We can be pretty sure that Shimano will launch a 13-speed groupset soon, and a listing on a German retailer website appears to confirm it.

This was first reported, as far as we know, by a Reddit user a few days ago and also picked up by Bikeradar yesterday.

The listing on Bike-Discount has now been removed, but it did list “Shimano 13-speed” as a freehub body option on new DT Swiss G 1800 Spline gravel wheels.

We’ve known for some time that Shimano is likely making the jump to 13-speed simply because it holds loads of patents where 13-speed cassettes are shown. That’s not proof in itself – patent applications are made for all sorts of products that never make it into the real world – but with Campagnolo already producing several 13-speed options and SRAM offering 13-speed wireless electronic groupsets tailored for gravel riding under its XPLR line, it would be strange if Shimano wasn’t working on it.

Shimano 13-speed patent comp

Shimano 13-speed patent comp (Image Credit: Farrelly Atkinson)

> New patent suggests Shimano 13-speed electronic groupsets are coming — here’s what we know so far 

The Bike-Discount listing isn’t far short of cast iron proof that 13-speed Shimano is on the way. When buying the new DT Swiss wheels, customers were asked to make a selection:

Freehub body (choose variant)

  • SRAM XDR (AXDR)
  • Shimano HG11s (ASF11)
  • Shimano MicroSpline 12s (ASL12R)
  • Shimano 13-speed (ASL13R)

It would be hard to think of an admin error that could have magicked up a standard that’s not going to exist. Naturally, Shimano is staying tight-lipped.

The exact form of Shimano 13-speed is harder to guess. The DT Swiss G 1800 Spline wheels are designed for gravel, so it’s not surprising that both Shimano HG (used for road applications) and Shimano Micro Spline (used for mountain biking) freehub options are available. Shimano’s GRX gravel groupset uses both HG and Micro Spline.

Why’s that relevant? Because we can’t really be sure if the ‘Shimano 13-speed’ freehub body option refers to road or gravel products – or both.

The product codes used on the Bike-Discount listing give us a clue. ASL12R is Shimano’s designation for the current Micro Spline freehub used by GRX 1×12. Following the same naming protocol, it’s likely that ASL13R is an evolution of ASL12R rather than an entirely new interface.

Dura-Ace, Shimano’s top-level road groupset is certainly due an update, the current version having been unveiled back in 2021. And Shimano’s new Dura-Ace wheels have the designation WH-R9370, whereas the current-generation Dura-Ace is R9250/R9270, suggesting that a new-generation groupset is in the offing.

> Shimano launches lighter, more aero Dura-Ace wheels

On the other hand, Shimano has launched a number of GRX 12-speed products over the past few years, while both SRAM and Campagnolo have offered 13-speed gravel components for some time. Shimano would doubtless like to follow suit sooner or later.

Beyond that, we’re just guessing. We’d say that Shimano is very likely to launch a new Dura-Ace groupset in the next few months, and that it’s likely to be 13-speed. Will it share a freehub standard with a new 13-speed GRX groupset? Or does this Bike-Discount leak refer only to a new GRX setup? We simply don’t know.

Plus, of course, it’s not just a case of adding an extra sprocket. There’s not a whole lot of spare space back there, which means alterations to the specs of other components.

Would you value 13 speeds for off-road riding, particularly if you run 1x? Would you want a 13-speed setup on the road, or is 12 (or fewer) plenty? Or are you playing the long game and waiting for 20-speed from one of the big brands?

If you have a theory about what’s going on, please let us know in the comments.