[Updated – again] SRAM update means T-Type is now faster, but is it fast enough?

After years of riders noting that T-Type derailleurs slow down significantly after 3-4 shifts, SRAM is finally providing a fix. The brand released Firmware 2.53.8, a free update available now through the AXS app, that improves Eagle AXS Transmission cassette mapping.

We’ve installed the update and tested it out on the trails. Read on to see if it makes the difference SRAM needs to stay on top of the wireless game.

Cassette mapping: speed vs reliability

SRAM’s T-Type is designed to provide reliable and smooth wireless shifting under load. The initial release prioritized the speed at which SRAM thought it could best deliver shifting under load and, the brand says, long-term durability. The new update comes after further testing that it says shows it could preserve both those features and still offer faster shifting.

Cassette mapping refers to the combination of the brands “X-Sync technology” on the cassette and the sequence of derailleur movements controlled by the AXS firmware. The timing of the derailleur’s movement, SRAM says, uses a “shift sequence” with “specific timings that let the chain move across the cassette while maintaining full engagement.” That is, the chain must fully engage with one cog before AXS will let it start moving across to the next cog. In contrast, Shimano’s HG+ is designed to allow the chain to engage while also continuing to move the chain across the cassette.

Firmware update 2.53.8

The update means, SRAM says, ” that on successive shifts of three or more, the derailleur will move quicker between gear positions.”

That is, the brand quickly clarifies, not the same as saying that Eagle Transmission will shift quicker.

“It can speed up successive shifts of three or more, but this is largely dependent on the cassette. Shifting between cogs is enabled by the rotational speed of the cassette in combination with the derailleur movement between gear positions. These are two independent movements, whereby the derailleur position must move first before the chain can be released to the shift lanes of the cassette to change between cogs. Firmware 2.53.8 is designed to align better with common cassette rotational speeds while you ride.”

Clear as day, right?

The update is, as mentioned, available freely on the SRAM AXS app now.

How fast is faster?

Updating the shifter and derailleur is pretty straight forward and quick. It takes a few minutes to do both and you’re on your way.

How much faster does it make T-Type? On our XO derailleur, it cut about two seconds off the time it took to go all the way across the cassette and back. From about 12 to about 10 seconds for a complete there-and-back run. There is still a noticeable restriction on the speed SRAM allows the derailleur to move after 3 or 4 shifts, but it’s definitely less extreme than before.

This brings SRAM closer to the speeds of Shimano’s new Di2 groups. Closer, but still not particularly close. Running up and down an XT group was, by comparison, under 7 seconds. So SRAM is faster than it was, and having that free update be so readily available is appreciated. But SRAM is still erring on the side of reliability, and “full engagement” when shifting under power over speed.

Faster feels even faster on the trails

Shifting time on the stand is one thing, but the real test is how this update feels on the trails. The slight improvement SRAM gest in moving to easier gets makes a bigger difference than I’d expected. A personal annoyance with SRAM’s self-limited speed on T-Type is how slowly it moved when I was hunting for easier gears, quickly. It’s one thing to say the derailleur will keep shifting under load, but that only works if you can keep the cranks moving. The update makes it much easier to dump gears when transitioning quickly from a fast downhill to a steep, slow uphill.

Grabbing more gears still happens at a more steady pace, to be clear. And that still can be annoying, but not as annoying as stalling out on a steep section while you wait for your derailleur to catch up with the trail.

Two additional notes. This update will be installed automatically on all new T-Type groups going forward. So if you buy a new bike with T-Type, any level of T-Type, this update will already be installed. Second, this faster multishift mode is still not available for e-bikes of any kind. SRAM is still very clear that using multishift with a motor voids any warranty.