Under the hood, the eR9 is identical to its bigger brother: the same wireless protocol, the same seat-tube battery, the same hydraulic calipers with finned cooling pads. The difference? Aluminium brake levers instead of carbon, and an aluminium derailleur cage. A few grams more, a good deal less money – and exactly the same shifting speed and reliability.
The big advantage: the eR9 can be configured for 10, 11 or 12 speeds. Currently riding a 10- or 11-speed road bike? Then you can switch to electronic shifting while keeping your existing wheels, cassette and chain. Want to move to 12 speed later? Just swap the cassette and chain – the groupset carries straight over. That makes the eR9 not only an affordable upgrade, but a future-proof one.
The waterproof battery (IPX7) hides invisibly inside the seat tube and charges over USB-C. Every press of the button delivers an instant, perfectly indexed shift – even under full power on the pedals.
Specifications
- Shifting: wireless electronic, configurable as 2×10, 2×11 or 2×12 speed
- Compatibility: works with 10-, 11- and 12-speed cassettes (11-32T) and chains
- Brakes: hydraulic disc, direct mount, fin-type cooling pads
- Brake levers: aluminium
- Rear derailleur: aluminium cage, cassette range 11-32T
- Front derailleur: direct mount, max. chainring 54T, capacity ≤ 16T
- Battery: seat-tube mounted, 7.4V / 800 mAh, IPX7, USB-C charging
Box contents
- Left shifter, aluminium lever (ST-ER1102-L)
- Right shifter, aluminium lever (ST-ER1102-R)
- Electronic front derailleur (FD-ER1104)
- Electronic rear derailleur (RD-ER1103)
- Front caliper, 160 mm (BR-R04A-160F)
- Rear caliper, 140 mm (BR-R03A-140R)
- Battery + battery tube (BT-ER02)
- USB-C charging cable + power leads
