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Shimano GRX RX820 Shifter/Brake Levers

What the checker says59will not fit

Run variant by variant through the gravel bike builder’s own engine. Every sentence below is the checker’s, unedited. Nothing here says this part fits your bike; it says what it does and does not fit among the parts we hold.

Checked against 841 verified gravel bike parts in this catalog. 779 produced no finding of any kind.

Will not fit

  • Will not fiterror · Rear DerailleurSpeed mismatch: Shifter 12s, Rear derailleur 13s. The drivetrain must share one speed count. On 5 of the 20 verified rear derailleurs in this catalog.
  • Will not fiterror · CassetteSpeed mismatch: Shifter 12s, Cassette 13s. The drivetrain must share one speed count. On 4 of the 18 verified cassettes in this catalog.
  • Will not fiterror · Front DerailleurDrivetrain mismatch: Shifter = shimano-grx-12, Front derailleur = sram-axs-road. Shifter, derailleurs and cassette must be one system. On 4 of the 11 verified front derailleurs in this catalog.
  • Will not fiterror · Rear DerailleurSpeed mismatch: Shifter 12s, Rear derailleur 11s. The drivetrain must share one speed count. On 4 of the 20 verified rear derailleurs in this catalog.
  • Will not fiterror · Rear DerailleurDrivetrain mismatch: Shifter = shimano-grx-12, Rear derailleur = shimano-grx-11. Shifter, derailleurs and cassette must be one system. On 4 of the 20 verified rear derailleurs in this catalog.

Rg 2x control, Crankset. 14 more findings from the same check, on up to 1 of the 32 verified cranksets each.

Rg actuation, Rear Derailleur. 9 more findings from the same check, on up to 2 of the 20 verified rear derailleurs each.

Rg drivetrain system, Cassette. 7 more findings from the same check, on up to 3 of the 18 verified cassettes each.

Rg actuation, Front Derailleur. 6 more findings from the same check, on up to 1 of the 11 verified front derailleurs each.

Rg chain std, Chain. 6 more findings from the same check, on up to 1 of the 17 verified chains each.

Rg drivetrain system, Rear Derailleur. 6 more findings from the same check, on up to 3 of the 20 verified rear derailleurs each.

Rg drivetrain system, Front Derailleur. 3 more findings from the same check, on up to 3 of the 11 verified front derailleurs each.

Rg drivetrain speeds, Cassette. 2 more findings from the same check, on up to 3 of the 18 verified cassettes each.

Rg drivetrain speeds, Rear Derailleur. 1 more finding from the same check, on up to 3 of the 20 verified rear derailleurs each.

Open a variant in the builder to see the ones that apply to your own parts.

The checker compares the dimensions listed in what we check, and what we don’t. “No conflicts found” means no conflict among those dimensions — not a guarantee that a build works. Errors mean it won’t fit; warnings mean it works but check; infos are notes.
Shimano GRX RX820
Photo: Shimano

$900.00 MSRP·620 g

What the maker states

System
Drivetrain system shimano-grx-12
Speeds
12-speed (rear index count the maker rates it for)
Actuation
Mechanical
Brake system
Disc-hydraulic
Side
Sold as a pair
Front shift
No front shifting
Source

Source: the maker’s page. Last checked 2026-07-17.

Checked against

The checker ran this model against every verified part below that it has a slot for, the same way it checks a build in the builder. What follows is the verdict it actually produced for that specific pairing — not a recommendation, and not a guarantee any of these parts fits your own bike.

6 of 488 counterparts with a page of their own that the checker actually probed this model against, in alphabetical order by brand and model — never by price, popularity or the verdict itself.

Where this sits

Previous: Shimano GRX ST-RX815Next: Shimano GRX ST-RX825All Shimano shifter/brake leversOpen a variant in the builder to see the ones that apply to your own parts