Short Cage Rear Deraileur (10 speed)

Short Cage Rear Deraileur (10 speed)

Ultegra RD-6770-SS

This RD-6770 rear derailleur is a 10-speed rear derailleur and as such it isn't really used anymore. All current and previous Di2 generations have moved on to 11-speed and 12-speed.

Its low sprocket max is 28T and the top sprocket min is 11T. The max supported front difference is 16T and its total capacity is 33T.

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Has your RD-6770 broken? You cannot just replace that with an 11-speed model - all installed derailleurs must be the same speed.

Read more on upgrading your bike and compatibility on the pages linked below.


  • Model code: RD-6770-SS
  • Series: Ultegra (6770)
  • Weight: 270g
  • Speeds: 10
  • SD50 ports: 1
  • Max front difference: 16T
  • Total capacity: 33T
  • Low sprocket max: 28T
  • Low sprocket min: 23T
  • Top sprocket min: 11T
  • Top sprocket max: 12T
  • Pulley teeth: 11
  • Mount:
  • RD type: Non-shadow RD
  • Clutch: No

Related components

View the Dual Control Lever (ST-6770)


Dual Control Lever

View the Front derailleur (2x10) (FD-6770)


Front derailleur (2x10)

View the Junction and Wire Harness (deprecated) (SM-EW67-A-E)


Junction and Wire Harness (deprecated)

View the External Battery (SM-BTR1)


External Battery

Related pages