668% gear range! GRX 12s Di2 Mullet

Last few years I ran a GRX 11s Di2 setup with 46/36x 11-40 with an old XTR cassette and Wolftooth Road link. That worked beautifully so I tried to do something similar with the new 12s GRX Di2 2x. Shimano skipped the 11-40 ish range cassette for 12 so I had to try something else. Recipe: Switch to 46/31 rings from the standard 48/31 or 46/30. The smaller 15t step makes it possible for the RD to have enough take up.. just. Wolftooth Roadlink DM 10/45 Shimano cassette microspline freehub body Cut chain so its as short as it can be and still cross chain big-big with a bit of slack on the RD. Cross chain big-big is a tad noisy due mainly to the wider chainline of GRX. I wish there was a way to get 44/30 12s compatible chainrings with a standard road chainline. That would be perfect. With my tires, I have a 19.4" low, 130" high and 668% range. Insane gearing! Feb 2026 edit: For those that want a little less range and have an HG freehub, there are a few aftermarket 11-40, 11-42 and 11-46 12s cassettes on aliexpress. Most are cheap and heavy, but a viable option for some riders