Robert Thru Axle bob-thru-axle close

Sometimes with innovation there is a sacrifice with some associated items becoming obsolete. Thru-axles are a perfect example of that. They are a stronger and offer more precise wheel to frame interface and have become standard on almost all mountain bikes and now some road and cross bikes as well. However, with this came the challenge of mounting specific racks, trailers, and even using your bike on a trainer. The Robert Axle Project has been offering some simple solutions that lets you use your more modern bikes with formerly incompatible trailers, carriers and trainers for some time.

Now, in an effort to make it easier to figure out exactly what you need for your ride, they have a new site and axle finder to guide you on your way…

Robert thru-axle-project

Tired of having to ride your old beater that you’ve only kept in order to yank the kids around in the trailer? The Robert Axle Project’s 12mm thru-axles are a simple over built design that allow your bike to perform more parent and adventure duties alike. Top left is their 12mm thru-axle for BOB trailers. To the right of that is their “Yoke” thru axle, bottom left is the more traditional that will fit many cargo and child trailers, and bottom right is the trainer friendly thru axle letting you use practically any bike whose wheel will fit.


They are easy to install requiring only a 5mm hex wrench you insert into the collar’s hole to torque it down. They come in just about every configuration you can imagine including axles for mountain, road, gravel/cross, and even up to a 12 x 197mm fat bike size. They even make just a standard thru-axle for those that may need a sturdier setup than what came stock on their bike.

Now, their website has a great “Fitment Selector” that breaks it down by your attachment needs, type of bike, bike brand, and rear hub to help you narrow it down.


  1. Happy to see Robert Axle get some press. I used their BOB axle for my Great Divide tour last year and it was awesome to combine my thru-axle equipped Specialized and BOB trailer. Good stuff!

  2. Love the idea. Just bought a Kurt adapter for my road disc and it requires a crescent wrench to install/remove. Talk about slow wheel changes! That said, I tried their website and it seems to be broken as I can’t find an axle for any config. Note to Robert (if you are looking), let me put in my bike and then show me the axles available instead of the way the finder currently works. I may just buy more than one if I can see the options at once.

    • David – The full array of axles is quite confusing, that is why we have the fitment finder. On our previous site, customers would routinely order the wrong product (not their fault – it is just confusing). You can go to our “What Axle Do I Need” page that lists all of our products and walks you through how to choose the right one. We currently have axles for: Hitch Mount Trailers, BOB Trailers, Yoke Mount Trailers, Bolt-On, or Trainers. Or shoot us an email, too.

  3. @David. Thanks for the feedback. Please try the Fitment Selector again, it’s working for many as we’ve tested it for a couple weeks now and we’re receiving good feedback on it. Send us an email so we can get more details as to what might be causing the issues.

  4. The Topeak Journey trailer is the best on the market at the moment but RAP don’t make an adapter for it yet.

    Lucky for me all my bikes are standard rear QR.

COMMENT HERE: (For best results, log in through Wordpress or your social media account. Anonymous/fake email comments may be unapproved or deleted. ALL first-time commenter's posts are held for moderation. Check our Comment Policy for full details.)

This site uses Akismet to reduce spam. Learn how your comment data is processed.