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What they don’t tell you about tubeless

It's not all roses with tubeless technology, here are some of the common pitfalls

You’ve probably heard lots of good things said about tubeless tyres (better puncture protection, comfort, rolling resistance and so on) but have you heard about the downsides? The tyres are a pain to fit, sealant makes a mess everywhere and there are huge compatibility issues, as we explain below.

- Tubeless tyres: With more choices than ever and Mavic entering the field is it time to switch to tubeless?

- Buyer's guide to tubeless tyres — all your options in new technology rubber

Tubeless might just be the best thing since the invention of the pneumatic tyre, or it might be a complete waste of time. The history of bicycle product development is littered with as many rubbish products as significant ones, in our view it's a big step forward (you may beg to differ) but as the technology stands today tubeless is not without its drawbacks - some of them are pretty well known, others less so.

Here then are some of the cons with current tubeless tyre technology.

No more punctures...

Before we get into the downsides, let’s start on a positive. One of the key benefits of a tubeless tyre setup is a greatly reduced risk of puncturing. The liquid sealant is able to seal smaller holes caused by glass, flint or stones and literally plug the hole because it dries very quickly.

When you witness it happening firsthand and are able to continue riding without needed to replace the inner tube is to be convinced this is the future.

...but doesn’t plug all holes

That said, tubeless isn’t invincible and the sealant won’t seal all holes above a certain size, generally about 6mm, because it’s simply overwhelmed by the speed of the air rushing out of the hole. So you might, in rare cases, find yourself with a flat tyre and sealant everywhere. Messy!

For really big holes that the sealant can’t fix, you have two choices, either whack a tube in or use a tubeless repair kit involving an odd rubber anchovy which you stuff into the hole to seal the tyre. They’re popular with mountain bikers but yet to be embraced by roadies, you can read a review here. So that's something else you need to buy. The price is creeping up.

And you still need to carry a spare tube

Yup, it’s advisable to still carry a spare inner tube even though you’ve banished them from your wheels, just in the rare event that the sealant can’t plug a hole.

Installation issues - the tyre just won't fit

This is the biggest problem with current tubeless tyres. Fitting a regular clincher tyre and inner tube is mostly painless, at worst you might need a few tyre levers, but after that, a small pump will get the tyre inflated onto the rim. It takes about 5 minutes.

Some tubeless tyres, however, can take much more time to get fitted to the rims and involve much cursing. The problem is due to there being no one standard that all rim and tyre manufacturers adhere to, and because you need a very good seal with the tyre bead on the rim, it generally involves a very tight fit. In some cases so tight that you need multiple tyre levers. We've known people to give up, it's that difficult. 

When you've got the tyre onto the rim, it's not all over. Nope, in some cases, you need a tubeless-specific pump, CO2 canister or compressor to deliver the big burst of air needed to pop the tyre up onto the beads.

Still, we could all be glueing tubs to rims still if somebody hadn't invented the clincher tyre...

Compatibility and lack of standards

Much of the problem with tricky tubeless installation comes down to the issue of compatibility between different brand rim and tyres, and a lack of a universal standard.

The issue is the wide variation in the rim and tyre size and the bead stiffness, which not only affects installation but also safety. Keeping the tolerances small is crucial to the success of the system because without an inner tube pushing the tyre bead against the inside of the rim there needs to be a really good fit to ensure the tyre doesn’t blow off the rim.

And the result is the current situation that sees some tyres being a breeze to fit to some rims, and the complete opposite being the case with another combination of tyre and rim brand.

However, there is hope. It looks like the bike industry has finally put its heads together and working towards updating the key guidelines and standards for rims and tyre design, including tubeless and clincher, to ensure all the issues of compatibility are a thing of the past.

- One step closer to a road tubeless standard? And why this matters to you

We’re yet to see what the standard actually looks like, but don’t expect a massive change or need to rush out and buy all new wheels and tyres, as it looks like some brands have been slowly transitioning towards the guidelines, as we expect Continental has with its latest GP 5000 tubeless tyres. It appears that the standard being adopted is based on Mavic’s Road UST which it introduced in 2017 and is based on its long-running MTB UST standard.

It can be messy

All that sealant invites the risk of a mess, and sometimes tubeless can be a messy thing. If you get a puncture while riding, unless you have mudguards you are going to spray sealant all over your frame, bum and back and anyone riding behind you. I’ve seen this happen and while it’s funny, it’s not nice at all.

When a tubeless installation goes wrong, you can be left with puddles of sealant on the floor or ground of your workshop/kitchen/office. Try explaining why there’s white gunk everywhere to your other half!

Tubeless can be heavier

The extra material needed to make a tubeless tyre, and in some cases, the rim as well with additional rim strips, plus the tubeless valves and necessary sealant, means that even though you’re ditching the inner tube, a tubeless setup can be heavier.

The tyres are generally heavier too. A Continental GP 5000 TL 28mm tyre weighs 340g versus 250g for a regular GP 5000 tyre. Removing the inner tube however does save you in the region of 100g but you're adding back  50-60g of sealant which negates some of the weight saved, and those tubeless valves are probably a little heavier too, and there's the rim strip if your wheels need it. 

So don't go expecting tubeless to shed loads of weight from your bike but in some cases it can save a small amount. Plus if you're carrying two spare tubes just in case, that's your weight saved added back to the bike. 

Tubeless or tubeless-ready… there's a difference?

Tubeless tyres fall into two categories: full tubeless and tubeless-ready.

Road Tubeless, as developed by Shimano and Hutchinson over ten years ago, and Mavic’s own Road UST, feature tyres that have an air-retaining coat of butyl rubber on the inside of the tyre and can be used without sealant, though it’s recommended for its puncture prevention.

Tubeless ready, which comes under many names and labels, means a tyre with a standard tyre carcass and omits the extra butyl liner. These tyres are lighter but the air-permeable sidewall requires the use of sealant for the system to work.

Some brands, like Hutchinson, make tyres in both tubeless and tubeless-ready versions. Mavic only makes full tubeless tyres using its UST designation. Some brands like Schwalbe only offer tubeless-ready tyres. 

Common names for tubeless tyres includes 2Bliss, tubeless compatible, Tubeless Easy, TLR, TL, Tubeless Complete and various other names. All of these tyres can be used with inner tubes, though you might struggle to get a full tubeless tyre and an inner tube fitted to the rim, it's commonly easier with a tubeless-ready tyre.

Most tubeless tyres on the market these days are of the tubeless ready variety because they are lightweight.

Limited choice

There’s no shortage of tubeless wheels, indeed nearly all wheel brands have added or made their wheels tubeless-ready. Where there is an issue is with the limited choice of tubeless tyres.

The situation has improved hugely in just the last couple of years with even Continental adding a tubeless tyre, and more recently Vittoria has got in on the action, but step back a few years and there were just a handful of options.

- Buyer's guide to tubeless tyres — all your options in new technology rubber

However, most of these tubeless tyres are top-end ones with big price tags. What we want to see is affordable tubeless tyres to make it more accessible.

Expensive upgrade

Wheel manufacturers have been quick to embrace tubeless and a lot of new road and gravel bikes are now being sold with wheels that are tubeless-ready, so you’re halfway there.

If you want to go tubeless, you’re going to have to buy new tyres. Now, unless you need to replace worn out tyres, then it does mean removing a perfectly good set of tyres with new tubeless tyres.

Tubeless tyres are often a little pricier than their clincher non-tubeless cousins. Continental’s new GP 5000 TL tyres were about €10 more at launch but shopping around now reveals they’re both about the same price, meaning you don’t have to lay out more cash to go down the tubeless route.

You also need to buy tubeless valves, sealant and rim strips if the rim bed isn’t sealed. There are kits you can buy with everything you need to get started like the Stan’s NoTubes Road Bike Tubeless Kit that has everything you need in one bag.

Might need new wheels

If your bike doesn’t currently have tubeless-ready wheels then you’re going to need to buy a new set of hoops. 

One alternative to buying new wheels if yours aren't tubeless-ready, and we're not recommending this, is to go ghetto. In the early days of tubeless, especially in the mountain biking world, it was common to use regular non-tubeless tyres and rims and use rim strips and sealant to achieve a tubeless setup. With the higher pressures involved in a road bike tyre it's probably safer to follow manufacturer guidelines and only use approved tubeless components. 

- 238 tubeless wheelsets — the most complete listing anywhere of your choices in new technology hoops

Easier to ding rims with lower pressures

Lower tyre pressures are very much on-trend now along with a push towards wider tyres, but the risk of running lower pressures does raise the issue of potentially damaging rims. This is especially true if riding a cyclocross or adventure bike off-road where rocks and roots can damage soft aluminium rims if the pressures are too low.

Sealant eventually dries out and needs topping up/replacing

Sealant is the magic ingredient that gives tubeless setups their big advantages over inner tubes, in being able to seal punctures.

Most are latex based but there are some latex-free options if you have an allergy to the ammonia content of latex, or worried about its oxidising impact on aluminium. Latex also doesn’t like carbon dioxide from Co2 canisters so that rules them out.

Sealant quality and variety have improved over the years and there’s now a vast choice on the market. Many are now biodegradable and don’t use ammonia, which means they’re less harmful and you can use a Co2 canister in an emergency. Some brands have developed sealant that claims to never dry out.

The liquid sealant required of tubeless setup doesn’t stay liquid forever, it’ll eventually dry out. I’ve had many alarming cases with road and mountain bikes when I’ve whipped the tyre off only to find the sealant completely dried out!

Muc-Off claims its sealant last up to six months after which you’re going to need to top it up. In most cases, the sealant is going to dry out long before your tyre wears out. Now you can either carry out checks every few months by popping the tyre off the rim, or an easier solution is to use something like milKit’s Tubeless Valve and Refill Kit.

It revolves around a clear plastic syringe and thin plastic tubes that lets you extract the sealant to see how much is remaining and whether a top-up is in order. It’s also useful if you’re swapping tyres as you can reuse the sealant and it removes the usual mess involved in swapping tubeless tyres.

Tyres glued to the rim

Another downside of sealant is when it comes to replacing a tyre and the sealant has dried and effectively glued the tyre to the rim, making removal of the tyre so difficult that people have been known to clamp said tyre into a bike work stand to break the seal.

We should add this does happen in isolated cases, very often getting the tyre off is a cinch. Again, this comes back to the lack of standards but it's gradually improving. Still, you only need to do an Internet search to find lots of people reporting issues with getting tubeless tyres off rims.

You might also have glubs of dried sealant on the inside of the tyre which you'll want to remove if you're moving the tyre to a different wheel, especially in the bead area where dried sealant has the potential to impact the seal on the rim.

The pros don’t use it (and that’s an issue for some cyclists)

For many cyclists, the fact that the pros haven’t embraced tubeless is as good a reason not to make the switch.

Professional cyclists, with their closed roads and support vehicles, still prefer tubular tyres for the principal reason that you can continue riding on a flat tyre long enough to receive a wheel or bike change. Johan Vansummeren famously won Paris-Roubaix despite riding the last 5km on a slowly deflating tyre.

Tubular wheels are usually a lot lighter as well because they require a much less complex rim bed design.

That’s not to say the pros haven’t dabbled with tubeless. Rolling resistance tests prove tubeless provides less resistance and a few WorldTour level time trials have been ridden and won aboard tubeless tyres.

Tubeless tyres have also been spotted at the cobbled classics in the past as well, a natural environment for the puncture resisting benefits of tubeless tyres to shine. Philippe Gilbert even won Het Volk back in 2008 on tubeless tyres.

But for the foreseeable future, the pros are sticking with tubular, not tubeless.

Sounds like tubeless is a terrible idea then?

If all that has put you off the idea of trying tubeless, we should end by saying that in our opinion the pros of tubeless tyres outweigh the cons. Getting the tyres on and off can be messy and a general pain but the beauty of tubeless is that it's not something you have to do often. There is hope for tubeless to become much more accessible and easier with the industry finally agreeing on new standard guidelines to maybe all these troubles will be a thing of the past and nothing more than teething problems.

Do you love or hate tubeless? Let's hear your thoughts in the comments section.

 

David has worked on the road.cc tech team since July 2012. Previously he was editor of Bikemagic.com and before that staff writer at RCUK. He's a seasoned cyclist of all disciplines, from road to mountain biking, touring to cyclo-cross, he only wishes he had time to ride them all. He's mildly competitive, though he'll never admit it, and is a frequent road racer but is too lazy to do really well. He currently resides in the Cotswolds.