Road Tubeless: An Alternative Perspective
WHY WE ARE RELUCTANT TO SUPPLY/FIT TUBELESS TYRES! .. Enjoy!!
After fitting many hundreds of tubeless tyres to customers wheels, our experience forces us into a position that anyone who wishes to ride tubeless needs to have some experience of managing tubeless fitting/care themselves and similarly should know the risks which range from the slightly irritating to the downright troubling in our view.
WE ARE TALKING ONLY ABOUT ROAD TUBELESS TECH HERE .. not MTB tubeless.
There are definitely people who swear by road tubeless. If you’ve had a positive experience then this article probably isn’t for you! It’s targeted more at people who are considering tubeless - or as we see often … people who have a niggle that they are missing out on a huge potential improvement in their cycling life.
We feel that this is mainly because magazines seem to just regurgitate the untested and often inflated claims (made by the makers themselves) about how wonderful tubeless tyres are - even continuing to rave about certain tyres merits after the manufacturers have had to pull them from production due to their ineffectiveness. There is virtually no critical analysis we feel. Having worked with thousands of road-tubeless users over the last 10 years - the following is a summary of our experiences.
Our customers report more problems caused by tubeless than every other problem put together! This page is an attempt to summarise the many challenges presented by road-tubeless setup and usage.
And if of course you do decide to try them yourself rather than rely on our quite uncompromising perspective please note that we strongly recommend HUTCHINSON (durability and all-season usage) and SCHWALBE (full-on speed and decent durability) tubeless tyres. They have proven to be the best and most reliable performance tubeless we have used. And most importantly the easiest to fit and inflate. Not too tight that you worry your rims will break. REMEMBER NEVER FORCE A TYRE ONTO A RIM. BREATHE HAVE A CUPPA. TALK TO US!
Here we go - starting with the petty and building up to a more considered and serious critique.
1) Tubeless is messy. No way round it. Even if you're careful and you don’t end up spraying your shed walls with it … your valves will still clog up with it. Think about valve cores a moment: So small and delicate and important and designed to allow air to pass just one way at a time. Not designed to be squirted full of liquid rubber. Just getting going now.
2) Tubeless is fiddly and time consuming. Sealant needs changing every 3-9 months. Leave your race wheels over winter and you've a messy start to season.
3) Tubeless requires specialist tools.
4) Tubeless still needs you to carry spare inner tubes.
5) Tubeless Tyres are on the whole tighter to fit than clinchers due to the need to achieve a seal. The problem has been made far far worse because that there has been no standardisation of tubeless rim/tyre sizing, resulting in a huge and troublesome variance between tyres and rims. (The new EU standards will over the coming years help tyre/rim makers to get it right. However we are still years away from there being a meaningful standardised correspondence between tubeless tyre and rim sizes. (Really good article here)
In fairness one might say this is not a ’fault’ of tubeless so much as a teething issue. We do agree with that up to a point. On the flipside: most customers do not know that the industry is flying-blind on this one and that they as the end-user are the ones bearing the pain of this. Our experience is that most people feel its they themselves who must be doing it wrong! We don’t think that is acceptable.
Until such times as the standards kick-in, it does mean that many rims and hands will continue to get damaged by over-zealous desperate tyre-levering of too-tight tyres . (Never force a tyre on - never!. Know that you don’t need to. Just try a different brand as it will almost certainly be a slightly different size). Do follow a good tubeless tyre fitting guide too as there are right ways to fit tubeless tyres to tubeless rims that many people just are not aware of.
And don’t forget that if you are struggling to fit a tyre at home - then it’s going to be much worse when you’re stuck at the side of the road in winter trying to get your tubeless tyre off to put an inner tube in after a tubeless tyre has deflated.
6) Tubeless can also be a nightmare to fly with if you are made to deflate your tyres! Tubeless works by forcing the tyre up onto a shoulder of the rim that aids sealing. The tyre is held there by air pressure. If you deflate your tyre it can pop off the shoulder and back into the centre of the rim … and then you get a lovely liquid-latex encased bike! Nice.
True story: We had one guy who flew to Spain with his bike and deflated his tyres as requested. The above happened to him. He rang us up screaming from his hotel room to say he’d put his wedding suit in with the bike to keep it nice and flat. Oh dear!
7). Tubeless is still somewhat unpredictable, possibly because many tyre brands have so little experience of tubeless tech that their tyres can feel a bit cobbled-together. (Sorry Continental but your 18 months experience in this field does you no credit in our view - your GP5000 clinchers are in our view/experience the best tyres ever made... the GP5000TL tubeless might just be the worst in spite of all the heady claims made by the manufacturer: we here lots of people describing repeat sidewall leaks, super tight to fit, with measurable variances in bead sizes from tyre to tyre).
STOP PRESS: At time of writing (Aug 21). Continental have just announced they are ending production of the 5000TL after only 18 months. Frustrating. All the more annoying too because independent tests by Aerocoach had already revealed the 5000 clincher to be faster than the 5000TL tubeless! https://www.cyclist.co.uk/news/5702/which-is-faster-continental-gp5000-tubeless-or-clincher (as an aside it is fascinating that this really good magazine article goes into the detailed numerical testing of these tyres and accepts that the clincher is faster than the tubeless but still advises readers that tubeless is the best option ..”despite these interesting results” simply because it is tubeless. Nothing more! Quite bizarre to fashion an article around identifying precision data and then to ignore your own findings. It is just this sort of conclusion that the page you’re reading now seeks to rebalance by suggesting an alternative and experience-based perspective!)
8) This next one is a bit of a ticking time-bomb. If you have lightweight wheels with alloy nipples and your tubeless seal is not perfect from the get-go then some tubeless sealants will seriously corrode the nipples which can lead to repeat spoke failures and ultimately require expensive rebuilds.
High quality alloy nipples have been around for decades now and have huge performance advantages for racers. They can save up to 25 grams per wheel at the rim. This is significant. (And high quality alloy nipples such as the Alpina, Sapim and Pillar that we employ in our own lightest builds should easily last the expected lifetime of the wheelset more here). And most endurance wheels use heavier and more durable brass/nickel nipples which are not affected by toxic sealants.
The chemistry involved in alloy nipples being attacked by some tubeless sealants is thus: Latex based sealants require chemical additives to stop the sealant from coagulating in your tyre. Ammonium based additives such as Ammonium Hydroxide, are the most common. If the sealant breaches the rim to a significant degree at either the valve or at the rim tape, it can get inside the rim then the ammonia can activate bi-metal galvanic corrosion between steel spokes and alloy nipples.)
This happens when tape or valves are not correctly fitted or sized. if this happens to you you will see sealant temporarily oozing out of the wheel at the spoke nipples or valve as you inflate. If you are struggling to get a seal and you see this happening you need to stop and remove tyre, valve and tape and flush the rim and then dry it thoroughly which can take days.
In practice however most people just keep firing in more sealant until eventually they get some sort of seal - which is often possible to achieve. What they don’t know is that this is sewing the seeds of future damage to the wheel as by then lots of toxic sealant is bathing the spoke nipples. It can’t escape either by the way. It initially seeps out of the inside of the rim on inflation. However, being sealant it qiuckly plugs these gaps trapping the rest of the sealant inside! Ironic!
Galvanic corrosion is a highly destructive and aggressive form of corrosion that strips the alloy nipple. At K1 we have never warranted the use of Latex based sealants for this reason. Even so, it can still be hell for end-users because manufacturers of sealants are often not that clear about what is in their product. For example synthetic Latex does not need ammonia where real Latex does. What a costly mess. Many wheel brands seem oblivious of this key issue stil - which ultimately will cause avoidable problems for many users.
Our main question: Does anyone really need to be taking these sort of risks with their expensive wheels for no advantage whatsoever! And sadly this question becomes more urgent if you read on..
9) Too low Tubeless Pressures come with a risk of rim damage! Think about it. We keep hearing that low pressures enabled by tubeless tyres avoids those nasty snakebite punctures. Snakebites occur where under road impact - your inner tube gets literally sliced open as it gets caught between road and rim. You inspect your inner tube and sure enough the 1cm long cut looks like a snake tongue. BUT if you are running very low pressure tubeless - when you hit that pothole hard there is no inner tube rubber and far less air to cushion the impact. In short… your lovely light and more vulnerable carbon rim is far less protected and takes a far greater impact.
10) Too low road-tubeless pressures can also lead to the phenomenon that many cyclocross riders have unnervingly felt. Tyre ‘burp’. As mentioned above it is air pressure that keeps tubeless tyres onto the shoulder of tubeless rims. Reduce the pressure too much and on fast cornering (or hitting a stone even) the force of the tyre being pushed inwards can be high enough to momentarily push a section of the tyre inwards and away from the shoulder. This brakes the seal and causes instant and alarming deflation. Once you slow down you usually recover control. But not always. Do you need this?
WE PROVIDE GUIDANCE AS TO RECOMMENDED TUBELESS TYRE PRESSURE WITH OUR WHEELS.
11) Perhaps most annoyingly there is a slew of new tubeless technologies that are designed to get round the design inadequacies of road tubeless. Annoying because they are based on trying to reduce the inherent design flaws of road tubeless without acknowledging that they are fundamental flaws.
For example hookless road rims: low pressure can lead to rim edge damage - so some brands rim edges are now made chunkier to reduce the chance of such damage - but as a consequence they have no traditional bead hooks. Bead hooks perform a vital role: They keep tyres from exploding off rims. So if you buy these “hookless” rims you absolutely have to keep to incredibly low pressures.
We understand that some manufacturers will not warrant over 60psi. whilst thats absolutely fine for the great big tyres of and rocks that you’ll hit during MTB usage … how does it stand up to road bike applications. And let us be clear here. We do not sell Hookless Rims at K1.
We all like to experiment with tyre pressures a bit - we believe that most leisure cyclists do not have any clear picture that they could be risking their lives by running their tyre pressures just a bit incorrectly if they happen to have hookless rims- (especially if they buy 2nd hand without manufacturers guidance information.) Only a few years ago roadies were running 120-130psi and the major danger of going too high was you’d break your pump. Some ran tyres at 170psi even. Not advisable but the technology was solid enough to even protect these silly-billy’s. (Me being one of them in my old skool racing days!)
This is what has changed: We recently saw a guy who runs his hookless at 90psi and was pleased how low pressure that was. He had no idea that this risked his tyre blowing off whilst riding. How many people is this true for???
A similar new tech is tubeless rim liners. These are lightweight foam strips which fit inside the tyre and are designed to at least help you to limp home when your tubeless setup lets you down. Again a tech that seems to miss the point to us. If such failures are so common then surely the underlying technology is questionable. So just more expense, more mess, more fiddly! And just adds a bit more weight and a bit more rolling resistance to put a liner in. Not much perhaps but again just a few things that erode the very advantages that road tubeless makers lay claim to!
12) LAST AND NOT LEAST (AND THE ONE THAT WILL GET US SHOUTED AT) ……TUBELESS IS NOT NECESSARILY FASTER
AND if all the above was not enough - tubeless confers questionable tangible performance benefits to road bike users in our humble view! Other than a bit more comfort perhaps. But you'll likely be so stressed by then you may not feel it!
As road tubeless tech has been around a few years now the performance side is being more clearly established by independent testers - Where initially we all had to rely on the marketing claims of the makers alone.
What is very apparent is how minuscule the performance differences are between the fastest clincher and fastest tubeless. Less than 1 watt. (See Below.) Important for a national TT rider but for everyone else … and against all the tubeless downsides we’ve covered … we ask is it worth it?
And remember from above that there's often a politics here: Interesting that a manufacturer might claim their new tubeless variants to be faster than their old clinchers. But when independent analysts do the tests they conclude the opposite to be true. More Here
We’re not going into performance data here - we’ll just give the links. Suffice to say the fastest/lightest tubeless has a rolling resistance of 7.5 watts at 100psi and the fastest clincher 8.4 watts. (Corsa speed g2 tubeless vs Conti gp5000 clincher with latex tube. Source here is independent and very highly regarded. Jarno at bicyclerollingresistance.com).
OK, the tubeless is faster and will save the average rider about 0.3 per cent of overall power required to hold the speeds the tests were run at. 18mph from memory I think.
But the Bigger Picture question still remains so clear: Is the added cost often, doubtful gains, unpredictability, mess, safety concerns, precise setup requirements and ongoing checks etc of owning tubeless worth it.
On a 5 hour ride you might expect to arrive at your destination about a minute or so earlier riding the very fastest tubeless. If you get there!!
And that’s riding the notoriously flimsy Corsa Speed 2 tubeless at about £150 per pair which will last a few months and are widely reported to leak sealant during rides. Have a google. And you’ll need to put a latex liner in really if you’re running this tyre on normal roads rather than drag-strip TT courses. Ouch .. there’s your 1 watt advantage gone.
The comparator is the Continental GP5000 clincher with latex tubes. With full puncture protection and costing half the price and lasting twice as long too.
You’d be forgiven for thinking above that we hate Continental tyres with what we report about their tubeless GP5000TL! But we love Conti. The GP5000 clincher is in our view the best tyre ever made. So fast and yet so reliable .. and it punctures so rarely why do you need the grief of the (slower!) tubeless version. Just look on wiggle and merlin etc to see the customer reviews of the clincher.
So, Top racers will gain a few key watts from the very fastest tubeless and that may matter alot .. but if they have to fly or get a tyre burp or there £3000 wheels are corroding fast is it worth it even then. And how about for the rest of us.
useful articles and links
Dr Xav Disley, Aerocoach. Do their own independent tests
As do: www.bicyclerollingresistance.com
https://www.cyclist.co.uk/news/5702/which-is-faster-continental-gp5000-tubeless-or-clincher