Congratulations! If you are searching for this XTR RD-M9000 Derailleur Pulley Set that means you have been logging crazy miles on your XTR M9000 or M9050 equipped bike. It takes quite a bit of riding and some gritty conditions to wear these composite pulleys down. It is actually amazing how well these lightweight (18g) pulleys wear and tolerate constant use while pedaling, with very low friction. Most riders and mechanics will see visual wear first in the lower Guide pulley, and when that wear is clear, potentially affecting chain performance, it is best to replace both pulleys. Even if you can't see the obvious wear on the upper pulley, it will be be found in wear on the shoulders of the teeth, not in the teeth themselves.

This replacement set includes the two pulley wheels: Guide and Tension. Both have excellent mud clearing properties, feature 11 teeth, precision sealed bearing assemblies, and are directional, but are not interchangeable. The Guide pulley (upper) features cut-outs and has sharper looking teeth that offer excellent chain wrap and guidance that are essential as you shift up and down the cassette. The Tension pulley (lower) has shorter, thicker teeth that are designed for long wear and efficiency under the heavy spring tension delivered by your M9000 /M9050 rear derailleur, especially when the clutch is engaged. Keep your premium drivetrain running properly at all times. This XTR RD-M9000 Derailleur Pulley Set is crucial to overall performance, so when you clean your drivetrain or inspect your bike, pay attention to the details.