Madrone Cycles Eagle Derailleur Rebuild Kit Review: The Right to Repair

Photos by Logan Watts

Back in my professional bike-wrenching days, I remember bins full of broken derailleurs in various states of disarray. Some were bent and twisted beyond recognition, a catastrophic failure likely caused by something slamming them into the spokes, leading to sudden destruction and a long walk out of the woods. Others appeared mostly fine, with just a scratch or two, but had been relegated to the “broken” bin because they could no longer function properly. These were often stripped of their jockey wheels, cages, and other small parts for reuse on other derailleurs. Inevitably, I’d sort through these bins, selecting the best-looking parts to cobble together a derailleur that worked well enough. It was never perfect, but I found joy in revitalizing “broken” things, a subject Lucas explored in detail in his recent Ode to Maintenance.

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The parallelogram of the derailleur was always the crux of my operation, though. Pressed-in pins, tension-loaded springs, and tiny parts constantly kept me from fully disassembling them in my frugal repair attempts. If the parallelogram was bent—which happened frequently, though it was often hard to detect visually—the derailleur was effectively done. While cages, pulley wheels, and even clutches on Shimano derailleurs could be replaced with small parts, a bent parallelogram meant you’d need a whole new derailleur. Enter Madrone Cycles.

Madrone Cycles was founded in Ashland, Oregon, by Aaron Bland. The name is inspired by the native madrone tree (Arbutus menziesii), which grows along the western coast of the United States. This evergreen tree is known for its smooth, reddish-green bark that peels like paper, extremely hard wood, small pink and white flowers, and red fruit. Madrone Cycles notes that the tree “symbolizes their commitment to durability, uniqueness, and adaptability.”

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Aaron’s inspiration for founding Madrone came after a small crash involving his rear derailleur rendered it useless. Frustrated that such a seemingly minor incident cost him $600 to replace the AXS derailleur, he set out to develop a solution to help others avoid the same costly problem. Thus, the company’s mission to build a “rebuildable, sustainable, and high-performing” product was born.

What’s in the Box?

Madrone sent us their Missing Link Kit, Replacement Derailleur Cage, and Super Shims Kit. The packaging is simple yet effective, consisting of a cardboard box with small, labeled envelopes inside to keep everything organized, along with the impressive 3D-printed tools needed to get the job done. Madrone provides everything required to complete the job yourself, except for a 5/32 punch, which is needed to help remove and install the pins holding the parallelogram together. We didn’t have that size punch, but we did have an old 5/32 drill bit. While I don’t recommend using a drill bit (flipped upside down as a punch), it got the job done. Most local hardware stores carry one, and they shouldn’t cost more than a few dollars; it’s a handy tool to have around.

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The Missing Links Kit comes in three colors: Silver, Mustard, and Walnut. The kit includes links, bushings, snap rings, shims, fasteners, and all the necessary tools to install the kit. Madrone also offers a Replacement Derailleur Cage and pulley kit for $74. This kit features a replacement cage with Madrone’s unique design, which has a front profile that protrudes slightly further than a stock SRAM cage. This provides extra protection for the lower pulley from sticks and debris that could cause catastrophic damage. Both the cage and the solid pulleys are made from 6061-T6 aluminum, making for a durable and stiff upgrade.

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Rounding out the kit are the Super Shims. These shims are used to eliminate the slight wiggle in the mounting bolt that can develop over time as a derailleur ages. Madrone’s solution is to add a shim and a wavy washer to apply pressure on the bolt while allowing the derailleur to rotate around it. The kit also includes two O-rings to replace the stock SRAM ones.

The Rebuild

Installing the Madrone Missing Link Kit took about an hour the first time I tried it. The installation video is easy to follow and very comprehensive. They’ve done a great job of walking through each step in detail, offering tips and tricks to ensure everything goes smoothly. Having been a professional bike mechanic for years—and having worked at an off-road truck/fabrication shop before that—gave me some confidence going into it. Still, I’m not going to sugar coat it: with all its tiny parts and loaded springs, stripping down an AXS rear derailleur for the first time was a bit intimidating. That said, the overall process was pretty straightforward.

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It’s clear that Madrone put a lot of time and effort into the installation videos, and as a mechanic, I really appreciate that. Throughout the entire process, I kept thinking about how much work had gone into developing the replacement parts and tools. Madrone provides five 3D-printed tools that make the repair possible. The 3D-printed punch tool makes removing the pins and pressing them back in a breeze. Removing the torsion spring from a derailleur is somewhat easy, but getting it back under load is nearly impossible without the right tool. Madrone developed a Torsion Spring Clamp tool that makes reinstalling the spring far easier.

There’s also a bushing removal tool, which, while a bit awkward to use, gets the job done. They even provide a proper snap ring tool to remove those pesky snap rings from the pins. Having all the right tools and following the steps in the video gave me the confidence to get the job done.

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If taking apart an expensive derailleur isn’t your cup of tea, Madrone offers a rebuild service where you can ship them your derailleur, they rebuild it, and then send it back. Pricing for the rebuild service is available on their website. Overall, I really enjoyed the process of rebuilding both an AXS derailleur and a good old-fashioned cable-actuated one, and I’m glad to have done it myself.

Out on a ride

The XO1 Eagle derailleur I installed the Madrone kit on is my oldest derailleur. It came off my Why Cycles S7, which I bought from Why’s demo fleet in 2019 during a road trip to Colorado. Needless to say, it’s been through several bikes, countless miles, thousands of shifts, and a few crashes. The wear and tear were evident in the lackluster shifting I’d been experiencing for a while, but I was determined to keep it going as long as possible.

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I’m happy to report that after installing the full Madrone kit, the shifting felt like new again—maybe even a little better. The sloppy shifts I’d been dealing with were gone, replaced by smooth, crisp, and seamless transitions throughout the entire cassette. I think I even said to Logan, “Man, this shifts better than a new XO1 derailleur,” as I test-pedaled it around the yard just after the install.

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On the trail, the shifting remained just as consistent as it was in the stand and during my initial test ride. Better yet, after about 200 miles, I can confidently say nothing has changed. The only thing I’ve noticed is a slight increase in chain slap on the chainstay. I’m not 100% sure, but my initial thought is that the solid pulleys and larger cage of the Madrone replacement might be putting more leverage on the clutch mechanism, causing it to move more freely. It’s also possible that the clutch itself, which is now over six years old, is simply worn out.

Other than that minor issue, the derailleur has been flawless. I would recommend it to anyone looking to freshen up an old, worn-out derailleur or repair one that may have been damaged in a crash or tip-over. I can see this product being a game-changer in bike shops, where mechanics could potentially save customers a trip and some money by repairing rather than replacing their derailleur. Plus, it would keep one less item out of our ever-growing landfills.

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Madrone Derailleur Rebuild Kit Pricing

The pricing is where things get a little confusing, although Madrone recently updated their website to clarify it. Here are the breakdowns for the mechanical Eagle rebuild and the AXS derailleur rebuild:

Cable-actuated Eagle Derailleur Rebuild Kit

• Cable actuated Missing Links with tools: $119
• Cable actuated Missing Links (without tools): $89
• Cages (no pulleys): $55
• Pulleys: $55
• Pins for cable actuated derailleurs: $24
• Super Shims: $6

AXS Derailleur Rebuild Kit

• AXS Missing Links with tools: $129
• AXS Missing Links (without tools): $99
• Cages (no pulleys): $55
• Pulleys: $55
• AXS Pins: $29
• Super Shims: $6

It’s pretty easy to do the math and see that if you buy the entire mechanical rebuild kit, it’s more expensive than purchasing a cable-actuated GX derailleur, which you can get for $108, or an X01 for $170. However, in Madrone’s experience, around 9 out of 10 rebuilds only need Missing Links and Super Shims. Pins are rarely needed (Aaron estimates one out of every 20 rebuilds), and cages are only sometimes needed (usually, you can visually see a bent cage).

Madrone is actively working to frame these products as an a la carte menu, where you only pick what you need. Their “Which Parts to Replace” and “Deciding to Rebuild” pages explain more. Plus, if you value repairing things over throwing them away, the Madrone kit is worth it, especially considering it works almost better than new once installed. On the other hand, the $274/$244 (with/without tools) AXS rebuild kit is much cheaper than buying a new $350 GX or ~$500 AXS XO1 derailleur.

• Model Tested: Madrone AXS and Mechanical Rebuild Kits
• Place of Manufacture: Made in China, assembled in Oregon
• Manufacturer’s Details: Madrone Cycles