SRAM’s new S-1000 Eagle Transmission-spec electronic, wireless drivetrain is the newest addition to the hanger-free components launched in 2023 – but you can't buy them as a cheaper Transmission upgrade for your bike.
While the aim of S-1000 is to reduce the cost of Transmission-family components, this newest mountain bike groupset will, for the time being at least, only be available as original equipment (OE).
That means it’ll be fitted to some complete bikes, but you won’t be able to pop down to your local shop and buy any specific S-1000 components or a full groupset to fit to your current bike.
This is also the first time that SRAM is offering roughly the equivalent to NX-level components with wireless AXS technology, previously reserved for the GX tier or higher. SRAM's drivetrain tiers cover (from most expensive to least expensive) XX1, XX01, GX, NX and SX, and Transmission tiers now cover XX SL, XX, X0 and S-1000.
Trickledown technology of this nature is great for the consumer. Hopefully, it means we’ll see brands speccing electronic shifting on more affordable bikes.
SRAM S-1000 Eagle Transmission Derailleur
For those who have seen GX Transmission, the S-1000 derailleur’s looks will be familiar, thanks largely to the horizontally-mounted battery.
It also shares the same direct-mount design – that eschews the derailleur hanger in favour of mounting it directly to the frame’s dropout – and adjustment-free installation, just like all other Transmission components.
Also identical is the software-based ‘cassette mapping’, where the derailleur waits for a cassette ramp before shifting gear.
Differentiating it from GX is the S-1000 derailleur's “unique black anodized finish” and a clutch system that now uses a “drag spring damper.”
However, the S-1000 derailleur can still be fitted with a clutch or cage from any other Transmission level, whether that’s XX SL, XX, X0 or GX, according to SRAM.
The higher-spec derailleurs' rebuildable parts are also carried over.
Both the outer skid plates and two-piece outer link can be swapped using common tools, and like the other derailleurs, the cage is removed by rotating it.
The derailleur is compatible with all of SRAM’s AXS controllers and the AXS smartphone app.
SRAM S-1000 Eagle Transmission cranks
Built from forged aluminium, the S-1000 cranks are claimed to be robust and reliable.
They’re available in 155mm through to 175mm lengths, in 5mm increments, and work with any Transmission eight-bolt chainring.
That means they’re compatible with the same composite bash guards found on GX and X0-level rings. Bash guards can be retrospectively fitted to the S-1000 crankset, but standard fitment is determined by the bike manufacturer.
An eMTB-specific crankset is also available, and is compatible with SRAM, Brose, Bosch and ISIS bottom bracket ebike motors.
SRAM XS-1270 Eagle Transmission cassette
The new S-1000 Eagle Transmission cassette has the same 10-52t range as all of SRAM’s XD Driver Eagle cassettes.
The same X-Sync design as the rest of SRAM’s Transmission cassettes is also said to deliver improved shifting performance under load.
Again, it's compatible with all other Transmission components, including derailleurs and chains.
The cassette, which uses the Shimano HyperGlide (HG) freehub body standard, has space for the 10t sprocket by integrating it with the lockring in one piece.
SRAM said it’s working on aftermarket availability for the full cassette.
Currently, only the 10-18t sprockets will be available to buy as replacement parts. The 10, 12, 14 and 16t gears are a welded cluster, while the 18t is a separate cog.
No chains for S-1000
Chains are ostensibly missing from the S-1000 lineup.
Only SRAM’s flattop MTB chains are compatible with Transmission-style drivetrains but there's no S-1000-specific model, so bike brands will have to spec GX or higher chains on their S-1000-equipped bikes.
DB8 brakes get Stealth refresh
Also launched are updated DB8 brakes, which prior to the new Maven brakes were SRAM’s first foray into mineral oil stoppers.
While the DB8 caliper, brake pads, bleed kit and rotor compatibility remain unchanged, the Stealth update moves its reservoir and cable closer to the bar, akin to the rest of the SRAM’s Stealth brakes.
Retailing for £132 / $137 / €148 an end, according to SRAM, they’re a relatively affordable means to access Code-like power.
