Smooth, clean and precise gear shifts are exactly what you will get out of Shimano's flagship XTR RD-M9100 11/12 Speed Rear Derailleur. The derailleur meets the demands of Trail and XC, Enduro and Marathon racers with its awesome aesthetic, attention to detail, reliability and material choice. It is now lighter, quieter, more durable and more versatile than the previous generation.

Shimano redesigned these from the ground up and have made a number of changes, one of which features bigger 13-tooth pulleys(Mid Cage GS), as well as improved ground clearance with Shimano’s proven Shadow RD+ low profile technology.

Compatible with 11 and 12-speed drivetrains. The RD-M9100 is specifically designed to work with the XTR 1x drivetrain, unlike the RD-M9120 derailleur which is best for a 2x setup.

Features:

• Optimized for Shimanos latest drive system. 10-45T (12-speed) and 10-45T (11-speed)
• Decreased rear derailleur tension at low gear position, to prevent high chain tension at low gear
• Add bumper at rear derailleur pulley cage for silent drive
• Bigger 13T pulley
• 10-51T (12-speed) (Long Cage SGS)
• 28 mm better ground clearance (vs. RD-M9100-SGS)
• Enhanced shifting performance
• Low sprocket combination
• Silent drivetrain
• Low profile design

Mid Cage - RD-M9100-GS Specs:

• Model:RD-M9100-GS
• Series:XTR M9100 Series
• Weight 237g
• Low sprocket Max. 45T
• Low sprocket Min.45T
• Sealed Bearing Pulleys
• Pulley Teeth: 13T
• Pulley cage: GS
• Rear speeds:11 (Wide flange) / 12
• Top sprocket Max: 10T
• Top sprocket Min:10T
• Total capacity35T

Long Cage - RD-M9100-SGS Specs:

• Model:RD-M9100-SGS
• Series:XTR M9100 Series
• Weight: 240g
• Low sprocket Max: 51T
• Low sprocket Min:45T
• Sealed Bearing Pulley
• Pulley Teeth: 13T
• Pulley cage: SGS
• Rear speeds12
• Top sprocket Max: 10T
• Top sprocket Min:10T
• Total capacity:41T