CeramicSpeed's OSPW pulley system offers real overall friction advantages, but some cyclists choose to keep their stock pulley cage and simply upgrade the pulley wheels. The 12-tooth narrow-wide design on these machined aluminum CeramicSpeed pulleys decreases chain articulation and ensures a crisp but smooth chain engagement on-to and off-of each pulley, moving on and off pulleys without additional drag.

Of course the focus of CeramicSpeed's rise to glory has been the Silicon Nitride balls they use in the hardened steel races to offer real reduction in friction within in the drivetrain. The Grade 3 balls add longevity as well. Keep in mind you do need to service and lubricate these bearings per the instructions to keep them rolling smoothly and gain the long-life. The process is simple and CeramicSpeed includes their lubricating oil.

These 12-tooth pulleys are developed, designed and handbuilt in Denmark and come with separate dust covers to fit 9100, R8000, RX, GRX, XT and XTR series 11-speed derailleurs.