Dave's road tubeless doubts

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This post deserves a TL:DR summary, which is: If you aren't super comfortable with road tubeless and willing to spend some time and expense figuring out exactly which combo works for you, and also willing to petentially suffer a reduction in the lifespan of your wheels, stick to tubes. With a whole bunch of data now showing superior rolling resistance with clinchers and latex tubes, that may be the best way to go in any case. The ability to use latex tubes is another bonus of aluminum rims. 

For mountain bikes, tubeless is mandatory. For cross, it has its challenges (which we've done a heck of a lot to help eliminate) but the benefits can be so profound that the juice is for sure worth the squeeze. For road, though Mike and I personally use tubeless, we haven't been evangelical. It comes with downsides, which we'll talk about here. 

A potential "do as I say and not as I do" instance

We've been observing and talking about spoke tension drop in clinchers for a couple of years now. Since I've done THE WORST job at tagging posts, it's hard to find all the posts on the topic, but these two posts from last spring are good examples. There were a bunch of forum discussions in the spring of 2014, but I can't even recall which forum they were on. We even made a video to show the effect last spring. 

Wheel Fanatyk has what might be the second best wheel blog out there, and they did a series of posts in the fall about this whole topic, including the outward splaying of brake tracks which we'd discussed in above-linked post called "Pressure Drop Follow Up." What they did in particular, for which I have huge appreciation, is measure a bunch of tires to find how tightly they will fit. Their whole methodology and execution of this is excellent. What their measurements reveal is something that anyone who's installed more than one kind of tire will already have known - tire bead circumference varies by manufacturer and model. 

They've also measured overall circumference of a number of different rims, but they haven't shown the more relevant tire trough and bead seat diameters (which are simple secondary measurements from what they've done and shown). The overall circumference is of little value in its own right as, for example, a Zipp 404 shows a large outer diameter, but 404s are known to be relatively easy to fit tires onto (perhaps too easy?).

In order to resist the higher inflation pressures of road tires, road tubeless tires need a tight fitting carbon bead. The carbon bead more or less doesn't stretch, which is critical to having the tire not blow off the rim, and thus to keeping your teeth in your head. In that respect, it works quite well, but at what cost?

Non-tubeless road tires have either wire or Kevlar beads (if you're reading this, you probably have Kevlar beads). You probably notice that your tires get easier to install over time, which is because the beads stretch a bit over time. This stretch reduces the constricting pressure that the tire imparts on the wheel. 

Compressive tire loads cause a reduction in the circumference of the rim. Wheel Fanatyk estimates a possible 1mm reduction in the circumference, and my calculation gave me an estimate of .1mm in diameter reduction, so they estimate a bigger effect but we're not that far off in the absolute. I based mine off of "the spoke tension drop is x, the thread pitch of a nipple is y, the spoke tension drop is equal to z turns of the nipple, therefore the diameter reduction must be..." The important thing is that we're both seeing the same effect, in the same direction, with reasonably similar magnitudes. 

Compression is bad for the wheel for several reasons. It takes more initial spoke tension to maintain the minimum necessary functional spoke tension. Compression changes the dish of a wheel. Compression puts stress on the rim that almost certainly shortens a rim's useful life span. 

At the risk of speaking against my book somewhat here, I have two road bikes in current use (one disc, one rim brake, otherwise more or less identical) and those four tires are all tubeless. It works fine for me, but on a scale of 1 to 10 in tubeless experience, I'm about a 643. So if you are willing to invest time and money into getting your road tubeless set up perfectly, knowing that it comes with the potential to compromise your wheels, then it may be worth it to you. Otherwise, tubes are your best bet. 


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  • Jack Mentink on

    I have been running tubeless clinchers on several different road bikes and wheels for the last 4 years. The first one were hutchenson intensive 25's which worked fine on my alloy wheels with sealant. I next switched to some chinese carbon 23 wide by 50 deep wheels and switch to schwalbe ones 23's which I found out were a much better riding and faster tire. Sold that bike and wheel and tires and got my next bike which was a Giant defy advanced 0, which I put some carbon avenger 25 wide by 38 deep clincher wheels on. Have been through two sets of Schwalbe one 25's which are very nice and smooth (run at 80-85 PSI). Overall I have been through four sets of tubeless tires and 15000 miles and No flats, that right None, Nada. Tubeless in general are sometimes a pain to get seated initially, but after being seated they are wonderful and seriously reduce flats. I love the ride from a wide Carbon wheel with 80-85 PSI on schwalbe One's (now Pro Ones). I will not go back to tubes.I was really want to get some rails from November, but unfortunately You guys have bailed from carbon wheels. I cant think of going back to running an alloy wheels on my road Bike. I still don't understand the reasons you guys gave for going to alloy only , Insurance, seriously? How come all the other wheel manufacturers still have carbon? You had such a trend setting product in the rail. It was great and reasonably priced for the technology. You guys are so smart and do all sorts of research and data on your products. Now you put together other peoples alloy rims. Its just so disappointing. Bring back some carbon and get back on the cutting edge.

  • Greg on

    Going to make this really simple . Have been running Schwalbe Pro Ones for a full year now . At just over 13,000k no flats ,not one. (try that with a tubed system !! ) Ride is buttery smooth and fast . Tires mount without tools . System is lighter than with a tube . Whats not to like here folks ???

  • harry on

    Rail 52s + Spec Turbo Cotton 24s + Vittoria Latex = FSRS (freakin' sweet racing setup)

  • Dave on

    Greg, First off, I'm not unwilling to consider that my response may have been too strong. My intent was to maintain a decorum in this venue which we've been fortunate enough to enjoy for over six years, and which I don't see anywhere else on the internet. People can, and have, yell at me, call me an idiot, say I'm wrong (even when I'm objectively not), whatever – to me. The particular issues I took with your second comment were:1. It was your second comment, which merely reiterated more strongly what you'd already said2. It entirely discounted issues with the particular product you represent as being perfect that three other commenters had identified. You can yell at me, call me names, whatever, but to be rude to other commenters (which I thought your comment was, in that regard) I won't tolerate. 3. I've also needed to cut a Pro One off of an AX Lightness rim for a local customer, and directly know of several other similar issues with other rims. As for your free speech angle, it's off base. First, this is my company's site. We have never, not once, edited/moderated/deleted any person's comment here, ever. We owe absolutely no one any right of free speech in this forum. It is a courtesy that we extend in the spirit of fostering reasoned discussion. The tone here is, from my perspective, unique in that regard. And to compare what well and truly may be the most speech-permissive corporate site on the internet with what's going on in the US right now is just wrong. Do you seriously think Jack Mentick's comment would see the light of day on any other company's website? I do not, yet we welcome that kind of discourse because we learn from it, and it allows us to further articulate our perspectives. Jack and I differ in our perspectives on carbon, but I've learned his perspective which is valuable to me and he's learned mine which I hope has some relevance to him. In any case, the greater number of people who will read both comments but not respond get to see both sides. That's a substantially different scenario than what I perceived you to have done.As for my comment being rude or nasty, I'll leave it to others to judge that for themselves. I meant it as a courteous course correction to the established mores of this venue. We've almost certainly never been as cool as you thought. I've spent my entire life not being cool, made peace with it pretty early on, and have moved on. If you're looking for cool, there are a thousand sticker brands that love to talk about how rad things are. Cool just isn't us.This blog is the annual equivalent of a nearly 200 page book. It's a huge amount of work, and represents a ton of research and acquired knowledge, and most importantly it is an incredibly sincere effort to help people learn and get more out of their cycling purchases and experiences. Do we fuck up? Sure. You could pave highways with the number of typos, for one. But we always have respect for the reader, and his or her intelligence, at the forefront. Some (but not a conclusive list of) things for which you can thank us, in whole or in part, are:1. Pervasive wind tunnel testing with actual results. When we first did it, it was unheard of for a brand of our then-size (and even our now size) to do that.2. Testing against relevant competitive benchmarks rather than wheels which don't represent legitimate comparisons. No one did this before we did. 3. Testing alloys versus carbons, even at the risk of showing carbons not to hold the aerodynamic advantage they were and are broadly assumed to have. No one does this even now because it profits them to have people believe a bigger gap exists than what is there. Do you know how many emails we've gotten letting us know that people bought or built wheels not from us, based on info we'd provided, and to some degree or another thanking us for the information? 4. Comparing the aerodynamics of bladed versus round spokes.5. Comparing the aerodynamics of disc bikes to rim brake bikes.6. Unprecedented work on testing tubeless systems, particularly in cross but also in road.7. Heaps of information about rim and wheel stiffness.8. Just general honesty. For all of this info and, hopefully, entertainment, we ask for nothing in return. You don't have to be a customer to read or comment (I don't know if you are or aren't, I assume you aren't), you don't have to pay or look at ads or anything. But we do reserve the right to maintain a tone of respect among the audience, which I thought you'd breached. Again, I'm willing to be wrong, and if you're a committee reader, you knew that already. Dave

  • Greg on

    Sorry Dave Forgot about the new America where freedom of speech is now frowned upon . Thankfully Canada still allows for it .Geeze never figured I would get such a testy response to a few simple words . Enjoyed your blogs and business mind up until now :-( Super disappointed in you nasty response which is totally uncalled for . Its now loud and clear November is very far from being as cool as I had thought . So sorry I liked November , so sorry for liking tubeless !! Really just blown away by your rude words .



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