Tubeless-Compatible 650B x 42 mm

Tubeless-Compatible 650B x 42 mm

If there is such a thing, Babyshoe Pass is our favorite tire here at Compass and Bicycle Quarterly. It’s 42 mm width gives it great cornering grip, comfort and puncture resistance. The 650B wheel size offers nimble handling with wide tires. The Babyshoe Pass is named after an iconic gravel pass in the central Cascade Mountains, because it’s great on gravel, too. Virtually everybody at Compass and on the “BQ Team” rides more than 90% of the time on these tires.

The Babyshoe Pass is an obvious choice for modern Allroad bikes. Some, like the Cannondale Slate, already are equipped with 650B tires, and they can realize their true potential with a set of supple tires. Others are designed around 700C x 35 or 38 mm tires, but 650B x 42 fits nicely and provides more air volume for gravel, as well as more nimble handling for paved descents. It’s a win-win situation, as evidenced by the Bicycle Quarterly test bikes that were equpped with these tires (above).

Being intended for pavement and gravel alike, the Babyshoe Pass tire always was an obvious choice for tubeless. However, tubeless-compatible tires have a different bead, so this required a new mold. We first wanted to gain experience with our other tubeless-ready tires before we replaced the molds for the Babyshoe Pass. Now that time has come…
When we designed the new mold, we increased the size of the Babyshoe Pass by 1.5 mm to make it a true 42 mm wide on most rims. If you mount it tubeless, it will be a little wider yet.
Currently, the new Babyshoe Pass is in stock with the “standard” casing. Later this year, the Extralight version also will get the tubeless-ready bead and extra width.
Click here for more information or to order.

Share this post

Comments (6)

  • Edwin

    I have been learning a lot about tubeless set ups from your blog. Not that I would ever do it, what with the descriptions of slime and air compressors and all. But I still like reading about it.
    One question from this post: Why would these tires be a little wider if mounted tubeless?

    July 28, 2017 at 7:29 pm
    • Jan Heine, Editor, Bicycle Quarterly

      Setting up tires tubeless isn’t as bad as it sounds: I’ve mounted all my tubeless tires with a floor pump… The tires are wider when set up tubeless because the air goes into the spaces between the casing threads and pushes them apart. An inner tube forms a membrane that prevents this.

      July 28, 2017 at 7:35 pm
  • Jeff L.

    Great news! Many of my friends have already been running this tire tubeless but after a blowoff I was not willing to do it without the extre security of the tubeless bead.

    July 28, 2017 at 11:46 pm
  • Peter

    I do hope Panaracer will improve the leak-proofness of the side walls and/or their QA process. Had to resort to superglue to get a Jon Bon EL airtight, it kept popping leaks at those (molding?) ridges perpendicular to the rim.
    Otherwise these are a joy to ride, should keep me comfortable on the British roads in the next five days 🙂

    July 29, 2017 at 12:31 am
    • Jan Heine, Editor, Bicycle Quarterly

      We’re glad you enjoy our tires!
      Regarding the sidewalls, it’s a trade-off. It would be easy to add rubber to the sidewalls to make them more airtight, but this would also make them stiffer, heavier and less supple. So we are keeping the rubber to a minimum, and this can sometimes result in a tire that weeps a bit at first.
      We’ve found that Orange Seal works best for initial setup – it seals much better than other sealants. However, it tends to dry out quicker, too, so after the initial setup, we recommend Stan’s for topping up.

      July 31, 2017 at 10:29 am
  • Steven

    I was so happy seeing these on the Instagram… I’ve been holding off on my next order (need to replenish RTP too!) for these…but no EL yet. Hopefully the ELs arrive before snow!

    July 29, 2017 at 3:17 am

Comments are closed.

Are you on our list?

Every week, we bring you stories of great rides, new products, and fascinating tech. Sign up and enjoy the ride!

* indicates required