Trailer Hitch Adapter for M12x1.25

(76 customer reviews)

$ 25.00

Robert Axle Project’s M12x1.25 adapter for Kid Trailers and Cargo Trailers are designed specifically to fit your Rad Power bike or Mahle/EBIKEMOTION Equipped E-Bikes. and allow attachment of any hitch-mounted trailer. These Hitch Adapters fit any trailer that has two wheels and a single point of attachment to the axle. This includes all the two-wheeled child, pet and cargo trailers such as: Thule, Chariot, Burley, Instep, Carry Freedom, and many more.

If your bike has a 12mm thru axle we make thru axle adapters that you can find by using our Axle Finder here.

Purchase our Rad Power Bikes Hitch Adapter for your bike. Share your stoke for cycling with your kids. Simplify your life by allowing quick and secure attachment of your trailer to your best and favorite bike. Enjoy the adventure.

In stock

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The adapter threads on to axles with an M12x1.25 thread.

The Robert Axle Project Trailer Hitch Adapter for Rad Power Bikes and Mahle/EBIKEMOTION Equipped E-Bikes and most other hub motor equipped Ebikes. Our hitch adapter for towing kid trailers and single-arm bike trailers is high quality and precisely machined. This includes all the two-wheeled child, pet and cargo trailers such as: Thule, Chariot, Burley, Instep, Carry Freedom, and many more.

Our hitch adapter is made of stainless steel and is incredibly durable.  It’s built to handle towing a fully loaded bike trailer. The Robert Axle Project Hitch Adapter helps trailer hitches fit more bikes. It easily clears hooded dropouts and other interfering dropouts. It is easy to install. Simply replace the existing non-driveside nut with our adapter, and attach the hitch that came with your trailer.

Our hitch adapter uses a 17 mm wrench to attach your hitch and precious cargo more securely than with other knurled adapters. When installing the hitch, the 17 mm wrench isolates and protects dropouts from marring and over-tightening that could ruin your bike’s frame.

If your bike has a 12mm thru axle we make thru axle adapters that you can find by using our Axle Finder here.

At Robert Axle Project we believe in enhancing the role of bikes in your life’s adventures. Expanding our immensely thorough catalog of thru axles for trailers, racks, trainers, and more, helps us do that.

Additional information

Weight .3125 lbs

76 reviews for Trailer Hitch Adapter for M12x1.25

  1. Patrick Foy (verified owner)

    Fit the bike perfectly.

  2. Holden (verified owner)

    Super easy, cheap, gets the job done.
    Worked with our Cougar 2 Chariot, and worked with our RadWagon 4, as well as RadRunner

  3. Alex (verified owner)

    This may fit other ebikes (not just rad power bikes). It fits my Ride1Up 700 series perfectly.

    Got this to attach a PetSafe dog trailer and it has worked great!

  4. Randy Gillet (verified owner)

    Super easy installation and a perfect fit on the bike. We can now use our RAD e-bike to pull the trailer vice my old mountain bike.

  5. Jonathan H (verified owner)

    This was the perfect thing to allow me to pull my Thule Chariot Cross two seater kids trailer! I’m very happy, and the installation was quick, and it’s awesome to be able to pull my kids with my Rad Power Bikes Rad Rover 6 Plus.

  6. Dana Wright (verified owner)

    Perfect fit for my ebike to add my dog trailer to the bike.

  7. Christopher Taylor-Davies (verified owner)

    Saved my trailer purchase from being an expensive flop and set me off on a carless future! Superb.

  8. MG (verified owner)

    So glad I saw this on a Radpower bike forum, I was at a loss how to attach a pull behind kid trailer (in our case we were given an old thule chariot “cheetah”) to my new Radexpand5. It’s annoying that Radpower themselves can’t just recommend this piece, since it’s essential to using a trailer, but whatever, liabilty bs! Also the customer service was so great and item arrived really fast!

  9. Tom S

    Very well made and easy to install. I thought I wasn’t going to be able to attach my Burley to my new e-bike until I found this. Thank you!!

  10. Denney (verified owner)

    I don’t have much to add to the other positive reviews except that this is a very nice piece, singular construction. Very happy to be able to use the chariot trailer with our runner plus.

  11. Mackenzie (verified owner)

    Easy to install, works perfect! Hooked my Thule Chariot up to my RadWagon 4 with no issues!
    So glad to have found this!

  12. Linda Kiker

    Hello Project people. Thanks to your knowledgeable chat staff I was able to make sure that before I bought the axle adapter I’d be able to attach my new trailer to my new e-bike. Yes all new to me, so much appreciated. It went on easily and works great. It’s currently in place and hauling vegetable harvests to food pantries and other food relief organizations all over Denver.

  13. Armin (verified owner)

    Works perfectly on my RADExpand 5! Thank you for the fast shipping!

  14. Ryan Riley (verified owner)

    This is exactly what I needed to hook up my Schwinn Prescott kid trailer to my RadRunner 1. Thanks!

  15. Adam (verified owner)

    I was grateful to the site to ask the specific model of ebike and trailer. Maybe I was lucky to have stumbled onto the right part straight away, but in the shifting market I’m glad for something better than Amazon’s laissez Faire attitude toward holding vendors to task on fitment etc. The part was a perfect fit and overall quite affordable. No issues with the part, trailer, or bike. I’m able to take my 4 (!) kids out on a single ebike ride now. Thanks RAP!

  16. JoAnna

    I use this with my rad wagon 4 to pull an older style chariot. assembly was quick and simple. Only require a few simple tools that most people already have. Discrete when not in use. 10/10 recommend if you need a “functional” axle/quick release type substitute.

  17. Steve (verified owner)

    Just a slam dunk. This little piece is the trick. Fit perfect. A small price to pay for the solution to the trailer dilemma.

  18. Lori Conley (verified owner)

    Bought for my Rad Runner Plus. So easy to place. I attached my Aosom dog trailer to it and it fits perfectly and holds the trailer well and easy to ride. So glad I found this – the other options I read we’re much more expensive and labor intensive

  19. Jared (verified owner)

    Have a Ride1Up Core 5 and an Instep trailer and this adapter worked great. The bolt on the bike hub was longer than this product planned for so even with the the flat washer from the bike and the one provided with this product resulted in a loose setup. Easily fixed by going to Ace and getting a couple extra flat washers. Once those were on, everything was nice and snug. Have used it a handful of times and haven’t had any issues

  20. Ben

    This worked great for our Ride1Up LTD e-bike to attach a Thule Chariot hitch. (It was suggested by Ride1Up’s support; this site should advertise the compatibility more loudly!)

  21. Mark (verified owner)

    Perfect fit on a RadRunner2. Clear instructions, easy installation. Remarkably inexpensive for a very well designed and manufactured piece.

  22. Trevor (verified owner)

    Fit perfect. And fast delivery

  23. Agathe Rivière (verified owner)

    I live in Germany and have been looking for months for an adapter to attach my kid trailer (Thule) to my E-bike. The bike brand even told me it was not possible to do so! Thule recommended me then to reach out to the RAP. The team answered my question (which piece do I need?) within a few hours, and my order arrived extremely fast. It fits perfectly and we’re having a lot of fun with the kids now 🙂 thank you!

  24. Ryan (verified owner)

    Perfect fit for hooking up our Thule Chariot to our RadCity Step-Through. Fast delivery and a great price.

  25. Dan McGeary (verified owner)

    Works great on my Rad Rover. I pull a pet trailer with my bike. Makes it really easy to attach a trailer to a rear hub motor ebike.

  26. Josh (verified owner)

    Worked perfectly to adapt my Radrunner 2 to fit my trailer

  27. Kyrke (verified owner)

    This product has been amazing. It arrived super fast, was really easy to install, and has worked perfectly. I’m not certain you could ask for more.

  28. Ken

    Fit my Ride1Up Cafe Cruiser perfectly to attach a Burley Bee trailer. Thanks!

  29. Chris

    Fits an Aventon bike perfectly.

  30. Darren (verified owner)

    Really well made and does exactly what it’s supposed to do.

  31. Tia (verified owner)

    Worked perfectly for my Bee Adventurer eBike. I’m now able to pull my Burley Bee bike trailer

  32. Laura

    Worked perfectly for my Rad Runner 2 and my run-of-the-mill trailer. Very simple to install. Fast shipping. Thank you!

  33. Jeremy

    Fits perfectly on my Propella 7S for my Thule Cadence 2 in case anybody is wondering if it works with Propella bikes.

  34. Mattias Jakobsson (verified owner)

    Worked perfect for my Thule cougar on a Cannondale Treadwell Neo 2

  35. Christine Robinson (verified owner)

    Bought this to attach my dog trailer to my rize electric bike. It is such a well made part and fit my rear axle. It really is just goddamn awesome! Jaxy and I say thank you so much! Arrived quickly as well.

  36. Tom (verified owner)

    Worked just fantastic for a RAD ebike.

  37. Gabriele (verified owner)

    Absolutely perfect for my Orbea Vibe with Mahle X35 motor.

  38. Kemp Sawtelle (verified owner)

    High quality and easy to install. I can now pull my grandkids in the trailer with my RadRover 5 ebike. Recommended.

  39. Marie-Joelle (verified owner)

    Perfect fit and fast expedition!

  40. MSB

    I needed the adaptor for my thule charriot cross to connect it to my Aventon PACE 500 electric bike. Very simple to install, works perfectly fine. It solved my problem.

  41. Blazej (verified owner)

    Solid and fits perfectly to BAFANG G120.250.DC and Thule stroller

  42. Sarah (verified owner)

    Arrived quickly, easy to install on my RadMission, exactly what I needed.

  43. Katie (verified owner)

    Arrived so quickly and easy to install. We have two radcity5’s and needed to hook up our Thule trailer. Just took it out for a maiden voyage and its very secure!

  44. Jay (verified owner)

    Does exactly what it’s supposed to; very solid and clear instructions. The company was very diligent about making sure I was ordering the right part, requiring me to confirm the bike I ordered it for. I should note that this not only fit my RadRover 6 as advertised, but my wife’s EBGO electric fat bike (Canadian manufacturer.) Shipping was very fast to Canada.

  45. Alex (verified owner)

  46. Josh (verified owner)

    Perfect for Radrunner and Burley D’Lite. Took about 3 min to install.

  47. Alissa Perry (verified owner)

    Arrived quickly, and is beautifully made. Very solid and simple to use! I know very little about bikes, but this little part was the key to being able to use our rad ebike with a Thule trailer. We’ve gone on many adventures already, and plan to do more! Thank you SO MUCH.

  48. Devon Powell (verified owner)

    Worked perfectly for my rad power wagon to be able to attached a standard bike trailer.

  49. Brian Agee (verified owner)

    This hitch adapter made it possible to add an Instep child trailer to a new electric bike purchase (the Townie Electrica 7D). The mechanic from the chain bike shop I had purchased this bike from had no idea how I might attach my kids trailer and so it was on me to learn/know what an experienced bike shop had not idea about. Luckily, I happened upon an article on reddit which brought me here. My family is now able to ride bikes to the local swimming pool this season. Thank you to Robert Axle for making our summer a blast! And thank you for the excellent customer service through the website chat.

  50. Brian (verified owner)

    Works flawlessly on my Aventon Aventure 2. I tow a Burley Bark Ranger and its super easy to attach

  51. Alex (verified owner)

    Saved my ebike experience. I though commuting with my kids was over before I found you.

  52. Chris (verified owner)

    Works well on the Specialized Globe Haul ST. Would be even better if it came in black…!

  53. Porter (verified owner)

    So happy with the shipping time and the ease of installation. What I’m most happy with is the process of automatic identification of what size I needed built into the website.

  54. Travis (verified owner)

    Perfect fit for Co-op Cycles CTY e1.1 electric bike, but website needs to be updated to correctly route to this product for that bike.

  55. Tim Sullivan (verified owner)

    Worked perfect for my Aostirmotor S07b 750 watt electric bike! Looked everywhere for a 12×1.25 axle extender for my pet trailer, thanks!

  56. Ron Bukta (verified owner)

    Fit perfectly and shipping was incredibly fast
    Pups thank you for getting them back on the road

  57. Pete (verified owner)

    Performs exactly as described. Be sure to have the correct size wrench or at least an adjustable.

  58. Jerri (verified owner)

    I got the correct adapter without know more than what bike I own! It is good quality and it came fast. Great customer service!!

  59. David (verified owner)

    Fits perfectly on my Radpower 1 electric bike, to fix Chariot Thule childs trailer.

  60. Doug Mochoruk (verified owner)

    Worked perfectly on my RadExpand5!!
    Ordered Saturday delivered to my door (in Canada) by Monday! Thank you

  61. Russell Groves (verified owner)

    I’m a Pedego Electric Bikes dealer in Wichita, Kansas. Used this with my personal Pedego Interceptor pulling a Burley Nomad trailer.
    Installation was very easy and the trailer pulls like nothing. I’ll recommend these to customers and install them on my rental bikes that are suited to pulling trailers.

  62. Mike (verified owner)

    Fit perfectly on my rad rover 5
    Quality product

  63. Susanne L (verified owner)

    The Axle finder, and person I chatted online with was very helpful. I was able to get the adapter that I needed for my pet trailer to connect to my Aventon Aventure 1 ebike.
    The adapter fits my bike perfectly, and was very easy to install. Safety is what matters the most when it comes to towing my fur baby, and this adapter seems pretty solid of good quality.
    Shipping was also fast, and got delivered in just a few days. Very nicely packaged too. I would highly recommend this company, and I myself will be a repeat customer if I need anything else in the future. Thank you! Now I can bring my baby fur boy with me on all my adventures!

  64. Pavel (verified owner)

    Works perfectly with my REI CO-OP e1.2. Really nicely made adapter!

  65. Amy (verified owner)

    Fit my Rad bike perfectly to pull our bike trailer!

  66. Erik Heuckendorff

    This product fit my Rad rover plus fine and works great. Would highly recommend this product.

  67. Mara (verified owner)

    Has worked perfectly with the REI Co-op Gen E1.2 bikes to tow a bike trailer with 2 kids ranging from 2-5 years old without any issues.

  68. Vegar (verified owner)

    Perfect fit on my electric bike. Solid build and surprisingly quick delivery all the way to Norway. Would give six stars if I could.

  69. Daniel (verified owner)

    Works perfect for any e-bike with the larger drop out!

  70. Pommels Quicker

    Works perfectly with REI Co-op Generation e1.2 and Burley Bee trailer. You just have to select “Bafang” for the bike brand.

  71. Jérôme (verified owner)

    Excellent for my electric bike from Décathlon !

  72. Bryce (verified owner)

    Fits perfectly on our V Volt Alpha S. The kids being pulled in the trailer are big fans 🙂

  73. Alex (verified owner)

    Works perfectly for aventon aventure 2 and Thule trailer !

  74. Mark Altenburg (verified owner)

    Exactly as need. I’m impressed with the fit and quality.

  75. Meghdad (verified owner)

    Work perfectly on the Specialized Globe Haul ST. Used it to pull a Burley Bee. Highly recommend!

  76. Casey (verified owner)

    Good product. Fair price. Fit a Schwinn Porter to an Aventure.2.

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