Shimano Tiagra 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. 930 produced no finding of any kind; that is Tiagra ST-R4020-L (left/front). Tiagra ST-R4020-R (right/rear) clears 884. Each variant produces 71 to 117 distinct errors and 0 distinct warnings.
Will not fit
- Will not fiterror · CassetteSpeed mismatch: Shifter 11s, Cassette 12s. The drivetrain must share one speed count. On 23 of the 34 verified cassettes in this catalog. Applies to all 2 variants.
- Will not fiterror · Rear DerailleurSpeed mismatch: Shifter 11s, Rear derailleur 12s. The drivetrain must share one speed count. On 17 of the 29 verified rear derailleurs in this catalog. Applies to all 2 variants.
- Will not fiterror · CassetteDrivetrain mismatch: Shifter = shimano-road-11, 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-road-11, 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.
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 5 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 3 of the 34 verified cassettes each.
Rg drivetrain system, Front Derailleur. 7 more findings from the same check, on up to 6 of the 22 verified front derailleurs each.
Rg drivetrain speeds, Cassette. 4 more findings from the same check, on up to 3 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.
Rg brake system, Front Caliper. 1 more finding from the same check, on up to 6 of the 35 verified calipers each.
Rg brake system, Rear Caliper. 1 more finding from the same check, on up to 6 of the 35 verified calipers each.
Open a variant in the builder to see the ones that apply to your own parts.
$208.00 MSRP
What the maker states
- System
- Drivetrain system shimano-road-11
- Speeds
- 11-speed (rear index count the maker rates it for)
- Actuation
- Mechanical
- Brake system
- Disc-hydraulic
- Side
- Left side (on 1 of 2 variants); Right side (on 1 of 2 variants)
- 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
| Variant | Side | Front shift | Price (MSRP) | Weight | Source | Last checked | Build |
|---|---|---|---|---|---|---|---|
| Tiagra ST-R4020-L (left/front) | Left side | Shifts a front derailleur | $208.00 | not stated | maker’s page | 2026-08-20 | Build with this |
| Tiagra ST-R4020-R (right/rear) | Right side | No front shifting | $208.00 | not stated | maker’s page | 2026-08-20 | Build with this |
Source
Source: each variant links the maker’s own page in the table above. Last checked 2026-08-20.
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.
- 3T Aeroflux Integrale (Handlebar) No conflicts found
- 3T Apto Stealth Stem (Stem) No conflicts found
- 3T Superergo LTD (standard, non-INTEGRALE) (Handlebar) No conflicts found
- All-City Zig Zag Frameset (Frame) No conflicts found
- Argon 18 SUM D-Shape Seatpost (Seatpost) No conflicts found
- Argon 18 Sum Frameset (Frame) No conflicts found
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.