The unveiling of SRAM's Transmission drivetrains has been one of the most noteworthy announcements of the last few years. Today, the drivetrain giant has brought what was reserved for AXS or wireless shifting to a pair of mechanical or cable-actuated drivetrains. Meet Eagle 90 and Eagle 70.

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With T-Type AXS, SRAM believes that it has delivered the perfect mountain bike drivetrain, and now, thanks to the usual trickle-down effect seen throughout the cycling industry, the brand has brought the Full Mount, hangerless interface to a cheaper cabled alternative.

Full Mount, as seen on the T-Type AXS drivetrains, eliminates the need for a derailleur hanger as it mounts directly to the frame via its UDH or Universal Derailleur Hanger mount. The result is a stiffer and stronger join between the mech and frame, for a more resilient mech and solid shifting even when under power. And, of course, if there's no hanger to bend, there are fewer opportunities for failure.

2025 sram eagle 90 N hero 2.jpg, by Liam Mercer

T-Type brought a new setup procedure to drivetrains and on Eagle 90 and 70, there are no b-tension or limit screws and it follows a very similar setup method. Using SRAM's app, or guide the user can find their chain length, then hang the derailleur. However, there are a couple of extra steps before adjusting cable tension or introducing a cable to the mech, b-tension is set by pushing the derailleur and chain into the setup cog and locking it in place using a 4mm Allen key. Once the b-tension is dialled, only then can cable tension be sorted.

Of course, with new mechanical drivetrains come new mechanical shifters and these are all-new units. This time around, they follow SRAM's Stealth architecture as found on the brand's brake range. As such, the shifters sit closer to the bar, allowing for a cleaner look and tidier cable routing. There are two shifters on offer: one with a dual-click downshift and another with a single-click downshift directed towards e-mountain bike use.

2025 sram eagle 90 N shifter.jpg, by Liam Mercer

SRAM claims the Eagle 90 derailleur is the most rebuildable the brand has ever created and that's backed up with a full suite of replacement components. According to SRAM, the mech only requires two tools for full disassembly. Like its pricier AXS range mates, replaceable skid plates are present.

The Eagle 90 crank is forged from aluminum and comes in lengths from 175mm to 160mm. If you're an e-MTBer, you can go as short as 150mm. That crankset is home to a stamped steel chainring, which has been chosen for its durability and there's a pair of removable and independent bash guards – these are specific to the size of the chainring. Both drivetrains also feature a 55mm chainline.

2025 sram eagle 70 N stand.jpg, by Liam Mercer

Eagle 90 borrows the same cassette and chain as GX T-Type AXS but here are a few changes on the OEM-only Eagle 70. Namely, the three-bolt chainring interface on the crank and the XS-1270 cassette that works with a traditional splined freehub body. That said, the cassette still features the 10-52T range. Eagle 70 also comes with its own chain.

If you're looking to upgrade to a Transmission drivetrain without spending AXS money, Eagle 90 will set you back £655, while e-MTB drivetrains are priced at £645.

For some first impressions on SRAM's new Eagle 90 Transmission kit, check out the Eagle 90 first ride review.

• www.sram.com

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