Fast, Comfortable, Puncture-Proof: Tubeless Tyres for Road Bikes
Non-professional cyclists are hardly ever faster than professionals. When it comes to time per distance, they clearly lose. But they are definitely in the lead in terms of technical innovations. While the professional peloton was still discussing the pros and cons of disc brakes on a road bike, amateur athletes were already riding them and were happy about the great braking performance – especially in wet weather. History seems to be repeating itself right now – with tyres. More and more amateur cyclists switch to tubeless tyres.
As the name suggests, these tyres do not have inner tubes. Tubeless tyres look very much like regular tyres, but of course they are processed differently and need a sealant in order to be completely airtight. Just like tubular tyres they require a special wheel. But modern clincher wheels are already fit for this tyre technology, which can be seen from labels like tubeless-easy or tubeless-ready.
Tubeless technology is nothing new. Basically, car tyres work the same way, although they are of course built with other materials such as steel mesh. In the mountain bike sector, this system has been around for well over a decade, almost every gravel bike is delivered with tubeless-ready wheels and tyres, and in the road bike sector this type of tyre is currently experiencing a real boom. With good reason!
Lower air pressure improves rolling characteristics and reduces rolling resistance
“I can ride a tubeless tyre with lower tyre pressure, which in turn leads to higher traction and gives me more comfort on rough road surfaces and rugged tracks”, explains Felix Schäfermeier, Schwalbe’s Product Manager Road Bike and responsible for the development of the new Schwalbe Pro One TLE tubeless tyre.
Speaking of air pressure: the wider the tyre, the less air pressure is required – which also reduces rolling resistance. Why? “The contact area is smaller, i.e. wider, but much shorter,” says Schäfermeier. For this reason, many amateur cyclists ride 28-millimetre-wide tubeless tyres – many manufacturers offer tyre width from 25 to 32 millimetres.
“In addition, the rolling resistance is also improved in comparison to clincher tyres, because the tube is missing,” explains Schäfermeier. This is because tube and tyre are two separate products that “rub against each other”.
By the way, due to the missing tube, cyclists are immune to a very special defect: the so-called snake bite. This kind of puncture occurs when the tube is pinched between the rim and the casing on rough surfaces such as cobblestone passages or when there are potholes on the road.
Sealant for self-healing
The sealant, which is filled into the tubeless tyre, closes small holes and cuts during the ride. The self-healing powers are an invaluable advantage, especially on long rides, although a spare tube should always be carried along for safety reasons.
Great arguments – but why don’t the pros use this system then? On the one hand, because road cycling is very conservative – see disc brakes, e.g. – and many team mechanics have a lot of decision-making power when it comes to the equipment used. On the other hand, because good performance in all areas depends extremely on the interaction between wheel and tyre.
This was not always smooth in the past. In other words: Certain wheels and tyres do not harmonise well due to tolerance variations and construction. This is usually already noticeable during assembly.
The perfect match – wheel and tubeless tyre
If wheel and tyre match, it is very unlikely that circulating horror stories about mounting the tyres come true. With a good combination of wheel and tubeless tyre, the tyre is usually mounted in a few minutes, lies well in the rim when inflated and holds the air well for the time being without sealant.
“If this set-up of wheel and tyre matches perfectly, a tubeless tyre combines the best features of clincher and tubular – including run-flat properties,” explains Schäfermeier. The latter is especially important for professionals, as they still want to and sometimes have to continue on the rim for a few hundred metres during the race.
Schwalbe, like some other tyre and wheel manufacturers, have drawn up a compatibility list for the tyre and wheel set-up. The possible perfect match is assessed according to three important characteristics: assembly, inflation and jump-off safety. The latter feature in particular is – as the name suggests – safety-relevant. Find the list here.
If there is a really long, deep cut in the tyre, even the sealant won’t help you. In this case, riders will have to mount the spare tube into the tubeless tyre, but this is also the case with clincher tyres; and new tubular tyres have to be glued onto the rim en route or the personal support vehicle will have to be called.
Schwalbe focuses on tubeless tyres for road bikes
Tyre manufacturer Schwalbe is so convinced of the tubeless technology that they have discontinued tubular tyre production in fall 2019. “Furthermore, there are no new developments in the field of tubular rim technology,” explains Schäfermeier.
The top athletes follow the company’s path, too – and successfully so. Sebastian Kienle, a very equipment-oriented long-distance triathlon pro, approached the company and asked to test the technology. He was quickly convinced, also of the puncture protection, because Kienle didn’t have to change the tyre at the European Championships in Frankfurt despite it being cut by a piece of broken glass.
“The tyre pressure dropped from 7.5 bar to 3.8 bar, but the data remained the same. Despite less air pressure in the tyre he didn’t have to use more power to ride at the same speed”, explains Schäfermeier. “This is due to the fact that Schwalbe’s Pro One has extremely good flexing characteristics even at low air pressure,” says Schäfermeier.
Prof Team Canyon/SRAM-Racing races on tubeless tyres
Also, the female riders of team Canyon/SRAM-Racing were convinced by a real-life test. “At the beginning of the 2019 season, we specced one half of the bikes with tubular tyres and the other half with tubeless tyres to offer them a choice. From July onwards, the entire team rode on tubeless tyres,” Schäfermeier recounts.
This is also due to the smoothness and better controllability of the new tubeless models. “They are easier to control at their limit areas than tubulars. This is because they deform more naturally and do not have such a narrow limit area,” says Schäfermeier.
This is made possible by their construction. A tubular tyre consists of glue, up to four layers of carcass and the sewn-in tube. “Due to this design the contour of the rim pre-forms the tyre, as it rests on the rim and not inside of it. It can become angular, to exaggerate, and suddenly tip over uncontrollably in a bend in the limit area,” says Schäfermeier. With tubeless tyres the contour of the rim is not important for traction.
Already in the top 5 with tubeless tyres at 2015 Paris-Roubaix
Schwalbe’s enthusiasm for road bike tubeless technology is no coincidence. The company had been working on this design for road bikes for more than five years. They celebrated their first real success in 2015 – completely unnoticed by many. “In 2015 we used our first tubeless tyre at Paris-Roubaix,” says Schwalbe’s Felix Schäfermeier. Martin Elmiger of former Swiss team IAM finished fifth without a puncture in the Hell of the North. “One could say, that this was the predecessor of our current G-One gravel tyre,” says Schäfermeier.