worth on a road bike and there’s no benefit. I’ve also read that there’s a learning curve and correct setup is important. I agree there’s a learning curve based on my experience and wanted to share that experience and what I learned from my mistakes.
The Campagnolo Bora WTO wheels on my Colnago V1-R are tubeless ready, so always one to experiment and tinker, I decided to set them up tubeless.
The Bora WTO wheels are described by Campagnolo as 2-way fit, which means they can be set up either tubeless or with tubes. Interestingly Campagnolo doesn’t offer a tubular version of this latest wheel, which suggests they consider tubeless has made tubular tires obsolete. The WTOs don’t require tubeless tape, so that was one less step in the tubeless set up.
After much research, I bought a set of Vittoria Corsa G2.0 TLR tires, as they reviewed very well here:
https://www.bicyclerollingresistance.com/road-bike-reviews/vittoria-corsa-speed-g2
I’ve set up tubeless tires on my mountain bike and gravel bike, and never had a problem. The Vittorias were a little difficult to mount on the rims, moderately more difficult that the Conti GP5000s they were replacing, but the bigger challenge was getting the beads to seat. No matter what I did, I couldn’t get them to hold enough air to seat. I was using a compressor, soapy water, removed the valve cores, but no joy.
After some internet research I found a couple of tips:
One suggestion was to use a cinch strap such as this to force the beads to seat when air is applied
The other suggestion was to install a tube first, which will seat the beads, then remove the tube keeping the bead seated on one side. This was the option I tried, successfully. With the bead seated on one side of the tire it was much easier to seat the other bead when air was applied.
Once the tires were installed, I removed the valve cores and injected ~60ml of Stan’s tubeless sealant with the Stan’s injector. Job done!
The bike rode great, it felt silky smooth and the tires seemed to roll fast.
Over a couple of weeks and several rides I had a few incidents with punctures, which resulted in spraying sealant. I found it odd that I had two punctures in 150 miles just after I switched to tubeless, when I’d previously gone 1000’s of miles without a single puncture. The sealant would do it’s job, seal the puncture after a few seconds and allow me to ride home (albeit with some pressure loss), but when I got home and reinflated to my normal 100 psi, I’d find that sealant would start to leak again, either immediately, or at the start of the next ride. The sealant didn’t appear to be permanently sealing the puncture.
After being advised the Corsas aren’t well suited to the rough roads I ride, I was recommended Schwalbe Pro One TLE tires so I ordered a pair along with some Stan’s Race Sealant from Merlin Cycles.
TLE stands for tubeless easy which Schwalbe claims makes the tires easier to mount. One concern I had with tubeless is that if you have a puncture the sealant won’t seal and you need to install a tube to get home, then as tubeless tires can be more difficult to mount (because the beads are stiffer), installing a tube at the side of the road could be difficult. I found I could install the Schwalbes easily without tire levers and seating the beads was a breeze. I made sure the beads were either side of the valve, pushed the palm of my hand down on the tire in the valve area, applied air from my compressor, the tire inflated and the beads seated with a few pops and cracks. No soapy water, no installing a tube first, no effort.
I didn’t realize that Stan’s had two different sealants – a standard and a race sealant. The difference is that the race sealant contains some larger crystals and can seal larger holes, so I tried the race sealant thinking this might provide a permanent fix in the event of a puncture.
I installed the Race sealant with the injector, as I normally do, then later read that Stan’s recommends not doing that as the larger crystals can clog the valves – but I didn’t have that issue.
The Stans Race sealant worked no better than the regular sealant in terms of permanently sealing a puncture to allow me to run 100 psi (or above 65 psi).
After some posts on facebook cycling groups it was recommended I try Orange Seal as some considered it better than Stan’s. There are two formulations of Orange Seal, a regular and an endurance version. The endurance version is recommended to seal smaller punctures but is designed to have a longer life before drying out in the tire. I’d read that the endurance sealant is preferred for road bikes.
Whichever sealant you decide to use, make sure you shake the bottle very well before filling the tire with sealant, otherwise you’ll fill the tire with the liquid latex without the crystals/particles that do the sealing. I noticed the viscosity of the Orange Seal change very noticeably when it’s well shaken, making it harder to pour. I think this shows that over time the crystals will settle at the bottom of the bottle with latex at the top.
In the event of a puncture, I’ve also been advised (by Stan’s tech support) that you should let the tire sit at low pressure for a while to allow the sealant to seal before inflating to the normal riding pressure for – otherwise you run the risk of blowing the sealant out of the hole before it’s had time to seal.
When setting up tubeless tires, I also believe that the tire should be airtight on the rim without sealant. Install the tire first without sealant and make sure it’s holding pressure before installing the sealant (either through the valve or by unseating one side of the tire).
What to do when the sealant can’t seal a puncture
As I repeatedly had punctures that the sealant wouldn’t permanently seal, I started looking at how to make a permanent seal without the sealant.
If the hole is too large for the sealant to seal, then you can always patch the tire on the inside.
I patched a 3mm hole in a tubeless tire using a regular tube patch. I subsequently ordered a patch kit specifically designed to patch tubeless tires, although I’m not sure how these differ from the patches used for tubes. The patches are actually smaller, which seems odd to me.
The tire patch seemed to work for a while, but eventually started leaking sealant out of the hole the patch was there to fix.
There are also several options available to allow larger holes to be plugged at the side of the road during a ride.
This is a Stan’s DART, which is designed to seal larger holes (> 5mm) in tubeless tires that the sealant can’t seal on its own. Once pushed through the puncture, with the supplied application tool, barbs on the DART secure it in place inside the tyre, while the feathered material fills the damaged section and protrudes out of the tyre.
Stan’s says that the excess material wears flat quickly and cannot be felt while riding (even with road tyres), so doesn’t need to be trimmed.
The rubbery, feathered material is treated with a chemical compound designed to react with Stan’s sealant to form a more secure bond with the edges of the damaged section.
I tried several times, wasting several DARTs, but could never get the DART to penetrate a road tire and work as it should. I think mountain bike or gravel tires are softer and more supple than road tires designed for low rolling resistance and higher pressures, which is why the DART works better on mountain bike/gravel tires.
DynaPlug has also been highly recommended.
The disadvantage I see compared to the DART (apart from being twice the price), is that with DynaPlug, the plug needs to be trimmed after the repair, whereas the DART will wear flat with riding.
Another other is the bicycle equivalent of the tradional tire plug:
I tried to use this to repair a puncture that wasn’t sealing, but I was unsuccessful as the plug blew out of the tire at higher pressure.
None of these solutions should have been required for the non-sealing punctures I had, as they were all small thorn punctures or nicks less than 3mm in length.
Conclusions
I persevered with tubeless tires on my road bike for a full season. I tried two different tires from two different manufacturers, three different sealants, and three different methods of fixing a puncture the sealant wouldn’t permanently seal.
In the end I switched back to using tubes.
I’d had very few flats with tubes over many years and several thousand miles on my road bikes. I tried tubeless on my road bike out of curiosity and because of the ‘convenience’. I’ve never spent as much time ‘fixing’ tire problems as I did when I was running tubeless tires on my road bike.
Granted, I could always ride home after getting a flat with tubeless – and I’d be alerted to the fact I’d flatted by the spray of sealant on my legs and bike frame. I seemed to be flatting much more regularly with tubeless than I had been with tubes, that could have been due to tire choice.
The biggest issue however, was that following a flat, the sealant didn’t seem to be forming a permanent seal and none of the other options seemed viable either. So I was stuck with an expensive tubeless tire that was useless unless I installed a tube.
It got to the point where I could consistently repeat the issue. Following a puncture, the sealant would seal and pressure would drop to around 65 psi. I would then inflate to 100 psi, and then either straight away, or (more annoyingly) at the beginning of the next ride, the sealant would start spraying out of the puncture site again. Until the pressure dropped to around 65 psi, then it would seal.
This for me, explains why tubeless works so much better with mountain bike and gravel tires that generally run pressures below 50 psi. The sealant works well at pressures below 65 psi but at pressures above that, the pressure will blow the crystalized sealant out of the puncture hole.
Some might argue that one of the benefits of running tubeless is that you can run lower pressures, and that I shouldn’t be running 100 psi with tubeless tires. It’s true that I could run lower than 100 psi, but I’m a big guy riding on rough roads. I’m not going to run as low as 65 psi. I might not get pinch flats running tubeless tires at 65 psi, but I could quite easily damage an expensive carbon rim, and I’m sure rolling resistance will be noticeably higher at 65 psi than 100 psi – and I don’t want to run tubeless tires if it means I need to compromise my ability to ride fast.
Incidentally SRAM and ENVE have online tire pressure guides. Based on these, SRAM suggests I should be running 87 psi front and 92 psi rear, and ENVE recommends 95 psi front and rear. So I’ll stick with 100 psi.
https://axs.sram.com/guides/tire/pressure
If you flat with a tube, you can either patch the tube or replace it. Tubes are inexpensive to replace relative to a tubeless tire. It doesn’t really take that long to change a tube, punctures happen infrequently, and by using tubes the tires are easier to install and you don’t need to contend with the mess sealant makes.
My experiment with tubeless road tires is over and I don’t think I’ll be going back, unless there are some proven advancements that fix the issues I’ve explained here.