Rear derailleur parts for the Trek Domane AL 2 Gen 4

Parts menu — 4 parts

• SRAM Universal Derailleur Hanger AC-DRHG-UDH-A1

  Derailleur hanger

  Fit checks required · confidence: single-source Compatibility is not confirmed. Verify the listed mounting requirements before buying or installing this part.

  • Rear thru-axle thread : M12 × 1.0Check your installed setup or its technical sheet.
  • Rear axle threaded portion length : 12.7 mmCheck your installed setup or its technical sheet.
  Why? The facts we compared (3 dimensions compared)

  • Derailleur hanger: bike SRAM UDH (Universal Derailleur Hanger) (single-source) · part SRAM UDH (Universal Derailleur Hanger) — match
  • Rear thru-axle thread (safety-critical): bike nothing on file · part M12 × 1.0 — not on file
  • Rear axle threaded portion length (safety-critical): bike nothing on file · part 12.7 mm — not on file

  Sources:

  • Trek Bicycle — Domane AL 2 Gen 4 · Canada archive SKU 5301345 · specification and size table (tier 1)
  • SRAM — Universal Derailleur Hanger user manual — page 5 installation requirements (tier 1, read 2026-09-28)

  View specifications →

• microSHIFT ADVENT medium-cage clutch rear derailleur, 9-speed

  Rear derailleur

  does not fit · confidence: single-source

  • Rear speeds : 9 speedsDoes not match the documented build.
  • Shift actuation : Mechanical (cable)Check your installed setup or its technical sheet.
  • Rear shifting actuation family : microSHIFT ADVENT 9-speed shifter actuationCheck your installed setup or its technical sheet.
  Why? The facts we compared (3 dimensions compared)

  • Rear speeds: bike 8 speeds (verified) · part 9 speeds — mismatch
  • Shift actuation: bike nothing on file · part Mechanical (cable) — not on file
  • Rear shifting actuation family: bike nothing on file · part microSHIFT ADVENT 9-speed shifter actuation — not on file

  Sources:

  • Trek Bicycle — Domane AL 2 Gen 4 · Canada archive SKU 5301345 · specification and size table (tier 1)
  • Trek Bicycle — Domane AL 2 Gen 4 Canadian family 41587 — exact component service identities and seven-size applicability (tier 1)
  • Shimano — Shimano 2024–2025 specifications v3.2 — exact HG71, RS200, UN300 and R2000-GS tables (tier 1)
  • microSHIFT — ADVENT Medium Cage Clutch Rear Derailleur — RD-M6195M (tier 1, read 2026-08-21)
  • microSHIFT — ADVENT Medium Cage Clutch Rear Derailleur — RD-M6195M (tier 1, read 2026-10-07)
  • microSHIFT — ADVENT Medium Cage Clutch Rear Derailleur — RD-M6195M (tier 1, read 2026-10-07)

  View specifications →

• SRAM GX Eagle rear derailleur, 12-speed

  Rear derailleur

  does not fit · confidence: single-source

  • Rear speeds : 12 speedsDoes not match the documented build.
  • Shift actuation : Mechanical (cable)Check your installed setup or its technical sheet.
  • Rear shifting actuation family : SRAM X-ACTUATION mechanical 12-speedCheck your installed setup or its technical sheet.
  Why? The facts we compared (3 dimensions compared)

  • Rear speeds: bike 8 speeds (verified) · part 12 speeds — mismatch
  • Shift actuation: bike nothing on file · part Mechanical (cable) — not on file
  • Rear shifting actuation family: bike nothing on file · part SRAM X-ACTUATION mechanical 12-speed — not on file

  Sources:

  • Trek Bicycle — Domane AL 2 Gen 4 · Canada archive SKU 5301345 · specification and size table (tier 1)
  • Trek Bicycle — Domane AL 2 Gen 4 Canadian family 41587 — exact component service identities and seven-size applicability (tier 1)
  • Shimano — Shimano 2024–2025 specifications v3.2 — exact HG71, RS200, UN300 and R2000-GS tables (tier 1)
  • SRAM — GX Eagle Rear Derailleur — RD-GX-1-B2 (tier 1, read 2026-10-07)
  • SRAM — GX Eagle Rear Derailleur — RD-GX-1-B2 (tier 1, read 2026-10-07)

  View specifications →

• SRAM Rival eTap AXS rear derailleur, 12-speed

  Rear derailleur

  does not fit · confidence: single-source

  • Rear speeds : 12 speedsDoes not match the documented build.
  • Shift actuation : SRAM AXS (eTap)Check your installed setup or its technical sheet.
  Why? The facts we compared (2 dimensions compared)

  • Rear speeds: bike 8 speeds (verified) · part 12 speeds — mismatch
  • Shift actuation: bike nothing on file · part SRAM AXS (eTap) — not on file

  Sources:

  • Trek Bicycle — Domane AL 2 Gen 4 · Canada archive SKU 5301345 · specification and size table (tier 1)
  • Trek Bicycle — Domane AL 2 Gen 4 Canadian family 41587 — exact component service identities and seven-size applicability (tier 1)
  • Shimano — Shimano 2024–2025 specifications v3.2 — exact HG71, RS200, UN300 and R2000-GS tables (tier 1)
  • SRAM — Rival eTap AXS Rear Derailleur — RD-RIV-E-D1 (tier 1, read 2026-08-21)

  View specifications →