🚵♂️ SRAM Eagle AXS Transmission: the new revolution in mountain bike transmissions
SRAM has done it again. The American brand has once again revolutionized the mountain bike transmission market with the launch of the SRAM Eagle AXS Transmission, an innovative technology that completely redefines the concept of gear shifting.
More than just a simple groupset, this new proposal from SRAM represents a new generation of electronic transmissions that eliminates traditional components and simplifies the rider’s experience. A natural evolution after key milestones such as the legendary SRAM XX1 single chainring or the SRAM Eagle 12-speed, which transformed performance in the world of mountain biking.
🛠️ An unprecedented transmission system
The SRAM Eagle AXS Transmission introduces a radically different shifting system. Forget the classic derailleur hanger: this groupset mounts directly to the bike frame, which ensures perfect alignment and eliminates the need for manual adjustments.
In addition, tension screws and micro-adjustments are a thing of the past. This innovation not only improves shifting precision, but also reduces maintenance and potential failures during competition or technical rides.
The flat chain that comes with this groupset is thinner and stiffer, which also contributes to greater efficiency and stability in shifting, especially in demanding situations such as technical climbs or aggressive descents, which are common in mountain biking.
🚴♂️ And what about road bikes?
Although this groupset is specifically designed for mountain bikes, many of its innovations are generating interest among road cycling enthusiasts , especially for those seeking simplicity, reliability, and performance without complications. The direct integration into the frame and the elimination of elements prone to misalignment could also be the future for drivetrains on road bikes.
📈 SRAM continues to lead the way
With this launch, SRAM reaffirms its leadership in innovation within cycling. If it already revolutionized the market with the Eagle groupset, now it does it again with the Eagle AXS Transmission, designed for those who demand maximum performance on their mountain routes.
Are you ready to forget about adjustments and just focus on enjoying the trail?
Main innovations of the SRAM Eagle Transmission groupset
The main innovation of the SRAM Eagle Transmission groupset is that the rear derailleur is attached directly to the frame instead of to a derailleur hanger like the transmission systems we know so far. SRAM says this is the result of 8 years of R&D. Below we summarize in 10 points the highlights of this new groupset:
- There are 3 versions available: XX SL, XX, and X0. The first is lighter and faster, the second is more durable, and the third is the most affordable.
- The rear derailleur does not need screws to adjust tension or travel, so the shifting never goes out of adjustment. However, you must pay attention to the chain length.
- Spare parts are interchangeable if any part breaks, but keep in mind that this system is only compatible with bike frames that have a UDH mounting system.
- The new shift buttons, called Pod Controller, are smaller and lighter and can be mounted on the handlebar or on any brake lever, either right or left. It has two buttons that you can configure as you like.
- The cassettes have been redesigned to eliminate the jump between the penultimate and the last cog, which means gear changes will be smoother. The cassette of the SRAM XX SL version is the lightest SRAM has ever created, weighing only 345 grams. Yes, you read that right, a 12-speed 10-52 cassette under 350 grams. Incredible!
- The cranksets have also been redesigned in all available versions, and are lighter than the previous ones.
- The Eagle Transmission groups come with Quarq power meters that measure power in both legs for the XX SL version, and in the left crank for the XX and X0 versions.
- The chains are flat top type and are lighter thanks to a recess in all the links on the superior side. In this way, friction with the cassette and chainring is reduced and the entire drivetrain wears out less. They also have single-use PowerLock quick links.
- There are different prices for each version of this transmission system, but the cheapest one costs more than many mid-range bikes. The most expensive ones include the power meter.
- SRAM has also taken the opportunity to launch new brake levers designed to work with the T-Type Eagle Transmission system.
Let's now take a closer look at what really stands out about the SRAM Eagle Transmission group: 
The derailleur hanger is eliminated
This new Eagle Transmission shifting group is different from any other gear shifting system on the market. After years of development, it arrived to fulfill the dream of the perfect shifting system. And that's because this transmission does not use a derailleur hanger and has no adjustment screws. It literally can't go out of adjustment. The direct-mount derailleur is attached directly to the bike frame, creating a stronger, stiffer, and more stable connection. Thanks to this feature, the derailleur is always in the correct position relative to the cassette, allowing for more precise and faster shifting, even under heavy loads. It is important to note that these new direct-mount rear derailleurs will only be compatible with frames featuring the UDH system, which was another innovation SRAM launched a few years ago as part of its commitment to standardizing transmission mounting systems on all bike frames.
Greater durability thanks to the Flat Top chain
Durability is another feature that SRAM has sought to enhance with this new shifting group. Mountain bikes undergo enormous wear on drivetrain consumables due to the nature of the routes taken in this sport, exposing components to continuous friction from dirt, sand, mud, dust, flying stones, scratches from bushes and roots, etc. So what has SRAM done to reduce this wear in its Eagle Transmission group? Among other things, it has introduced a new chain that uses a technology called "Flat Top." Basically, it is a chain that eliminates the cut on the superior side of the links, similar to road group chains (although it is not compatible with them). With this design, the Eagle Transmission chain is thinner and more resistant without losing the strength needed to transmit power. The flat chain also prevents direct contact with the cassette teeth, thus reducing friction and therefore drivetrain wear. 
(Image: SRAM)[/caption]
New cassettes for more progressive ranges
The redesign of the cassettes and cranksets are also key features of the new SRAM Eagle Transmission system. The new cassettes offer a more progressive gear range, allowing for a smoother transition between cogs, while the new cranksets are lighter and designed to provide maximum efficiency in power transfer when pedaling. SRAM has eliminated the gap that existed between the second-to-last and last cog of the cassette. The 10-52 range is maintained but now includes 44 and 38-tooth cogs, which enhance that progressiveness. All group cassettes use XD drivers, and the XX SL version stands out as the lightest in SRAM's history, weighing only 345 grams.
New shift controller
The shifter is completely modular and replaceable, and setup is easier than in previous models. You only need a chain tool, an 8 mm Allen key, a Torx T25, and the specific torque setting. Another notable improvement is the shift controller; the levers are smaller and lighter and can be mounted on either the right or left side of the handlebar. Speaking of the electronic shifting version, one of the most interesting new features of this new Eagle AXS Transmission group is the customization available through the AXS app. Each AXS Pod Controller has two different buttons, and you can customize what each one does from the app. This way, you can control the RockShox Reverb AXS fork suspension with whichever button you choose, shift up with whichever button you want, and shift down with another. Additionally, you can choose Infinity or Bridge clamps so your controls are fully adjustable and set up exactly how you, and only you, want them. 
(Image: SRAM)
Fundamental questions about the new SRAM Eagle Transmission
So far, these are the innovations and technical novelties brought by the new SRAM shifting group. From here, we will try to answer the fundamental questions you are surely asking about the SRAM Eagle Transmission.
What exactly is the Eagle Transmission?
The SRAM Eagle Transmission is an advancement in mountain bike drivetrain technology. The most notable innovation of this group is the direct-mount derailleur, which installs directly onto the bike frame, without the need for a derailleur hanger. This means the adjustment is always perfect and does not require additional tuning.
What versions or Eagle Transmission groups are there and how do they differ?
There are three versions of SRAM Eagle Transmission groups:
- XX SL Eagle: the lightest and top-of-the-line, aimed at competitive cross-country.
- XX Eagle: a bit heavier than the XX SL, but designed for greater durability and resistance. It is intended for use on trails and enduro.
- X0 Eagle: more affordable and versatile, but also heavier than the other two.
What are the advantages of the SRAM Eagle Transmission group?
The SRAM Eagle Transmission offers a series of advantages compared to other shifting systems:
- Always precise shifting, even under heavy loads.
- It does not go out of adjustment, eliminates the need for a derailleur hanger and adjustment screws.
- Greater durability and resistance to wear.
- Greater compatibility with different bike frames and components.
- New customization and configuration options.
What are the disadvantages of the SRAM Eagle Transmission?
The main disadvantage of the SRAM Eagle Transmission groupset is its price. We are talking about a transmission system whose most affordable version has a starting price above 1,300 euros. Another disadvantage is that if you want to upgrade your bike by installing this groupset, you can only do so if the frame is compatible with the UDH direct mount rear derailleur system. Thirdly, the components of the SRAM Eagle Transmission group are not compatible with previous SRAM groups.
How much do the different versions of the SRAM Eagle Transmission group cost?
Below are the starting prices of the different SRAM Eagle Transmission groups in their standard versions and with power meter:
- SRAM X0 Eagle AXS E-Bike Transmission: €1,370 - €1,550
- SRAM X0 Eagle AXS Transmission: €1,900
- SRAM XX SL Eagle AXS Transmission: €2,650 - €3,250
- SRAM XX Eagle AXS E-Bike Transmission: €1,700 - €2,000
- SRAM XX Eagle AXS Transmission: €2,450 - €2,750
Conclusions
The innovative SRAM Eagle Transmission shifting group promises to mark a before and after in the world of mountain biking, offering a practical and efficient solution in terms of installation, maintenance, and adjustment of its shifting. In addition, it gets ahead of its main competitor, Shimano, in establishing the technological paradigm regarding derailleurs. The main problem is the price. It is not a groupset for everyone, and just the transmission components cost more than many bikes, but perhaps it is only a matter of time before the technological advances of this revolutionary shifting group reach the rest of the mid-range lines, as happened with other major SRAM technological revolutions such as single chainring transmissions and 12-speed cassettes.