Shimano Ultegra R8150 Di2 12 Speed Rear Derailleur

The Shimano Ultegra R8150 Di2 rear derailleur is part of the Shimano Ultegra R8100 Di2 groupset. Shifting speed has increased by an impressive 58% in the Ultegra R8150 rear derailleur compared to previous Shimano Di2 derailleurs. And it has been optimised even further, especially to improve shifting under load. You'll feel this instantly when standing up on a climb or accelerating for a sprint.

The Ultegra R8100 Di2 groupset is charged easily via the Shimano Ultegra R8150 Di2 rear derailleur with a charging cable which is also used for the new Shimano power meters. The junction box, which was previously mounted in the frame or handlebars, has become redundant. Its technology, with all the adjustment possibilities, has also been integrated into the rear derailleur.

Shimano Di2 app
The Shimano Di2 app can be used for all adjustment options, such as assigning shift buttons, customising shifting ways or adjusting shifting speed. The function of each shift button is customisable. The Synchronized Shift or Semi-Synchronized Shift options, whereby the front derailleur automatically shifts along to ensure the ideal chainline, are still possible.

Semi-wireless connection
The Shimano Ultegra R8100 Di2 Disc 12-speed groupset is a semi-wireless groupset, meaning there is only a cable connection between the front derailleur, rear derailleur and battery. Shifting performance has been taken to an even higher level. Not only has shifting speed increased, you can also shift smoothly while applying power to the pedals now. A junction box is no longer needed; the groupset can be adjusted and charged via the rear derailleur. A fully charged battery will last for some 1000 km before needing to be recharged.