Long before UDH became a well-known acronym and widely-adopted standard, our first Patent Patrol sneak peek at SRAM’s direct mount T-type derailleurs illustrated a clearly mechanical Transmission. Now six years later, patent offices just published an updated SRAM mechanical T-type application. And at the same time, bike dealer sites have been trickling out leaked specs for not one, but two different SRAM mechanical Transmissions.
It looks like we’re on the verge of seeing 2 all-new more affordable mechanical shift SRAM Transmissions. Are mechanical SRAM NX Eagle Transmission and SRAM SX Eagle Transmissions coming very soon?
SRAM Mechanical T-Type Transmission derailleurs very soon!
The secret of the new SRAM Mechanical T-Type Transmission broke first with references to a “SRAM Eagle 70 Transmission”. But how did we get here?
Sure, we saw a direct-mount mechanical SRM derailleur all the way back in 2018 with that first patent filing. But then, there was no more concrete mention of mechanical shifting for six years, while SRAM pushed their UDH standard out onto tons of off-road bikes and used the T-type mount as a sales driver for their top wireless AXS electronic drivetrains – first for XX SL, XX & X01, then more attainable GX AXS before going gravel with Red XPLR AXS. And, most affordably but still electronic for OEM-only as S1000 AXS, just last summer.
So what is Eagle 70 Transmission?
We read rumors of ’70 Transmission’ as early as September last year, but didn’t really have much confirmation as to what that meant. And I hadn’t seen it written in any publicly accessible space until this past month. Digging deeper into upcoming bike specs online though, I uncovered a second – seemingly compatible – reference to “Sram Eagle 90 Transmission”.
That’s when it really started to click.
Both 70- & 90-level specs include a reference to a “Single-Click” shifter. And there’s importantly no cross reference to any AXS (wireless), all but confirming that this is mechanical shifting, not electronic. Some of the mixed-level specs refer to an NX derailleur – traditionally just below GX in the SRAM hierarchy. And some say just Eagle 70, which could be the OEM-only SX level?
Interestingly, it does seem that 70 Transmission is backward compatible with the current AXS Transmission. And some of you may already have the new – probably lower-priced – components on your (e)bikes. Specifically, it looks like some MY25 Bulls eMTBs with SRAM GX AXS electronic drivetrains may have already been spec’d with the new ‘Eagle 70 Transmission’ cassettes, likely as a cost savings tool.
What’s new in this latest SRAM Mechanical Transmission patent?
The language of patent applications is always quite dense, and often hard to parse. But one key difference since we first saw a mechanical derailleur in SRAM’s direct mount T-type Transmission filings, is that this new US20240246634A1 application (and to be fair, a few others since) is now actually for the derailleur, not the direct mounting interface, like several previous filings we have covered. The illustrations though, are just like we’d seen before.
That said, a few other previous patents also directly addressed this “Rear gearshift mechanism for coaxial installation” solution. What’s new since those as far as I can tell, is SRAM is now defining more clearly how the new direct-mount derailleur butts up directly against the rear wheel’s axle endcap, and better guides it into place. This could be an update for easier wheel installation. Or it could possibly remedy the issue where current T-type derailleurs can be poorly aligned or misaligned in the frame because of the crash-proofing slip design that allows them to rotate out of the way of an impact. But since there is no conventional B-tension screw, it is not always easy to be 100% sure that the derailleur is correctly realigned after such an impact.
Interestingly, even though the T-type direct-mount should ensure ‘perfect’ cassette alignment like with AXS Transmission, it looks like these new SRAM Mechanical Transmission derailleurs will get hi/low adjust screws again, based on all of the patent drawings.
I suspect we’ll have to wait for the final SRAM Mechanical Transmission launch to get into those details.
When is it coming?
I’m not going to out any bike brands here, because that doesn’t add anything to this still-developing story…
But what I can say is, there is at least one big bike brand out there with product page right now promising a new spec of a current model with “New SRAM Eagle Transmission” set to be available from March 27, 2025.
And how much will it cost?
That new spec also happens to sell for a full 2000€ less than the same model spec’d with a SRAM GX AXS Transmission (more premium suspension spec, but also still alloy wheels).
A SRAM GX AXS upgrade kit only costs you about 600-650€, so obviously you aren’t going to save two grand with a mechanical SRAM Transmission. But what it probably means is that you’ll start to see Transmission-equipped bikes and ebikes selling around the same pricing level as you would see with current mechanical GX Eagle or even cheaper than Shimano XT.
