Monday, December 9, 2013

A Compendium of Tubeless Crr Results (plus getting up to date with some Vittoria and Specialized results)'s been awhile since I posted.  Sorry about that...but, after setting up a wheel for road tubeless as a part of the last post on the Schwalbe Ironman tires, I decided to try to get my hands on as many road tubeless tires as I could to see if there were any "gems" in the bunch.  In the past, the road tubeless offerings all tended to have less than stellar Crr results (mostly due to the butyl air barrier layers applied), but the Schwalbe IM offering showed that there might be some road tubeless offerings finally getting their Crr down there.  So, to start, here's how they stacked up, with a Continental GP4000S (latex tube) in there for comparison:

 Now then, as you can see, some of those tires compare favorably to the "benchmark" Continental GP4000S, but I also think it's important to keep in mind the measured widths.  In this case, all were measured on a Zipp 101 rim (internal bead width = 16.25 mm):

IRC Roadlite Tubeless 25C = 26.8mm
Continental GP4000S 23C (latex tube) = 24.7mm
Schwalbe IM Tubeless 22C = 23mm
IRC Formula Pro Light Tubeless 23C = 24.6mm
Hutchinson Galactik Tubeless 23C = 22.5mm
Hutchinson Atom Tubeless 23C = 21.8mm

As you can see, the IRC Roadlite Tubeless 25C measures nearly 27mm across when mounted on the Zipp rim...that's HUGE.  It makes for a great road/training tire, especially on the rear, and in fact that's what I've been using for that purpose for the last few months. For front tire usage, especially due to it's narrower width and aerodynamic features, the Schwalbe appears to be the best of the bunch.  The Hutchinson tires are narrow, but their Crr values are not so, it was my experience that the Hutchinson tires were significantly more difficult to mount (tight beads) than the Schwalbe or IRC tires. As for the IRC Formula Pro Light...that one is a bit of an enigma for me.  It's Crr is in the "decent" range (not great, but not horrible either) but it seems to be the most fragile of the bunch.  I used it for a short time as a rear tire and quickly suffered punctures large enough to not allow the sealant to work...and I think there are better choices for front, I'm not sure where I would actually prefer using that tire.  That's a bit disappointing really, because I think that it's unique latex based air barrier layer is the way to go for tubeless applications.

Tubeless Thoughts

After having ridden and played around with road tubeless offerings over the last few months, I've come to the conclusion that the purported "advantages" of running tubeless tires (with sealant) in road applications are really only realized if the vast majority of your punctures are from relative small items (i.e. 1mm or less).  Anything larger than that, and the air volume is too small and the pressures too large, for the sealant to effectively seal AND let you continue riding...with cuts or punctures larger than 1mm, you will most likely end up having to pull over and swap in a tube anyway.  So, if most of your problems with flatting are due to things like goatheads or "michelin wires", then tubeless with sealant is a really good way to go.  If you instead have problems with things like "pinch flats" (from hitting sharp edges or objects) you can actually get a significant improvement in performance just from using latex tubes and/or larger width tires.  Sure, latex tubes take some unique setup considerations for reliable use, but they're really no more of a hassle than setting up a tubeless tire using sealant...and in some ways they're easier on a day to day basis.

Vittoria and Specialized Results

Over the past few months, I've been testing some tires for Greg Kopecky and for inclusion in some review articles he's written.  An example is seen here ( Listed below are some additional tire results that I'm adding to the overall Crr spreadsheet linked to in the upper right of the blog.


  1. What type of tubes were used for the 2nd part of testing "Vittoria and Specialized Results" ??

    All latex?

    -Tom (not "unknown"!!)

  2. One more thing -- you wrote "latex tubes take some unique setup considerations for reliable use".

    What are those issues?

    I've used latex tubes a few times ... one thing I've noticed, is when they puncture, they deflate *very* rapidly compared to a butyl tube.

    Also, my latex tubes in service for more than a few months, acquired a dimpled appearance, which was unsettling.

    -- Tom

  3. The main ones are: 1.) Excellent rim tape coverage [fiberglass reinforced strapping tape or Stan's rim tape work the best for me] since latex will "extrude" through any small opening, and 2.) making sure that NO part of the tube is under the bead of the tire before inflation to prevent it from "jacking" the bead up and escaping containment...which usually results in a loud BANG. Applying talc (put in a Baggie with talc and shake) before installing helps, along with going around the rim and pushing the bead back with your thumbs prior to inflation and "flicking" it if you see the tube not "seated" up inside the tire.

    Don't worry about the dimpling. That typically is a result of the tube expanding down into the rim bed. It won't cause a failure.

    1. Great, thx for sharing your experience! :-)

      My clincher rims are Campy (aluminum alloy) Zonda, and those have a smooth bed -- no exposed nipple holes -- so no rim tape is required.

  4. BTW, I find that actual punctures deflate SLOWER with latex tubes than with's the "escaped containment" that deflate quickly, and loudly. But, those are actually installation errors, and are completely preventable if you follow the tips above.

  5. Does anyone know if anyone outside Schwalbe has measured the Crr of the Schwalbe One tubeless?

  6. Hi Tom, could you tell us about day to day air loss with the tubeless set up? If I recall latex needs to be pumped up every day more or less (assuming you ride every day). Is this your experience, and how does it compare to a tubeless setup?

    1. IME, it ends up being between latex and butyl tubes...but, I check my pressure before each ride anyway since it takes all of 30s or so ;-)

  7. Hi Tom, You should test new gp4000s II 25 mm. In my test, it roll faster 3 watts than gp4000s 23 mm! Alban