KNOWS NOTES – FITTING TUBELESS ROAD TIRES
The adoption of tubeless road tires and wheels for many cycling enthusiasts has not been easy.
Personally, I love the performance benefits tubeless brings me. More comfortable rides, better handling, lower rolling resistance, and almost no flats top my list. At the same time, I know there are many issues that cause some of you to come to hate tubeless and never know any of its benefits.
From what I can tell, loving or hating tubeless – and I don’t know many people who fall in between – is largely determined by your experience installing and maintaining tubeless road tires.
If you can get comfortable setting up and running the right combination of tubeless road tires and wheels, then you’ll love the benefits road tubeless gives you. If you can’t, nothing will overcome the dislike you develop trying to adapt to tubeless or the fear of dealing with a tubeless flat out on the road.
Yes, we can blame the industry for “hyping” technology that’s not ready for roadie time without first establishing standards. The reality, however, is that “standards” in the cycling world and in many other industries only come after years of adoption, if at all, are usually created in rather messy ways.
When one or two companies have a dominant share of the business, they use their market muscle to set the standard for what is acceptable design, performance, safety and other levels that smaller players follow. They will often dominate the standards issuing bodies or see those bodies adopt whatever levels they set. Helmet safety standards are a shameful example of this.
If there are no dominant players and no leaders appear to be emerging, years of negotiation between these competing players typically take place as part of the standards-setting committees they sit on. They are forced to work together to agree to some standards they can all meet to grow their business and have their individual investments pay off. This is what goes on in the cycling tire and wheelset market.
There are about a dozen sizeable companies making tubeless-ready road wheelsets and nearly as many, mostly different companies making tubeless road tires. So, we’ve got two fragmented sets of players that depend on each other to some degree for the ability to bring tubeless love (or hate) to road cycling enthusiasts.
None of these companies are in a position to dictate standards. So the discussions at cycling’s ISO and ETRTO standard’s setting committees continue at a speed that’s been way behind what is now two or three generations of new road tubeless wheelsets and tires.
It does me little good to blame the industry or wait for them to set (and follow) standards through these organizations. My goal, as it says at the top of every page of this site, is to figure out “What Cycling Gear to Get Next and Where to Get It” and share that with you.
My recent exchange with Alan, an In The Know Cycling reader, set me out on one of those “figure it out” challenges after he filed the following comment on my post The Best Tubeless Tires.
I found it impossible to mount the Conti 5000 TL on Mavic Kysirium Elite UST wheels. My local bike shop techies who are extremely experienced and professional failed as well. Even though a Continental rep at RideLondon registration in August assured me that they would fit, I have now received a message from Continental stating that the tyre and wheel are incompatible!
Luckily my supplier has agreed to refund on the unopened tyre but not the attempted mounting one. So I am now left with an expensive tyre of no use to me and non-refundable; thanks Continental.
I didn’t immediately approve Alan’s comment (all first-time posters have to go through “moderation”). I was surprised by it (I’ll explain why below), wanted to learn more about his experience, and then add an informed response to his comment.
Was this incompatibility Conti’s fault, as Alan’s comment concluded? The Mavic UST or Universal System Tubeless had been heralded by Mavic and the cycling industry press as “easier to use and safer than existing tubeless systems” when it was introduced in 2017.
While not dominant in the wheelset industry anymore, certainly Mavic is well respected for the volume and quality of wheelsets they build, if not for their technology leadership. They were clearly attempting to set a standard with UST and hoped other wheelset and tire companies would follow
Further, this Conti tire had already been flagged by ENVE as one that shouldn’t be used with their hookless rimmed SES 4.5 AR and 3.4 AR disc wheels.
The Continental Grand Prix 5000 TL was the tire I had recommended as the best tubeless tire. Maybe I had it wrong? If so, I wanted to know that and get the word out to all readers.
I asked Alan to tell me more about the problems he’d had. He sent me the following helpful background about his experience and the photo you see at the top of this post.
I spent a hour at my local bike shop a couple of days ago trying to fit the tyre. I had already had several goes myself using the stretching the slack and finishing at the valve, also with tyre levers. The chaps at the shop are much stronger and have fitted many more tyres as me but hit the same problems as me. The tyres bead is far too tight and the best achieved as to have about 6” of rim left to go on.
He also sent me a copy of the email he’d received from the Continental Bicycle Tyres UK rep.
Hi Alan, If you could return them to your place of purchase for a refund, that
particular wheelset will only run with mavic ust tyres, this is down to
mavic’s design that does not comply with the etrto standard and nothing we
can do about it. Kind Regards, Rich
Oh, this was getting ugly, at least by polite British norms. Conti blaming Mavic for not living up to ETRTO standards? Yet Mavic is one of the chief funders of the ETRTO bicycle standards section and cites ETRTO in the size of all of their rims, including Alan’s Ksyrium Elite UST wheels (“ETRTO size: 622x17TC ROAD”).
This was getting uncomfortable for me. See, in addition to recommending the Continental Grand Prix 5000 TL, I had also picked the Mavic Ksyrium Elite UST wheels as the Best Value in my Best Road Disc Wheelset Upgrades post and had called the ENVE 4.5 AR Disc wheelset the Best Performer in my Best Carbon Disc Wheelset post.
How could I recommend all of these if they didn’t work together?
Related: Click to read my latest review of The Best Tubeless Tires
The (Second) Experiment
I reached out to my friend Don who had a set of the same Mavic Ksyrium Elite UST wheels that Alan was struggling with. Don had come to hate tubeless and had given up on these wheels. He lent me his front wheel. (His back wheel had been trashed after he hit a pothole while riding at low pressure).
I also asked Alan if he was using a 25C size Conti tire to make sure I had the same combination he and his shop had tried to mount and that the Conti rep said were incompatible. His response added more context:
Hi Steve, Yes 25c tyres. I use Conti 4000 clinchers on my Zipp 303s and I am a big fan of their durability, puncture-resistance and grip. That’s why I wanted to use the 5000 on my Mavics. I had no confidence riding on the supplied Mavic tyres’ grip, especially after a slide off on a bend that the Conti’s would have handled easily.
I am hoping that I can find an alternative such as Vittoria or Specialised that can fit these wheels. My local bike shop will help me with this and their fitting so should avoid wasting money on other no hopers!
This got me thinking. Why don’t I do an installation test with a few different tires and wheels, including the ones Alan had tried, and see what happens. I did a similar experiment in my first review of the best tubeless tires that had included the Mavic Comete UST wheelset, a deeper, wider carbon one and the same Yksion Pro UST tubeless tire that came with Alan’s Ksyrium Elite UST wheelset.
During that first experiment, I had successfully if not easily mounted three other tubeless road tires – the original 25C Schwalbe Pro One, a 28C Maxxis Padrone TR, and Zipp’s Tangente Speed RT25 (25C) along with the much-adored Conti GP 4000 tubed clincher on the Comete UST rim.
When I reviewed the all-around, carbon Mavic Cosmic Pro SL UST wheelset (here), I had also successfully mounted and tested that wheelset with the Zipp Tangente Speed RT25 (tubeless) and the Conti GP 4000 (tubed) tires.
For this experiment of the Mavic Ksyrium Elite UST wheelset that Alan had tried to mount the Conti GP 5000 TL on, I grabbed both a new and used 25C size Conti GP5000 TL to try and a Zipp Tangente Speed RT25 tire that I had mounted successfully on the other UST wheels.
I also pulled out new 25C and used 28C sizes of the latest generation Schwalbe Pro One TLE (“Tubeless Easy”) tire that recently replaced the first generation Pro One tubeless which had been so popular. The Schwalbe rep had told me that the tire had been build to the emerging, yet still unofficial ISO/ETRTO standard for tubeless road tires.
Finally, to make this even more fun, I added a Zipp 303 NSW disc wheel that I had used in the earlier experiment and a HED Vanquish 4 wheel from a set I reviewed this summer. Both of these wheels and other all-arounds are compared in my Best Carbon Disc Wheelset post.
To briefly conclude an already too long story,
- Other than the Yksion Pro UST tire that Mavic supplies with each UST wheelset, I couldn’t mount any of the tires from Zipp, Continental or Schwalbe on the Mavic Ksyrium Elite UST wheel.
- All the tires, including the Yksion Pro UST, mounted rather easily on the HED and Zipp wheels.
When I say “I couldn’t mount”, I’m talking about the kind of mounting Alan and I attempted and that most enthusiasts would try in our own workshops when setting up a new set of tires or out on the road should we ever need to remount a tire after putting a tube in to account for an unsealable tire cut.
And when I say “mounted rather easily”, I’m talking about mounting the tire by hand within 30 seconds for most and 2 minutes with the aid of a tire lever at one spot on the rim for the Conti GP 5000 TL.
Interestingly, the Yksion Pro UST mounted within 30 seconds with no lever on the Zipp and HED wheels but it took me 2 minutes with the aid of a tire lever at one spot on the rim to get it on the Mavic Kysrium Elite UST wheel that it’s made for.
So why could I not get any tire other than the Yksion Pro UST on the Mavic Kysrium Elite UST while I could mount tires from several other brands on the Mavic Comete UST and Mavic Cosmic Pro SL UST wheels?
I don’t do science but I do do observation and deduction. And if you think that my use of the words “do do” before observation and deduction suggests this is all a bunch of crap, well I’m sorry. I’m generally skeptical of the claims I hear from cycling industry companies about how great their technology and products are so I’m left to do these kinds of experiments to figure things out.
Here’s how I explain the results of this experiment.
Wider rims making mounting tires easier – The Mavic Kysrium Elite UST wheelset has an inside rim width measured across the rim hooks of 16.7 mm. The other wheels in the experiment had inside rim widths ranging from 19 to 21 mm. In the case of all the rims tested, I clearly observed that the wider the rim, the wider the channel in the center of the rim.
The Mavic rim channel measured about 8.5 mm wide from edge to edge. The HED rim channel was nearly twice as wide at 16mm.
With a wider channel, more of the second bead of the tire is going to stay in the channel alongside the first as you mount it than it would with a narrower channel. The channel depth effectively reduces the tire rim’s circumference by enough to make mounting a modern tire where both beads can fit in that channel pretty easy. Without a channel or without being able to get that second bead into the channel, you’re not likely to be able to mount your tire at all.
Wider tire beads make mounting tires harder – The Continental Grand Prix 5000 TL’s bead is clearly the widest of the four tires tested. It measures about 4mm while the Zipp and Schwalbe (about 3.3mm) and Yksion (2.9mm) are narrower.
This is likely why it took me a bit longer and required a lever for me to mount the Conti than the others on the wheels with the wider channel. It may also explain in part why the Yksion went on the Kysrium Elite whereas the others couldn’t. I say “likely” and “in part” because, while I can’t quantify it, each tire’s bead stiffness and profile in addition to their widths seem different enough to have some effect on how easy or hard the mounting was. At least that’s what my thumbs were telling me.
I don’t think, however, that the bead width, stiffness or profile was as big a contributor to mounting as was the rim channel width. And, I would suspect the bead design is driven by getting the tire to seal and stay in place once on the rim than getting it on that rim in the first place.
Wheelset depth, tire size, tire age all matter little – Shouldn’t it be easier to get the same tire on a shallower rim as it doesn’t have as far to go over the edge of the rim? Shouldn’t a wider tire or an older one be easier to mount on the same rim because they have more slack either because of their size or being a bit stretched out due to their age?
Apparently not. Rim beds and channels typically sit at about the same depth relative to the top of the rim wall regardless of rim’s overall depth. And size or age doesn’t appear to make for any more room or stretch.
A UST designation is not important, at least to the ability to mount a tire – Despite Mavic’s UST claims, I haven’t found any significant difference mounting UST vs. non-UST tires on UST rims with the exception of the Ksyrium Elite UST rim and UST tire combination. While we can debate some of the other claimed benefits of UST, making mounting easier wasn’t a significant or even noticeable benefit of UST in my experiments. In my first experiment, I actually found it took longer and more tire levering to mount both the UST tire and non-UST tires on the Comete UST wheel than it did to put them on the Zipp.
Either way, to Alan and the rest of you that own the Ksyrium Elite UST wheelset, I would suspect the Vittoria or Specialized or other current 25C tubeless road tires may not easily fit on your wheels.
That said, I don’t think the Yksion Pro UST tires are bad. In my ride testing, I found they were are a big improvement over the prior generation of non-UST Yksion tires.
What Else Matters
While mounting a tubeless tire is a make or break consideration to even consider tubeless, if we were to choose between tires based on this alone we’d be missing a lot about what makes some tubeless tires better for you than others.
There other installation considerations – how easily does a tire inflate on the rim, how well does it seal, how long does it hold air? I answer these questions in the experiment section of the tubeless tire review I’ve referred and provided a link to above.
You’ll also find explanations of the five performance criteria that matter most in choosing between tubeless road tires in that review. In no particular order, they are
- Rolling resistance
- Puncture resistance
- Road feel
And then, of course, there are price differences between tubeless tires that will help you choose between them.
But, if we were to choose only between tubeless road tires for the above reasons and not consider how well a tire works with your wheelset together, that would be a big mistake as Alan and I, unfortunately, found out.
Beyond the difficulty of mounting a tire, how well the tire bead works with the rim hook determines how well it seals and holds air. And, as I mentioned earlier, some tubeless tires aren’t recommended for use with certain hookless rimmed wheels.
You should also pick your tubeless tire size knowing your rim width based on whether you prioritize for comfort, handling or aerodynamics or some combination of them. I wrote this post about that subject for tubed clincher tires a few years ago but it applies equally well for tubeless ones.
Recommending Tubeless Road Tires and Wheels
Some of you may be wondering: How can you recommend a tire like the Conti GP 5000 TL and wheels like the Mavic Ksyrium Elite UST or ENVE 4.5 AR that don’t work together?
Well, I’m recommending specific tires and wheels separately rather than in combination. I have also written, as in the case I mentioned just above, about the importance of considering tires and wheels together and given you some sizing if not product recommendations on those combinations based on your priorities.
In the same way, I’ve also recommended how to choose what type of wheels you should consider (e.g. upgrade alloy, carbon all around, aero, etc.) based on your riding profile, goals, and budget. You can see that post here.
All of that said, I know there are some tubeless tires and wheels that don’t work together. While I can’t check out every or even most combinations, I will go back through my tubeless tire review and add some specific recommendations about which tires I know don’t work with specific wheels or categories of wheels.
Hopefully, that will help those of you like Alan avoid the hassle he’s gone through and make better decisions from the start.
Share Your Experience
To help me and your fellow road cycling enthusiasts with this, I’d love to read about your experiences installing and maintaining tubeless road tires. You can use the comment section below to tell us what’s worked or not worked for you.
Answers to these kinds of questions would be great.
- What tubeless-ready wheels and tires do you use?
- How long did it take you and what techniques did you use to get your tires on your wheels?
- Did they seal with a track pump or did you use a compressor?
- How much sealant do you put in? How much pressure do you lose between rides?
- What kind of sealant do you use? How often do you top off or replace your sealant?
- Have you had a puncture that didn’t seal on the road? How did you deal with it?
- Do you love or hate tubeless? Why?
And lastly, if you haven’t tried tubeless yet but are thinking about it, tell me what questions you need to be answered to help you make a decision.
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That’s it for now. Thanks for reading and supporting the site. To keep in touch with what I’m posting and your fellow roadies are commenting on, use the popup form to get an email when new posts come out and the icons at the top to follow me on Twitter, Facebook, and Instagram. There’s also an icon you can click to get posts sent to your RSS reader.
Thanks and enjoy your riding safely.
Originally published: October 30, 2019
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