Riders with Ultegra 6800 or 6870 Di2 rear derailleurs whose pulleys are worn or noisy.
Worn jockey wheels are an easy thing to miss: the teeth get pointy, the bearings get gritty, and the drivetrain starts to sound rough. This Shimano Y5YC98140 set replaces both the guide (upper) and tension (lower) pulleys.
It is the factory part for Ultegra RD-6800 and Ultegra Di2 RD-6870 11 speed rear derailleurs, so it fits the cage exactly and shifts the way Shimano intended. Both pulleys run on sealed bearings to keep grit out.
A good job to do alongside a new chain and cassette, or whenever the old pulleys feel notchy when you spin them by hand.
Genuine Shimano
Factory replacement for RD-6800 and RD-6870.
Both pulleys
Guide and tension pulley in one set.
Sealed bearings
Keeps grit and water out.
Quieter drivetrain
Restores smooth, crisp shifting.
Pulley set
Compatibility
Factory replacement
Genuine Shimano pulleys made for the RD-6800 cage, so fit and shifting are exactly as designed.
Great for
Maybe not for
Check the model number on your rear derailleur: this set is for RD-6800 and RD-6870. The guide and tension pulleys are different, so note which goes where before removing the old ones.
Do one pulley at a time
Swap one pulley, then the other, so you never mix up the upper and lower positions or the washers. Threadlocker on the bolts is a good idea.
Spin test
Spin your old pulleys by hand. If they feel gritty or have side-to-side play, or the teeth look pointed, it is time for new ones.
The drivetrain on most of the world's bikes.
Shimano was founded in Sakai, Japan in 1921 and started out making freewheels.
It is now the world's largest maker of bicycle components, from entry-level Tourney parts to Dura-Ace race groupsets.
