CeramicSpeed OSPW RS Alpha Pulley Wheel for Shimano 7150

CeramicSpeed OSPW RS Alpha Pulley Wheel for Shimano 7150 is an oversized pulley system for riders using Shimano 105 R7150 who want a lower-friction rear derailleur setup with greater protection against contamination. The RS Alpha version combines CeramicSpeed’s oversized pulley concept with its Alpha Disc design, replacing an open-spoke pulley structure with a solid disc and separate composite tooth profile. Compared with CeramicSpeed’s 5-spoke RS option, the Alpha Disc version places more emphasis on debris protection, durability and reduced chain noise.

Designed for Durability. The Alpha Disc uses a solid aluminium centre with a separate narrow-wide composite tooth profile. CeramicSpeed states that this construction improves wear protection and reduces noise while preventing external objects from becoming trapped between pulley spokes. The cage has also been reinforced compared with earlier OSPW designs, while adjustable spring tension allows the system to be tuned for the derailleur setup.

Check Derailleur Compatibility. This version is intended specifically for Shimano 105 R7150. It replaces the original rear-derailleur cage and pulley assembly as a complete system and is intended for road and triathlon use. Installation should follow CeramicSpeed’s dedicated Shimano OSPW RS procedure, including correct spring-tension selection and derailleur adjustment. Riders should confirm the exact rear-derailleur model before fitting rather than assuming compatibility with other Shimano electronic groupsets.