Back to the future? With the new Eagle 90 Transmission drivetrain, SRAM are going all-in on simplification – bringing a shift cable to their direct-mount derailleur. So, no AXS battery, no hassle? But the big question is: can the cable-operated Eagle 90 Transmission drivetrain keep up with its electronic counterpart, or does it call for compromises?
Almost exactly two years ago, the web got inundated with pictures of SRAM employees jumping on derailleurs to prove their durability. That was when SRAM unveiled their new Eagle Transmission groupsets – all direct-mount, all electronic. Since then, the more affordable SRAM GX Eagle AXS Transmission was added to the line-up. Now SRAM are taking it a step further, introducing their most budget-friendly option yet: the cable-operated Eagle 90 Transmission. Despite forgoing electronics, it’s designed to deliver the same level of comfort and performance. The complete SRAM Eagle 90 mechanical Transmission kit retails at €730.
When SRAM introduced the Universal Derailleur Hanger (UDH) standard, few people realised what it would actually lead to – namely, a derailleur mounted directly to the frame, without a mech hanger. Since then, SRAM’s website has put the spotlight firmly on their Transmission models – aka T-Type drivetrains, which dominate the spec sheets of many bike manufacturers. There are hardly any modern MTBs left that don’t rely on the UDH standard. What remains are mostly lower-priced builds, which still rely on cable-operated drivetrains, which help save costs. And that’s exactly where SRAM are aiming their next move.
The new SRAM Eagle 90 Transmission in detail
At first glance, the new SRAM Eagle 90 Transmission looks sleek and clean, and it’s technically closely aligned with the proven T-Type ecosystem. Like the other Transmission models, it mounts directly to the rear dropout of the bike, making setup as simple as possible while delivering consistent shifting performance – especially under load. And since there’s no derailleur hanger involved, there’s one less thing that could bend or break.
In addition to the mounting method, the new mechanical Transmission drivetrain borrows technology from its electronic AXS counterpart – featuring specially designed shift ramps and cassette shaping to ensure smooth gear shifts. While the electronic AXS Transmission models use programmed shift delays, the mechanical version relies on rider intuition and the mechanical limits of the shifter itself. The trigger allows for a maximum of two shifts at once – or just one on an eMTB.
Another standout feature of the AXS Transmission derailleurs is their ability to move inward upon impact, and then automatically re-align themselves electronically. This isn’t possible with the mechanical version due to the cable-operated system. So if you have a hard “enemy contact” with a rock, there’s a chance that the Eagle 90 could get damaged. Thankfully, SRAM offer most components as individual spares at fair prices, allowing you to carry out repairs at home.
The SRAM Eagle 90 Transmission components at a glance
The Eagle 90 rear derailleur weighs 387 g and stands out for its modular design: components like the parallelogram, damper unit, cage, pulleys, cable, and housing are all available separately and can be easily replaced. This improves long-term durability for the €205 derailleur. It features aluminium skid plates on the outside to prevent it from snagging on the ground and comes with a clean, well-finished look in silver and black.
On the handlebar-end, there’s no need for an AXS pod – instead, the Eagle 90 relies on a mechanical trigger shifter. It’s available in a 2-click version for mountain bikes and as a 1-click version for eMTBs. Like SRAM’s latest brake levers, the new trigger features Stealth cable routing, aligning perfectly with SRAM brake-lineup to ensure a clean cockpit even with a cable-operated drivetrain. Important: The Eagle 90 rear derailleur isn’t compatible with older SRAM triggers due to a different cable-pull ratio. To match the clean cockpit, SRAM also offer a dedicated dropper post lever, which is designed to match both the look and routing of the new trigger system. Even with four cables on the bars, a sleek setup is possible. The dropper lever costs €45, while the trigger shifter retails at €55.
The aluminium cranks of the Eagle 90 bear a strong visual resemblance to those of the GX Eagle Transmission but use a more fragile-looking steel chainring. In the tested 165 mm version with two bashguards, the DUB crankset weighs in at 802 g – around 50 g more than the comparable GX setup. The cranks are available in lengths from 175 mm down to 155 mm, and for e-bikes, from 170 mm to 150 mm, with 5 mm increments.
The XS-1275 cassette is from SRAM’s existing T-Type range and the same found on the GX Transmission. Like all T-Type cassettes, it features 44 precisely defined shift ramps for smooth and accurate gear changes, and it offers the familiar 520% gear range. The cassette tips the scales at 440 g and costs €300.
Like the rest of the T-Type eco-system, the Eagle 90 Transmission chain relies on SRAM’s signature Flat Top design. The flattened outer plates can only be installed in one direction and will be familiar to many from the road cycling world. The Eagle 90 Transmission chain is the same one used for the SRAM GX Eagle AXS Transmission drivetrain and comes in at 285 g, retailing at €60.
The full SRAM Eagle 90 Transmission kit includes cranks, cassette, derailleur, chain, shift cable, housing, and trigger – everything you need to convert your bike. The total weight of the set is 2,132 g, which makes it roughly 100 g heavier than the wireless GX AXS Transmission. In return, you’ll get a more affordable, fully mechanical alternative. Opting for the Eagle 90 starter kit means a complete drivetrain upgrade for €730. If you’re upgrading an eMTB, you can save a little more – the e-bike-specific set is available from €720, depending on motor compatibility.
However, since all T-Type components are cross-compatible, you don’t necessarily need the full Eagle 90 kit. If you’re switching from a wireless SRAM Transmission drivetrain and want to ditch the battery and wireless tech, you can simply install the derailleur, trigger, and cable housing – nice. The same goes if you’re starting out with a mechanical setup and plan to upgrade to an electronic one.
Nearly all parts of the SRAM Eagle 90 Transmission are replaceable, which makes it especially repair-friendly, and also opens the door to mixing and matching with higher-end components – like swapping in a carbon cage to shave off some weight.
| Component | Weight | Price |
|---|---|---|
| SRAM Eagle 90 Transmission Derailleur | 387 g | € 205 |
| Crankset Eagle 90 (DUB, 32 T) | 802 g | € 170 |
| Trigger Eagle 90 shifter (2-Click) | 129 g | € 55 |
| Cassette Eagle 90 XS-1275 | 440 g | € 300 |
| Chain Eagle 90 126 Glieder | 285 g | € 60 |
| SRAM Eagle 90 Mechanical Transmission Set | 2.132 g | € 730 |
Variants, pricing and availability of the new cable-operated SRAM Eagle 90 Transmission drivetrain
The new SRAM Eagle 90 Transmission isn’t launching alone. Alongside it, SRAM are also introducing the Eagle 70 Transmission, which is intended primarily as an OEM component. However, it will still be available to private customers – just not as a complete kit like the Eagle 90.
The Eagle 70 derailleur is priced at €135 but is less modular than the Eagle 90 version. The parallelogram is riveted rather than bolted, meaning that you can replace only the cage – no other parts are available as spare. The matching trigger costs €35 and comes with a fixed clamp, offering less adjustment options and no Matchmaker compatibility.
Both mechanical Transmission drivetrains, the SRAM Eagle 90 and Eagle 70, are set to be available from March 2025 – and we’ve listed all the individual components along with their weights and prices for you below.
| Component | Weight | Price |
|---|---|---|
| SRAM Eagle 70 Transmission Derailleur | 415 g | € 135 |
| Crankset Eagle 70 (DUB, 32 T) | 895 g | € 100 |
| Trigger Eagle 70 shifter (2-Click) | 145 g | € 35 |
| Cassette XS-1270 | 565 g | € 240 |
| Chain Eagle 70 126 Glieder | 270 g | € 35 |
Installation & setup of the mechanical SRAM Eagle 90 Transmission
The good news first: mounting and setting up the Eagle 90 T-Type is fairly straightforward for a mechanical drivetrain, since the Transmission system has no limit screws, nor a B-screw. The only fiddly part is routing the shift cable through the frame – assuming there isn’t one already in yours. If you’ve previously installed a Transmission derailleur, the process is pretty similar. There’s a full guide to T-Type installation available separately, but here’s a quick overview of the key steps and differences:
- If present, remove the SRAM UDH derailleur hanger first. Loosely attach the derailleur to the frame – do not fully tighten it yet. Leave the thru-axle one turn loose as well.
- Shorten the chain to the exact length – no guesswork! The SRAM app will help you find the right length easily.
- Shift into the setup gear – but how, without cable tension? There’s no familiar silver setup pin like on the AXS versions. Instead, there’s a hole for a 4 mm Allen key. And yes, a 5 mm fits too, but that’s only relevant for specific bikes, e.g. with high-pivot suspension. So: push the derailleur inward by hand until you can insert the 4 mm Allen key – then release.
- The derailleur will now stay in the setup gear and must be gently pulled back to tension the chain.
- Tighten the derailleur to 35 Nm. Tighten the thru-axle according to manufacturer specs.
- Remove the 4 mm Allen key, pull the shift cable tight in the hardest gear, and fine-tune the cable tension – ideally during a quick test ride.
- Time to ride!
If you’ve previously battled with traditional drivetrains – upper and lower limit screws, B-screw, and chain wrap – you can breathe easy with the mechanical Transmission: once the initial setup is done correctly according to the guide, cable tension is the only variable left to adjust.
The SRAM Eagle 90 Transmission on Test – How recisely and Reliably Does it Shift?
After a quick and straightforward installation, it’s straight out for the first test ride. The trigger feels great under the thumb, with comfortable ergonomics and crisp, satisfying haptic feedback – just as you’d expect from SRAM’s mechanical shifters. Initially, you’ll need to make a few fine adjustments to the cable tension to get everything running smoothly. Once the housing settles and you’ve shifted through all the gears a few times, the system runs smoothly. With minimal thumb pressure, the gears shift cleanly and precisely under load – provided the system has been fine-tuned correctly.
Gear changes are impressively smooth – even under heavy pedal pressure. No crunching, no metallic clunks – just crisp, clean shifts. In terms of shifting performance, there’s no noticeable disadvantage over the electronic version. The two-click trigger is intentionally designed to slow down shifting slightly in favour of overall performance. And in most cases, two easier gears are more than enough for sudden kickers on unfamiliar trails. As usual, upshifts are limited to one gear per click.
For eMTBs, SRAM consistently recommend the single-shift trigger. Why? It mimics the slight pause the electronic AXS Transmission takes during multi-shifts to avoid cross-chaining and excessive stress on the drivetrain. And it works surprisingly well in mechanical form too. Even under full motor power, the gear changes remain smooth and trouble-free.
If you experience light rattling during long climbs, it’s likely time for a minor cable tension tweak. Over time, cable friction or housing wear can creep in and may require maintenance, lubrication, or a full replacement of the cable (and maybe housing). During our test, there had no issues with chain slap or weird noises coming from the drivetrain – just a solid, reliable mechanical shifting solution that never needs charging and won’t leave you stranded because of a dead battery.
Conclusions about the new SRAM Eagle 90 Transmission drivetrain
With the Eagle 90 Transmission drivetrain, SRAM completemented their drivetrain line-up – and it’s anything but a step backwards. For those who prefer to ride without worrying about dead batteries or having too much tech on their mountain bike, the Eagle 90 now offer full access to the Transmission experience. Despite using a cable, it still benefits from easy setup, straightforward adjustment, and a wide range of spare parts. Shifting performance is barely distinguishable from the electronic version. Even under load and with high chain tension, the chain remains securely in place.
Tops
- Easy installation and setup
- Clean, reliable shifts even under load
- Low system complexity
Flops
- Needs occasional fine-tuning
- Potentially more maintenance over time
More info via sram.com
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Words: Julian Schwede Photos: Peter Walker
