Tubeless-Compatible Barlow Pass 700C x 38 mm

First, I want to apologize that several Compass tire models are out of stock. Orders from our distributors in Europe and Japan have exceeded our expectations, and tire production has to be scheduled long in advance… The tires now are on a boat to Seattle. We should have all models back in stock toward the end of the month. Until then, we appreciate your patience. We’ll put up an announcement when the new tire shipment comes in.

That shipment also includes the new Barlow Pass tubeless-compatible tires. Not only did we change the bead to a tubeless-compatible one, but we also increased the size by 1.5 mm to make it a true 38 mm even on narrow rims. The photo above shows a prototype. Mounted with a tube on a narrow rim, it measures 37.5 mm. On a 30 mm-wide rim and mounted tubeless, it “grows” to 40 mm. That puts it right in the middle between our 35 mm Bon Jon Pass and the 44 mm Snoqualmie Pass. The new Barlow Pass is another great addition to the Compass range. If you want to run your tires tubeless, it’s definitely worth the wait.

Click here for more information about Compass tires.

About Jan Heine, Editor, Bicycle Quarterly

Spirited rides that zig-zag across mountain ranges. Bicycle Quarterly magazine and its sister company, Compass Cycles, that turns our research into high-performance components for real-world riders.
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34 Responses to Tubeless-Compatible Barlow Pass 700C x 38 mm

  1. Peter says:

    I love riding the Jon Bon Pass (EL) tyres tubeless, but these are a rather close fit with 45mm (Velo Orange) mudguards. Any chance that the next iteration of Stampede Pass will be tubeless-compatible too?

  2. Rod Holland says:

    Jan, sounds like progress. A perhaps perverse question: do you have any of the older-design Barlow Pass tires in stock? If so, how do we go about order those? I ask because I am very fond of the original Barlow Pass, and prize their ability to be changed bare-handed, on the road. I’ve encountered the tubeless-ready beads on a couple of other Compass models, and found them a little rebarbative at first (although I’ve gotten used to them now). With the Barlow Pass soon-to-be-if-not-already transmogrified, I’d buy a couple of the older design if I could (needless to say, for use with tubes). Please advise if this is still possible.

  3. Rider X says:

    THANK YOU!!! I typically run Barlow Pass tires on my daily rider/commuter and have been quietly praying for this this upgrade for a while as I run tubeless on other bikes and like it. I was even thinking of moving up a size to the Snoqualmie Pass tires, but now I can go tubeless without altering my setup (I was going to need new fenders to get the proper clearance). Just in time too, as I am about to hit 7500 km on my Barlow and I don’t think they will last too much longer. Good thing I have been rotating them as I can replace both without guilt!

  4. John Thurston says:

    Is there some molding mark or distinction the unwashed masses may use to distinguish Barlow Pass Mk1 and Mk2? When I’m rooting around in my tire stash five years from now, and pluck out a Barlow, how may I distinguish the versions?
    I realize I could mount it on a rim and ride it. If it blows off on a bump it probably wasn’t tubless-ready. I’m hoping there is a simpler way.

  5. Bill Gobie says:

    How do you increase the size of a tire? Did you have to build a new mold?

  6. igxqrrlSam says:

    I (and, it seems, many others) really value the work BQ did on wide tires and supple sidewalls. Most of my road bikes are now on Compass tires.

    I’d love to see a similar analysis done for tubeless vs. tubed tires. From what I can see, the hype is strong for tubeless, but based on my experience with MTB tires I’m guessing it’s largely unwarranted.

    • We are working on that. One undeniable advantage of tubeless is that you don’t risk pinch flats any longer. But on pavement, most of us run tires wide enough that pinch flats simply don’t happen any longer. On gravel, it’s a different matter.

      As to the speed advantages, you replace a very supple inner tube with some liquid. Which slows the tire more? We’ll test to find out. As to comfort, again, with the wide tires we now run, the differences aren’t noticeable, at least for me. (I’ve run the same tires on the same bikes with tubes and tubeless.) The sealant will seal small holes, so a tubeless setup gets fewer flats. (You could probably add sealant to an inner tube, and probably would get the same effect, but we haven’t tried this.)

      The drawbacks of tubeless are the more difficult setup, the tighter tolerances it requires between rim and tire (there is no tube that reinforces the joint), and the need to replenish the sealant periodically.

      • Bob C says:

        I run Babyshoe Pass tires with tubes and sealant and I’ve been extremely pleased with the results. No flats in a long time. I’m not sure of there is a performance hit, but it seems to me if there is a performance penalty it’s quite small.

    • Peter says:

      I too would love to see a “proper” test. Last weekend I got a puncture that the sealant would not close when pressure got over 2 bar (29psi) and I had to mount a tube in order to ride with 3.3 bar / 48psi. Highly subjective, but with the tube mounted the ride seemed harsher than before. Mind you, this was in the UK, your choice of pavement is course, extra course or find-your-way-between-the-potholes 😉

      Mounting the JB Pass (EL) for the first time was an ordeal, first time ever I needed a bead jack to mount a tyre. Fortunately after a few months riding mounting was perfectly doable with just using my hands.

      • If you use tubeless-ready rims, make sure the bead is in the well (center of the rim bed) all around before you try to lift the last bit of bead over the hook. With supple tires, it’s easy for the bead to sit on the shelf in one place, which makes mounting very difficult.

      • morlamweb says:

        I, too, would love to see tubeless tires and wheels go under the BQ microscope. I’ve read quite a few anecdotes about tubeless but there’s precious little hard, BQ-quality information about them out there.

        Lightweight wheels with tubes and light, wide, supple, low-pressure tires already gives me excellent ride quality and speed, and I need only purchase better tires if I find a better option. In fact, I may buy a set of Rat Trap Passes, as they appear to be better still than my Schwalbe Marathon Supreme 50-559s. However, if I were to go tubeless, I’d have to buy new tires, of course, but also modify or replace my wheels; buy sealant; and perhaps a tire installation tool. Unless tests bear out that a tubeless setup has a marked advantage over tubes, I’ll stick with what I’ve got.

      • We are working on tests of tubeless performance. In the mean time, unless you get pinch flats, I’d stick with what you got! In any case, a more supple tire will give you much greater speed benefits than any potential advantage of going tubeless.

      • It’s interesting that at lower pressures, tubeless seems to be slower than a tire with tubes. On real roads, you may see reduced suspension losses with tubeless tires, but if anything, this suggests that any performance differences with tubeless will be very small.

  7. Distributor in Japan? Do you know where they will be available?

  8. Glen Stickley says:

    On the Compass web site for each tire size there is an overview page. It would be handy if on this overview page you could see if a tire was tubeless compatible or not. A “TC” in the title of tubeless compatible tires would work.

  9. Rick Thompson says:

    Jan – Encouraged by your research, I have just placed a deposit on my first custom frame. The plan is to build it for the 700C x 44 Snoqualmie Pass tires. I realize no guarantees in life, but are you planning to continue production of these for the foreseeable future?

    • We plan to continue producing all our tires, and the Snoqualmie Pass is a popular model.

      • Rick Thompson says:

        Great, thank you. If I may ask another tire question: A recently acquired Santana tandem came with 29 mm tires, we have been running 100 psi. Bon Jon Pass 35s would fit, but wheel loads are ~200 lb which is off the Berto chart. Should we get the ultralight or standard casing? What pressures would be safe to try? (Sorry, that was 2 questions.)

      • The Bon Jons are rated to 90 psi, which should be enough. I’d start with that, then reduce until the handling starts to feel a bit wallowy. Use the standard casing – the Extralights require about 10% high pressure, and you are already reaching hte max…

  10. Matthias Krogmann says:

    Distributor(s?) in Europe? You’ve mentionted 2-11 cycles in France, is there may be a source in Germany?


  11. Jim says:

    I’ve been running Baby shoe standard casings for a year now tubeless with Velocity Blunt SL rims and they work great. My only problem was not keeping the sealant full in the rear and had to run a tube to get home. But then inspected the rim and found cracks around the spoke nipples so it was a good thing to get that flat.

  12. Nathan says:

    Great news!

    Is there a chart somewhere showing the expected outer diameters of wheels with different Compass tyres installed?

  13. Stuart says:

    Does the tubeless model differ in weight from the previous model?

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