Genuine Shimano Service Part
The Y3E998010 pulley set is designed as a factory replacement part for specific Shimano rear derailleurs. Genuine pulleys help maintain the intended chain path, pulley spacing, cage clearance and shifting feel.
Guide and Tension Pulley Function
The upper guide pulley helps steer the chain accurately across the cassette, while the lower tension pulley helps manage chain wrap and drivetrain tension. When either pulley becomes worn, shifting can feel noisy, vague or inconsistent.
Precision Tooth Profile
Shimano pulley wheels are shaped to work with the derailleur cage and chain path. The tooth profile helps support smooth chain movement, especially during rear shifts under normal pedalling load.
Bearing / Bushing Support
The pulley set is designed to rotate smoothly under chain load. A worn or gritty pulley can add drivetrain drag, noise and shifting inconsistency, so replacement is a useful part of drivetrain servicing.
Road, Gravel and MTB Versatility
Because this pulley set is listed across compatible Ultegra, GRX and XT derailleurs, it suits a wide range of Australian riding styles, from fast road bunch rides to gravel events and 11-speed trail bikes.
Drivetrain Efficiency Refresh
Fresh pulleys can make an older drivetrain feel smoother and quieter, especially when fitted alongside a clean chain, correctly indexed derailleur and inspected cassette.