12mm Thru Axle for Trainer: 172 mm with 1.5 Thread

(51 customer reviews)

$ 54.00

Our Trainer Axle is designed to adapt your thru axle equipped bike with your on wheel trainer, such as a 1up, Blackburn, Cyclops, Kinetic, Tacx, Wahoo and many other trainers. Our goal is to fit the thru axle to your bike perfectly, so we minimize spacers and extra parts, providing a clean, high performance axle for your bike. Train, warm up and be race ready and fit for the season.

In stock

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SKU: TRA204 Category:


  • This Trainer Axle is designed to adapt your high quality bike to your on-wheel trainer. These are compatible with all the popular brands: 1up, Blackburn, Cyclops, Kinetic, Tacx, Wahoo and more.
  • Our first priority is building a precision thru-axle. Our axles fit into your bike as well or better than the stock thru axle.
  • The axle is installed with a simple 5 mm hex/allen key. The same tool that you carry on every ride.
  • The best part? When it’s time for your race or time to head outside, simply remove your bike from the trainer, remove the drive side axle end and go. Our axle is suitable for use on or off the trainer. Indoors or out.
  • Important: Before you order, make sure your specific trainer will accommodate the width of your modern thru-axle equipped bike. Measure your trainer at the widest setting and measure the outside width of your bike frame. Our the trainer axle ends will extend past your frame on each side.


Prop65 Warning icon

WARNING: This product can expose you to chemicals including nickel acetate, which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.



Robert Axle for Trainers replaces your stock 12 mm thru axle so you can use your bike on a trainer.

  • This axle is compatible with 1up, Blackburn, Cyclops, Kinetic, Tacx, Wahoo and many other on-wheel resistance trainers.
  • The true length of the axle shaft is 172 mm. Can also be run with the included 3mm spacer for 169 mm fitments. Please note: Thru-axle lengths do not equal hub standards. An axle has to be longer than the hub to fit in the frame. A 12Ă—142 hub does not equal a 142 mm long axle.
  • This axle has a 1.5 mm thread pitch.
  • The axle shaft and axle ends are precision CNC machined from 7075 aluminum, and hard anodized for rugged durability.
  • No special tools required. Design allows for installation or wheel removal using your standard 5 mm hex wrench.
  • Designed, built and quality tested in the USA. Proven around the world.


Need more information about how our axles work?

51 reviews for 12mm Thru Axle for Trainer: 172 mm with 1.5 Thread

  1. Carter

    Great product from these guys. Use mine all the time and also works well as an upgrade from the stock TA on pretty much any bike. Seems to have better tolerances than the DT Swiss one that came with my bike and eliminated the creaking that would occur due to DT’s slack tolerances.

  2. Danno (verified owner)

    I was a little worried at first that I would have to return my trainer. RAP had just what I needed. I printed out the guide and used it to cut out the guess work. I got the right one within days.

  3. Chris Kuhl (verified owner)

    Awesome product, very fast shipping. I was surprised when I couldn’t find a 12x142x1.5 axle for my Marin hard tail 29er so I could use it on my trainer. This jus the solution and works great, the quality is very nice, highly recommended.

  4. J black (verified owner)

    Works as advertised. Shipping was very quick, especially for the time of year the order was placed. Thanks.

  5. Pierre (verified owner)

    Ordered this axle for my Yeti SB4.5c.
    In order to fit the axle, I had to remove the lock nut on the drive side and add a washer.

    With this modification, I was able to use my Yeti on my home trainer

  6. Mike (verified owner)

    Robert Axle Project was recommended to me by the team at Raleigh for my Merit. What a perfect solution! The axle has been a great fit for my CycleOps PowerPro. Easy to install, and works wonderfully with both systems. There was a point where I started to doubt that a solution existed for the wide drop-out on the Merit, but this was perfect.

  7. DocWass (verified owner)

    Exactly what I was looking for! My new bike has 12mm thru-axles and came with a kit to change out the rear to QR drop outs so I could use it on the trainer. I didn’t want to hassle with changing back to 12mm for road riding and the 5mm QR drop outs looked like they would flex. Found these and initially thought they were a bit expensive but the reviews persuaded me to part with the money. The fit/finish is excellent and the bike fits securely in the trainer. The added bonus is I don’t have to change it back for road riding. Perfect!

  8. Shawn Chervak (verified owner)

    I searched on the internet then called Diamondback to confirm length and pitch. They recommended these axles over anyone else, which eliminated any doubt for their axle to work. It’s simple and perfect, works great with my trainer that I have left the axle in when I do head outside. Even with a recent puncture there was no more of an incovience in pulling the axle out to patch the tube.

  9. Logan (verified owner)

    Works great! Almost thought I had to return the trainer I purchased. Chart made it easy to make sure I got the right size!

  10. Chris (verified owner)

    Great Product MADE IN USA! Was bummed when I bought my new Salsa Warbird and couldn’t find a thru axle to fit my trainer. Salsa actually recommended RAP! Great company, in stock products, fast shipping= Happy customer!

  11. Patrick (verified owner)

    great product, only 4 grams more than the stock thru-axle bolt.

  12. Lee Waldman (verified owner)

    These guys are great. They had what I needed when no one else did. I received my product quickly, the price was fair and they are great about responding to questions. I wouldn’t hesitate to deal with them again when the occasion arises

  13. terry (verified owner)

    great product works well with my trainer – perfect fit for the bike ! delivery to New Zealand only took a week ! would definitely shop with again

  14. Joe Janney (verified owner)

    Great product. My wife and I both use our Wahoo Kickr Snap trainer with bikes having different axles. The Robert Axle Project axle allows us to quickly swap out our bikes without making changes to the trainer. My wife’s bike has a standard axle that fits with the rear axle equipment the Kickr Snap provides. My bike has the through axle that would have required me to buy a conversion kit from Wahoo at $80, then swap out the two different axle holders on the trainer when moving between bikes. I saw a note posted on Wahoo’s site about the Robert Axle Project and found this site and purchased the trainer axle that fits directly on the Kickr Snap trainer without the conversion kit. You should contact Wahoo and see if they would sell your product on their site vs. the conversion kit. This is a much better solution. Keep up the good innovative engineering!

  15. khanh (verified owner)

    Quality product, arrived very quickly and by using the print out to get the correct thread pitch, length it fit perfectly for my Pinarello Dogma F8 on the Wahoo Kickr Snap

  16. Brian (verified owner)

    I bought an axel for my 2017 Fuji Jari to pair with a Wahoo Snap Trainer. The installation was easy and it works perfectly with both the bike and the trainer. I’ve put about 200 miles on the axel so far and it works great. No complaints and I’d recommend it in a heartbeat.

  17. Curtis (verified owner)

    Good stuff! Perfect fit, clean look, does exactly what it is supposed to.

  18. Erik S (verified owner)

    Exactly what was needed, this fits on the trainer perfectly plus I can remove one side of it if I want to and just run it as a normal axle that fits flush to the bike. Better than the stock axle!

  19. Thomas (verified owner)

    Perfect fit for my trainer. Fit my bike like a glove too!

  20. Bob Grier (verified owner)

    12mm 172mm w 1.5 thread – Perfect fit (with the one washer that was included without my request) for my Wilier GTR Team Disc and CycleOps Fluid trainer. The Robert Axle Project team handled my pre-sale question quickly and the entire process was seamless. Thanks very much!

  21. Nathan Morgan (verified owner)

    Solid Product and very well made. Would like to see a captive washer rather than a free one so I won’t lose it, but then it might not fit on every frame. Bought the lightning bolt on axles as well. Nice ’80’s reference to boot. What’s not to like?

  22. Derek Morrison (verified owner)

    This is a great alternative to the thru-axle kit for the Wahoo Kickr Snap. I don’t know why Wahoo didn’t use this design, as it’s more functional. I can use the trainer on my bike with this adapter and then fairly seamlessly switch to using my wife’s bike (which has a standard quick release) on the trainer.

  23. Connie Petrick (verified owner)

    Have a Diamondback Airen5 Carbon and Mag Trainer. Bought the 12 mm thru axel; 172mm with 1.5 thread. It fit and worked perfectly. Great product and prompt delivery. Would definitely recommend to others with similar needs.

  24. ryan (verified owner)

    Good price, fast shipping. The axle selector is a great tool to find what you need. Axle fits and performs perfectly on my cycleops Fluid 2 trainer

  25. Noah Muse (verified owner)

    Great design and fixed my problem with ease! Cycleops doesn’t make a 1.5 thread axle for some reason, but it was easy enough to find RA Project. A much better solution and I can leave the axle in for off trainer rides too! Much improvement over my Kinetic converter I used on my old trainer (which was too long for my Fluid 2).

  26. Jason (verified owner)

    Purchased a new smart trainer online and i wasn’t too familiar with thru axel sizes on my bike and when I received my new bike trainer I quickly figured out that the thru Axel that came with it was not compatible with my trainer. Robert Axel Co. made it super easy for me to get this thru Axel. It showed up within a few days and fit great. Highly recommend.

  27. Scott A. Anderson

    Perfect fit. I purchased the similarly-promoted product from Saris, and the Saris product was unusable. After returning it, I ordered the Robert Axle and it arrived quickly and fit perfectly! Thanks for making a great product

  28. Stephen (verified owner)

    Exactly what I needed for my Fairlight Strael – fits perfectly, so problem solved. Great customer support too when I wasn’t sure what I’d need and they were quick to point me in the right direction.

  29. Shahn (verified owner)

    This axle works perfectly for what I need. I actually left it on the bike, since I always have a multitool when I ride, and it’s only slightly more inconvenient to get the axles off than a lever mechanism would be.

    Representatives were very helpful with support and confirmation that I was buying the right item. Shipping was fast. Would most certainly buy rom Robert Axle Project again.

  30. JH (verified owner)

    Huge improvement over the quick release-style adapter I had been using with my Wahoo KIKR trainer. This is a MUCH better fit. There’s a noticeable difference in how smooth the bike runs on the smart trainer.

    I also avoid the need to swap axles if I’m using the same wheelset. I already carry a 5mm hex in my saddlebag to remove the axle if needed. So I can pretty much take the bike straight from the trainer to the road. One less thing to do. Perfect.

  31. Pablo Roman Garcia

    Great product, super fast shipping and awesome buying experience.

  32. Javier Garcia (verified owner)

    It fit and works perfectly. The guide of how to choose the axle you need is very simple and after ordering it, the shipping was really quick to Europe.
    Highly recommended.

    Just as a constructive feedback, I would wish that you could choose the color of the “ends”. If it was just black it would look as nice as the original axle.

  33. Jacob (verified owner)

    Shipped fast, works great. I will definitely use this site again for my future axle-related needs.

  34. Todd (verified owner)

    This works great! I built up a separate rear wheel with a trainer tire and have had no issues using my MTB on the trainer. Happy.

  35. Mike (verified owner)

    Had to order a thru-axle for my bike in order to use the trainer I received for Christmas. Had no idea how to choose the correct thread pitch. RA Project’s axle measurement printout was just the right tool for the job. Once I had the thread pitch, length of available axles did not match my current axle – a quick e-mail to their service rep, and I had the right axle chosen. Thank you very much for being thoughtful and customer-focused!

  36. Douglas Einstein (verified owner)

    Great axle! Perfect fit. And, outstanding customer service!

  37. Kenny Fike (verified owner)

    Axle fit great and works on my Amazon trainer I bought so I can now exercise on rainy days. And I I leave the axle and trainer end cap on when I ride off-road with zero issues. Quality product.

  38. Keegan (verified owner)

    The online tool for identifying the appropriate axle is easy to use and ensured that I got the right fit immediately.

    Easy to install on my Ridley X-Ride and integrated perfectly with my Kinetic trainer.

    Simple. Well-made. Does exactly what it’s supposed to do. Can’t ask much more from a great product that’s also made in the US!

  39. CadPinarello (verified owner)

    Fantastic product that provides a durable axle to attach my road bike to either a wheel-on or Smart trainer. Works perfectly. Thank you.

  40. Phoebe (verified owner)

    I had a difficult time finding a trainer axle that works with my Pinarello & Wahoo Kickr SNAP, and the Robert Axle team took time to help me find the correct axle! The threads also fit really nicely into my bike which wasn’t the case with my old Traxle, which supposedly was the right fit for my bike but rattled a little. Thanks to Robert Axle for a great product & even better customer service!

  41. Marci (verified owner)

    Very easy to install and great that I can use it off the trainer. Excellent quality.
    The axle finder was extremely helpful and easy to use! Good price, good folks, made in USA…I don’t know why anyone would choose any other axle to buy!

  42. Stephen (verified owner)

    I found out about this site from a recommendation on an online forum. I just got a new bike with a thru axle and needed something to be able attach it to a Kurt Kinetic trainer. I have a smart trainer but I only use it during the Winter. I keep the old trainer around for use as a work stand or a quick workout on a rainy day during riding season. While this product seemed a bit pricy at first, it is of high quality and works perfectly. Problem solved!

  43. Dale (verified owner)

    Fit well and now I can use my trainer!

  44. Claudia (verified owner)

    amazing support, fast delivery to Austria/Europe, great quality product. will order again 4SURE

  45. Steve (verified owner)

    Beautifully made and sturdy. Works perfect on my old Cycleops trainer.

  46. Michele

    Les than a week to reach Finland. Beautiful made. Good instructions. Works perfectly on my Basso Palta and Cyclops trainer. Absolutely nothing to complain.

  47. Nick DiMauro (verified owner)

    Works perfectly with my Fairlight Strael 3.0. I use it to ride on my Wahoo Kickr Snap. Install is easy as can be. I was worried I would have to buy a much more expensive direct drive trainer which I did not want to do considering my Kickr Snap was only a year old. You guys rock!

  48. Doug (verified owner)

    Bought one for a Fuji Jari and a Salsa Warbird. Fit perfectly on the bike and with a trainer. Shipping was fast.

  49. NC (verified owner)

    Excellent Service- Fst delivery of the perfect part.

  50. Jason (verified owner)

    High-quality axle that fit perfectly on my Polygon S5 Disc road bike and allowed me to use it on my trainer without having to swap anything out when I take it outside. Speedy order processing and delivery and clear instructions.

  51. JF (verified owner)

    Perfect fit

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