Dura-Ace Di2 rear mech
Shimano Dura-Ace RD-R9250 Di2 Rear Derailleur
The heart of the semi-wireless Dura-Ace R9200 system: a 12-speed Di2 rear mech that houses the charging port and wireless unit, and shifts noticeably quicker than any Shimano mech before it. One cage covers 11-28T through to 11-34T cassettes.
Highlights
Why we rate it
Brain of the system
Wireless receiver, charging port, LED status light and function button all live in the mech, so there is no separate junction box or wireless unit to fit.
Quicker shifting
A stronger motor and revised linkage cut rear shift times significantly over the previous 11-speed Dura-Ace Di2 mech.
One cage for every cassette
A single cage length handles everything from tight 11-28T race cassettes up to 11-34T climbing ratios, which keeps stocking and spares simple.
Carbon cage plates
The carbon-reinforced pulley cage keeps weight down while staying stiff enough for crisp, accurate indexing.
Impact protection
A built-in saver clutch lets the motor gearbox give way in a crash rather than strip, protecting the internals.
Tech specs
Specification
Manufacturer specification. Details may change without notice.
Specification
- Model code
- RD-R9250
- Speeds
- 12
- Actuation
- Di2 (semi-wireless, battery-in-frame)
- Max low sprocket
- 34T
- Min low sprocket
- 28T
- Top sprocket
- 11T
- Cage
- Single length, Shadow RD, carbon cage plates
- Pulleys
- 11T with cartridge bearings
- Ports
- 1 x EW-SD300 E-Tube, 1 x charging port
- Chain
- Shimano HG 12-speed
- Weight
- 215g (claimed)
- Compatible levers
- ST-R9270 (wireless)
Ordering
Available from The Cycle Collective
Available to order through The Cycle Collective in Dorking. For availability, setup or advice, call 0203 148 6764 or email hello@thecyclecollective.cc.