Rear derailleurs
Shimano Shimano Acera RD-M3020-8 Rear Derailleur
8-speed SGS · 11-34T
Compatibility: reviewed
Known specifications can be used by the compatibility engine.
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Catalog trust
Evidence and freshness
Technical-source dates and retailer offer checks are separate. A retailer check does not validate compatibility.
Report a correction- Technical review
- Aug 13, 2026
- Compatibility review
- Reviewed Aug 13, 2026
Approved technical sources
- Shimano Lifestyle Active rear derailleur specificationsManufacturerSource checked Jul 31, 2026Evidence reviewed Aug 13, 2026
- Shimano current MTB component ordering catalogManufacturerSource checked Jul 29, 2026Evidence reviewed Aug 13, 2026
- Shimano current drivetrain compatibility tablesManufacturerSource checked Jul 29, 2026Evidence reviewed Aug 13, 2026
Technical data
Specifications
- Speeds
- 8-speed
- Supported speeds
- 8-speed
- Maximum cassette cog
- 40T
- Smallest cassette cog
- 11T
- Supported cassette combinations
- 11-34t
- Supported front chainrings
- 3
- Maximum front difference
- 20T
- Drivetrain family
- Shimano MTB/Lifestyle HG mechanical 8-speed
- Compatible chain families
- Shimano HG 8/7/6-speed
- Front drivetrain groups
- Shimano Acera Altus 3x8
- Shift actuation
- Mechanical
- Frame mounting
- Conventional hanger
- Total capacity
- 45T