Shimano RD-R9250 Dura Ace 12-speed Di2 E-tube Rear Derailleur

Features:

• The rear derailleur is now the brains of the system with wireless connectivity to the shifters. It acts as the point the system is charged, provides Ant+ connection to 3rd party devises and replaces the handlebar junction
• Button on the derailleur for Di2 operations, and led light denotes synchronized shift mode, setting mode and charge requirements
• Programmed automatic motion at the touch of a switch makes this derailleur quick, smooth and effortless to shift
• Synchronized shift designed, developed to choose the next biggest or lowest gear ratio irrespective of whether a gear change needs to be made by the front or rear derailleur
• The removal of traditional mechanical cables in favour of electrical wires not only eliminates poor shifting caused by contaminates, corrosion and stretching
• Low profile shadow derailleur design
• Derailleur contains a saver (fuse) function, where the inner structure is protected from strong impacts
• 11-34t wide gear ratio capacity will cater for compact setups as well as the traditional road double
• Full carbon fibre inner and outer pulley plates enhance rigidity and reduce weight
• Titanium b axle bolt for further weight savings
• High tolerance cold forged aluminium link plates and body construction is extremely light and durable
• Four self-lubricating micro-machined fluorine-coated link pivot bushings provide low-friction shifting
• Pulleys are made of tough dupont zytel for longer life and less chain noise
• 12-speed e-tube Di2 compatible