How to find the right Bike Derailleurs AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Bike Derailleurs
- Speed count match
- The derailleur, shifter, cassette and chain must all be the same number of speeds (for example all 11-speed). A derailleur built for a different speed count will not index cleanly with your shifter and cassette.
- Cable pull or ecosystem match
- Keep the derailleur in the same brand and family as the shifter: Shimano road, Shimano MTB, SRAM road, SRAM MTB (Exact Actuation), Campagnolo, or microSHIFT. For wireless or electronic, it must be the same protocol (SRAM AXS or Shimano Di2). Each family moves the derailleur a different distance per click, so mixed pairs mis-shift even when the speed count matches.
- Mount standard
- Fronts: match the frame's braze-on, clamp diameter, or direct mount. Rears: match a standard hanger, Shimano direct mount, or the SRAM UDH direct-to-frame mount. The wrong mount either will not attach or puts the derailleur in the wrong position.
- Capacity and gear range
- Check the derailleur's rated maximum cog or chainring size and its total capacity against your actual drivetrain. Going over the rated capacity causes slack or overstretched chain and poor shifting.
- Mechanical vs electronic
- Electronic and wireless derailleurs only work with their matching shifters and batteries. Mechanical derailleurs need a cable-actuated shifter from the same family. You cannot run an electronic derailleur off a cable shifter, or the reverse.
Brands that matter
- Shimano: Widest range, from Tourney to Dura-Ace and XTR, including GRX gravel and Cues; mind the road vs MTB pull differences.
- SRAM: Road and MTB mechanical plus AXS wireless; MTB uses its own Exact Actuation pull.
- Campagnolo: Road and Ekar gravel groups; only compatible with Campagnolo shifters.
- microSHIFT: Budget-to-mid groups such as Advent X; pair it with microSHIFT shifters.
- Box Components: Mountain-focused 1x drivetrains with their own shifters.
- L-TWOO: Low-cost road and gravel groups, mostly matched to their own shifters.
What to avoid
- Mixing derailleur and shifter brands or families on the strength of matching speed counts alone.
- Replacing a derailleur before checking whether the hanger is bent, a frequent cause of bad shifting after a crash.
- Generic no-name derailleurs with no stated speed count or pull compatibility.
Questions
Can I put a SRAM derailleur on Shimano shifters?
Generally no. Cassettes of the same speed count often cross over, but keep the shifter and derailleur in one brand and family.
Will an 11-speed derailleur work with my 10-speed shifter?
Usually not. Indexing depends on both speed count and pull ratio, so buy the derailleur listed for your shifter's speed and family.