
by Stan Purdum
If you’ve been cycling for a long time, you probably have some sense of the various component groupsets Shimano offers for road bikes. (If not, see the road bike groupset hierarchy here.) But as gravel riding has gained popularity, component manufacturers have introduced a new and separate specific hierarchy of groupsets to meet the needs of gravel riders.
Shimano labels their gravel groupsets as GRX to clearly distinguish them from their road and mountain bike sets. The company makes a point of saying that their GRX sets aren’t “a reworked set of road components,” but rather are “a ground up look at how cyclists want to explore their world.”
Specifically, the GRX sets offer wider gear ranges than equivalent road bike groupsets and are designed to handle the increased braking demands of gravel riding. The rear derailleurs can handle much larger cassettes and feature gravel-tuned clutch tension to reduce chain-slap and prevent the chain from being dislodged over bumpy surfaces. And, compared with existing road components, the chainline of each GRX set has been bumped outward by 2.5mm for increased tire and frame clearance. (This means that the GRX double cranks and GRX front derailleur must be paired together.) A lever on the derailleur allows you to disengage the clutch to make removing the rear wheel easier.
A couple of things aren’t redesigned. The cassettes and chains Shimano already produces for their road and mountain bike links are compatible with the GRX sets.
Below is a quick look at the three tiers of groupsets Shimano makes for gravel bikes. The bulleted list for each tier shows the components specifically offered for that level. However, Shimano says that some components from each of the three tiers can be mixed and matched to form an appropriate set up for each rider. These charts show how these components can be mixed and matched.

GRX Di2 11-Speed
https://bike.shimano.com/en-EU/product/component/grx-di2.html
Di2 stands for “Digital Integrated Intelligence” — Shimano’s version of electronic shifting — which provides instant, accurate, lightning-fast shifts every time.
Differing combinations of cranksets and cassettes enable this groupset to be built to match how you ride. The 11-28T cassette is borrowed from Shimano’s Ultegra road series, and the 11-34T also comes over from their road groupsets, but the 11-40 is from Shimano’s Deore XT mountain bike series. The double crank 48/31T has a 17-tooth jump between the two rings, which is the largest Shimano has ever produced.
New bikes that come with the GRX Di2 11-Speed groupset installed cost about $3,300 and up.
- Shifting: Electronic, semi-wireless
- Speeds: 1 x11, 2 x 11
- Chainrings: 42T, 40T, 48/31T
- Cassettes: 11-28T, 11-34T, 11-40T
- Brakes: hydraulic disc

GRX 11-Speed
https://bike.shimano.com/en-EU/product/component/grx-11-speed.html
This is the mechanical-shift version of the Shimano’s 11-speed groupset and is available with an 11-46T cassette, making an even wider range of gears possible.
New bikes that come with the GRX 11-Speed groupset installed cost about $2,500 and up.
- Shifting: Mechanical
- Speeds: 1 x11, 2 x 11
- Chainrings: 42T, 40T, 48/31T, 46/30T
- Cassettes: 11-28T, 11-34T, 11-40T, 11-46T
- Brakes: hydraulic disc

GRX 10-Speed
https://bike.shimano.com/en-EU/product/component/grx-10-speed.html
This is a less expensive option, but a solid performer on the gravel.
New bikes that come with the GRX 10-Speed groupset installed cost about $2,000 and up.
- Shifting: Mechanical
- Speeds: 2 x 10
- Chainrings: 46/30T
- Cassettes: 11-28T, 11-36T
- Brakes: hydraulic disc
Stan Purdum has ridden several long-distance bike trips, including an across-America ride recounted in his book Roll Around Heaven All Day, and a trek on U.S. 62, from Niagara Falls, New York, to El Paso, Texas, the subject of his book Playing in Traffic. Stan, a freelance writer and editor, lives in Ohio. See more at www.StanPurdum.com.
Are there any cassette limits for 2×11 grx. My gravel bike came with 11-34T cassette and I would like to move to 11-40T. Also, what happened to Shimano 11-36T 11 speed cassettes, I own two (on road bikes) but they seem to have disappeared?
I think the max cog for the 2×11 is 40T, but please identify your RD first then look it up. I have the GRX RD-RX810 and the total capacity is 40T. Though its meant for a 11spd RD, I’ve installed it to a 2×10 as 11-40T.
I can not find information for the combination of Shimano`s 48/31 with cassette 11-40T or bigger 1-42. I would appreciate if someone can explain tome is it possible?
11-42T. Sorry.