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Shimano GRX Shifter/Brake Levers

What the checker says141will not fit

Run variant by variant through the road 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 1035 verified road bike parts in this catalog. 928 produced no finding of any kind; that is GRX ST-RX820 Shift/Brake Lever (pair, 2x). GRX ST-RX820-LA Shift/Brake Lever (pair, 1x) clears 882. Each variant produces 71 to 117 distinct errors and 0 distinct warnings.

Will not fit

  • Will not fiterror · CassetteDrivetrain mismatch: Shifter = shimano-grx-12, Cassette = sram-axs-road. Shifter, derailleurs and cassette must be one system. On 10 of the 34 verified cassettes in this catalog. Applies to all 2 variants.
  • Will not fiterror · CassetteDrivetrain mismatch: Shifter = shimano-grx-12, Cassette = shimano-road-12. Shifter, derailleurs and cassette must be one system. On 7 of the 34 verified cassettes in this catalog. Applies to all 2 variants.
  • Will not fiterror · Front WheelBrake system mismatch: Levers = disc, Front wheel = rim. Disc and rim-brake parts do not mix on one build. On 7 of the 101 verified front wheels in this catalog. Applies to all 2 variants.
  • Will not fiterror · Rear WheelBrake system mismatch: Levers = disc, Rear wheel = rim. Disc and rim-brake parts do not mix on one build. On 7 of the 112 verified rear wheels in this catalog. Applies to all 2 variants.
  • Will not fiterror · Front CaliperBrake system mismatch: Levers = disc, Front brake = rim. Disc and rim-brake parts do not mix on one build. On 6 of the 35 verified calipers in this catalog. Applies to all 2 variants.
  • Will not fiterror · Front DerailleurDrivetrain mismatch: Shifter = shimano-grx-12, Front derailleur = shimano-road-12. Shifter, derailleurs and cassette must be one system. On 6 of the 22 verified front derailleurs in this catalog. Applies to all 2 variants.
  • Will not fiterror · Rear CaliperBrake system mismatch: Levers = disc, Rear brake = rim. Disc and rim-brake parts do not mix on one build. On 6 of the 35 verified calipers in this catalog. Applies to all 2 variants.
  • Will not fiterror · Rear DerailleurSpeed mismatch: Shifter 12s, Rear derailleur 11s. The drivetrain must share one speed count. On 6 of the 29 verified rear derailleurs in this catalog. Applies to all 2 variants.

Rg 2x control, Crankset. 46 more findings from the same check, on up to 1 of the 54 verified cranksets each.

Rg actuation, Rear Derailleur. 30 more findings from the same check, on up to 1 of the 29 verified rear derailleurs each.

Rg actuation, Front Derailleur. 18 more findings from the same check, on up to 1 of the 22 verified front derailleurs each.

Rg drivetrain system, Rear Derailleur. 9 more findings from the same check, on up to 4 of the 29 verified rear derailleurs each.

Rg chain std, Chain. 8 more findings from the same check, on up to 1 of the 25 verified chains each.

Rg drivetrain system, Cassette. 7 more findings from the same check, on up to 5 of the 34 verified cassettes each.

Rg drivetrain system, Front Derailleur. 6 more findings from the same check, on up to 5 of the 22 verified front derailleurs each.

Rg drivetrain speeds, Cassette. 5 more findings from the same check, on up to 5 of the 34 verified cassettes each.

Rg drivetrain speeds, Rear Derailleur. 4 more findings from the same check, on up to 3 of the 29 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 ST-RX820 Shift/Brake Lever (pair, 2x)
Photo: Shimano

$360.00 to $380.00 MSRP·552 to 780 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 (on 1 of 2 variants); Shifts a front derailleur (on 1 of 2 variants)

A value shown as a set or a range differs between this model’s variants and is never one variant’s spec.

2 verified variants

VariantFront shiftPrice (MSRP)WeightSourceLast checkedBuild
GRX ST-RX820 Shift/Brake Lever (pair, 2x)Shifts a front derailleur$380.00780 gmaker’s page2026-07-18Build with this
GRX ST-RX820-LA Shift/Brake Lever (pair, 1x)No front shifting$360.00552 gmaker’s page2026-07-21Build with this
Source

Source: each variant links the maker’s own page in the table above. Last checked 2026-07-18 to 2026-07-21.

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 698 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-RX815 Shift/Brake Lever (pair, 2x, Di2)Next: Shimano 105 ST-R7170 Di2 (pair)All Shimano shifter/brake leversOpen a variant in the builder to see the ones that apply to your own parts