12mm Rear Lightning Bolt-On Axle: For Cervelo R.A.T. with Derailleur Hanger

(30 customer reviews)

$ 80.00

Cervelo owners with R.A.T. thru axles: This axle will replace the R.A.T. axle found on all Cervelo R.A.T. equipped bikes. In addition to this axle we include our replacement derailleur hanger with with traditional threads. This axle combined with the replacement derailleur hanger will provide a complete threaded thru axle system. Our derailleur hanger matches the geometry and construction of the stock derailleur hanger in every way for crisp shifting performance.

Our Lightning Bolt-On thru axles offer the highest quality, simple, lightweight alternative to that bulky handle.

Learn about compatibility with Hexlox security systems.

In stock

Get 20% Off Lightning Bolt-on Axles With Purchase of Any Trailer or Trainer Axle! Discount Automatically Applied.
SKU: LIG623.C Category:


  • This axle is designed specifically to replace a rear R.A.T. axle on a Cervelo bike with included derailleur hanger.
  • Lightning is Better. Our front and rear Lightning Bolt-On axles offer a stronger, more durable, lower profile and lighter weight option to replace your stock thru-axles.
  • Low Profile. No more bulky handles to strike trail obstacles. Aerodynamic design.
  • Light Weight. Our axles are internally bored to remove unnecessary material without compromising strength. Our axle weighs 36 grams. Our axle and hanger weigh a combined 54 grams. Front and rear, our axle system saves a combined 58 grams.
  • Easy to install. Our matching front and rear Lightning Bolt-On Axles only require a standard 6 mm hex wrench for easy installation and removal.
  • Better Tolerances. Manufactured in the USA to the tightest tolerances using aerospace materials and CNC manufacturing. No longer will your axle loosen while riding.
  • Available Security. Learn about compatibility with Hexlox bike security systems.

This is NOT an axle for attaching trailers or trainers.



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.

Additional information

Weight 0.3125 lbs


  • This axle is designed specifically as a replacement a rear Cervelo R.A.T. thru axle. Included is our Cervelo R.A.T. derailleur hanger into which the axle threads. Our axle is a direct replica of Cervelo’s part number: DRH-WMN112. We do not believe in creating proprietary parts!
  • Our axle weighs 36 grams. Our axle and hanger weigh a combined 54 grams. Front and rear, our axle system saves a combined 58 grams.
  • The axle is precision CNC machined in the USA from 7075 aluminum and hard anodized for rugged durability. Our axles are built to the tightest standards in the industry.
  • No special tools required. Design allows for installation or wheel removal using your standard 6mm hex wrench.
  • Designed, built and quality tested in the USA. Proven around the world.


Need more information about how our axles work?

30 reviews for 12mm Rear Lightning Bolt-On Axle: For Cervelo R.A.T. with Derailleur Hanger

  1. Boris Vinitskyi (verified owner)

    exactly what I need! Fits perfectly to my bike cervelo s5 gen III

  2. William Simon (verified owner)

    Fit my 2018 Cervelo R3 perfectly. The install was easy, fit and finish top notch. I didn’t even have to adjust the derailleur. If you want to get rid of the RAT lever this is the way to go.

  3. Harold (verified owner)

    After getting my new cervelo I was having issues with a noise in the rear of the bike. Came to figure out under power the rat axle wasn’t secure enough. So after some looking I ordered front and rear axle replacement. Installed took about 15 mins with good directions and tools needed. Now everything this how it’s should be quite and looks good

  4. Charly Leporc (verified owner)

    Exactly what I needed for my S5 and get rid of the horrible RAT axle.

  5. Nathan Ansell

    Amazing axles. I didn’t need to replace my RAT axles but when trying to find a RAT rear mech hanger in the uk it was proving difficult with only 3 distributors available. This got me looking in to conversions, and I am glad it did. Gone with the lever for neatness, looks better, lighter, and more secure if leaving outside a coffee shop. So glad I bought these as the quality is great. Communication via email was prompt, informative and lighthearted too which was nice. Good work

  6. David (verified owner)

    Replaced the front and rear RAT axles on a Cervelo R3. Love the precisely machined threads, it gives a very confidence-inspiring, secure fit. Feels super solid on the bike, and no more wiggle room when installing the wheel. Makes it easy to align the brake rotors when a wheel is removed and replaced. Lighter weight and cleaner appearance is a nice bonus as well. Love these axles!

  7. Arron (verified owner)

    Replaced my Rat Axles on my 2019 Cervelo R3. Bike feels different, but can’t place what the difference is. Is it lighter? Is it stiffer? Is it both? Logically, for sure lighter, but can’t really tell by lifting it. The way it rides just feels better. If I end up getting at Aspero, these will be ordered the day I order the bike!

  8. Sean D (verified owner)

    As for the front axle, it feels far more solid (and hence safe and secure) than the RAT it replaces. However, it does require a suitable wrench to remove if I have a flat out on the road. Perhaps a lever to help get it loosened on the non-threaded end would be a help?

  9. Sixto H (verified owner)

    The material is awesome and looks really great. Also the fit was really good and it arrived in 1 week from USA to Canary Islands so that was a plus.
    Only thing: i didn’t find a video where it explained how to change it so i think that is the missing bit to make a 10/10 product.

  10. Wesley Ooms (verified owner)

    Great upgrade for my 2020 Cervelo S3 where they used the R.A.T system that must have been designed by a moron. I mean it’s a bolt and a nut. How complicated, flimsy and unreliable can you make it?

    I’m really happy with my Robert axles. A design that has withstand the test of time; a bolt and nut.

  11. JASON FLASHBERG (verified owner)

    Been struggling with creaks and disc brakes not aligning properly on my 2018 Cervelo R3. Thought it was the BB, the hub, rotors out of alignment. Finally realized it was the Cervelo R.A.T. Thru Axles. Replaced both the front and back with RAP Lightning bolt-on thru axles. Bike runs great and looks better. Installation instructions were spot on. I highly recommend this product.

  12. Stefan Schaefer (verified owner)

    Very fast delivery to Germany!
    Great product, super easy installation and quality 🙂

  13. Viacheslav Ovsienko (verified owner)

    Amazing product. I recomended all stars!!! All perfect.

  14. Michael Thompson (verified owner)

    My original R.A.T. axle stopped working. This design is much better. It’s lighter and easier to get on and off. It also seems stiffer than the Cervelo design and less issues with rotor rub.

  15. Robb Johnstone (verified owner)

    I thought it might be finicky to install but it was super easy. The derailleur hanger just swaps out easily with the old one. I’ve practise removing the wheel and yes it takes longer than a rapid axle but I get far more peace of mind knowing it’s firmly in place and that I can’t screw up when I’m out on the road. No problem keeping a 6mm hex key in my pouch. And the clean lines of this axle replacement are a nice bonus!

  16. Sean (verified owner)

    Perfect fit on my cervelo and great customer service.

  17. Janis (verified owner)

    Chose this product to replace RAT axles on my Cervelo R3 2018 after one of the RAT axles broke. So far I’m very satisfied with the product. Having replaced both – front and rear axles, I have to say that I’m more impressed by the rear one. Rear axle of the bike has a more complex fit and has to hold together more parts, so there is more excellent engineering and manufacturing to appreciate there. Replacement is very simple and everything just fits into place perfectly and securely thanks to the good quality of the product.
    One thing to note is that if you don’t work on your derailleur frequently, you should pay extra attention to the way derailleur and its hanger are placed before changing over, so you (unlike me) can put it back on correctly at the first go.

  18. Nord (verified owner)

    As advertised and more! The RAT system in the Cervelo R series has good design intention but negatives out weigh the positives. The good old bolt system is still the best for disc brakes. The Robert Axle solution is no fuss ultra reliable and light solution for this. It even removed the occassional brake rub! One the of best decision for my bike upgrade this year.

  19. Steve (verified owner)

    Exact fit on my Cervelo R3, 2018. A perfect solution.

  20. Paul (verified owner)

    Awesome in every way. EXACT fit replacement, simple instructions, high quality materials and fast delivery. Purchased front and rear axles.

  21. Patrick Naylor (verified owner)

    These are great. Bought a set to replace the standard Cervelo RAT axles, which wear out. These axles are much, much better. You will not regret buying them.

  22. Rich H (verified owner)

    Perfect for me, thanks!

  23. Bob Barnes (verified owner)

    RAT Extermination made easy! Nothing but positive things to say about this, including the Robert Axle Project product itself, the ease of installing, the performance of the new RAP axles, and the customer service and handling of my order. Great job, RAP! I purchased both front and rear axles to replace the R.A.T. axles on my Cervelo R5, and could not be more pleased with the result. The fit is perfect, including the required (and included) replacement derailleur hanger. The new axles are smoother, stiffer, quieter, lighter, and more aero than the R.A.T. axles with their large protruding levers. Yes, you must carry a 6mm hex key in order to remove the wheels, but I do that anyway, in a small multi-tool. Despite the good intention of the R.A.T. design as a quick-release axle system, the fussiness of its adjustment and the difficulty I found releasing the lever when sufficiently tight made it cumbersome and annoying in real use. The simple, light screw-in Robert Axles work perfectly, without frustration. I highly recommend this upgrade to anyone who has grown annoyed with the R.A.T. axles!

  24. Jean Claude Provencher

    Fits perfectly to my Cervelo R3, High Quality product

  25. Michael (verified owner)

    When trying to repair my Cervelo R5 I couldn’t get the replacement hanger from Cervelo or any on-line supplier so was very fortunate The Robert Axle Project was there. They quickly shipped a rear axle. It works perfectly and I like the cleaner look so much so I’m considering getting the front axle as well. Though I do like the speed a quick release front axle allows for ease of transport.

  26. Paul Domer (verified owner)

    High quality axle and great instruction manual. I appreciated that the instructions and pictures exactly matched my Cervelo. Everything fits perfectly.

  27. Jose Oliveira

    It did work perfectly to my Cervelo S3!! I should say gave to my bike a better looking. Thank you and great job.

  28. Martina (verified owner)

    I have a Cervelo S5 2022 and I don’t feel comfortable with RAT, so i was looking for something better. I find Robert Axle Project, I buy this product immediately!
    easy to setup, it was love at first Ride!

  29. Lisa Laws (verified owner)

    Did the job and probably lighter weight than the RAT from Cervelo. Customer service was fantastic. Thank you

  30. Doug (verified owner)

    It works perfect! Very easy to install. No more noise from the creaking RAT system. Makes my Cervelo the bike I expected. The Robert Axle is great solution.

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