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Shimano CUES RD-U4000 GS Rear Derailleur

What the checker says51will not fit

Run variant by variant through the e-MTB 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 442 verified e-MTB parts in this catalog. 338 produced no finding of any kind; that is CUES RD-U4000 GS 9-speed. CUES RD-U4020 clears 334. Each variant produces 39 to 44 distinct errors and 0 distinct warnings.

Will not fit

  • Will not fiterror · CassetteSpeed mismatch: Derailleur 9s, Cassette 12s. Shifter, derailleur and cassette must be the same speed count. On 30 of the 58 verified cassettes in this catalog. Applies to all 2 variants.
  • Will not fiterror · ShifterSpeed mismatch: Shifter 12s, Derailleur 9s. Shifter, derailleur and cassette must be the same speed count. On 28 of the 53 verified shifters in this catalog. Applies to all 2 variants.
  • Will not fiterror · ShifterDrivetrain mismatch: Shifter = shimano-12, Derailleur = shimano-linkglide. Shifter, derailleur and cassette must be one system. On 19 of the 53 verified shifters in this catalog. Applies to all 2 variants.
  • Will not fiterror · CassetteDrivetrain mismatch: Derailleur = shimano-linkglide, Cassette = shimano-12. Shifter, derailleur and cassette must be one system. On 14 of the 58 verified cassettes in this catalog. Applies to all 2 variants.
  • Will not fiterror · CassetteCassette too big: 52T cassette exceeds the Shimano CUES RD-U4000 GS 9-speed max of 46T. On 13 of the 58 verified cassettes in this catalog. Applies to 1 of 2 variants.
  • Will not fiterror · CassetteCassette too big: 52T cassette exceeds the Shimano CUES RD-U4020 max of 36T. On 13 of the 58 verified cassettes in this catalog. Applies to 1 of 2 variants.

Emtb cassette capacity, Cassette. 11 more findings from the same check, on up to 11 of the 58 verified cassettes each.

Emtb drivetrain system, Shifter. 11 more findings from the same check, on up to 6 of the 53 verified shifters each.

Emtb drivetrain system, Cassette. 9 more findings from the same check, on up to 9 of the 58 verified cassettes each.

Emtb actuation, Shifter. 6 more findings from the same check, on up to 1 of the 53 verified shifters each.

Emtb drivetrain speeds, Cassette. 4 more findings from the same check, on up to 11 of the 58 verified cassettes each.

Emtb drivetrain speeds, Shifter. 4 more findings from the same check, on up to 10 of the 53 verified shifters 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.

$28.00 to $60.00 MSRP·300 to 330 g

What the maker states

System
Drivetrain system Shimano LinkGlide (CUES)
Speeds
9-speed (rear index count the maker rates it for)
Actuation
Mechanical (cable)
Mount
Standard hanger
Maximum cog
Largest cog 36 teeth (on 1 of 2 variants); Largest cog 46 teeth (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

VariantMaximum cogPrice (MSRP)WeightSourceLast checkedBuild
CUES RD-U4000 GS 9-speedLargest cog 46 teeth$60.00330 gmaker’s page2026-07-13Build with this
CUES RD-U4020Largest cog 36 teeth$28.00300 gmaker’s page2026-08-19Build with this
The rest of what the maker states2 not published

2 further fields the checker looks for are not published by Shimano, so we leave them blank rather than estimate them, and those 2 checks stay silent on this rear derailleur. They are maximum cog top and total capacity. Each is recorded as “not stated by the maker (not checked)”.

Source: each variant links the maker’s own page in the table above. Last checked 2026-07-13 to 2026-08-19.

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 227 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 CUES RD-U3020Next: Shimano CUES RD-U4010All Shimano rear derailleursOpen a variant in the builder to see the ones that apply to your own parts