Shimano Dura-Ace RD-R9100 Pulley Set

Shimano rear-derailleur pulley set for the named series — the two small toothed wheels that route the chain through the rear derailleur cage. The upper (guide) pulley sets shift-feel; the lower (tension) pulley keeps chain tension. Both are wear-parts on a high-mileage drivetrain and a service-kit replacement. Dura-Ace is Shimano's top-tier road groupset — the same parts the WorldTour peloton runs. Weight-optimised, finished to the tightest tolerances in the range. This is the Shimano Dura-Ace RD-R9100 Pulley Set.