In this article I will share my thoughts about the CEMA Bearing Ceramic Pulley Wheels Shimano 12-14T that I’ve installed on the Shimano Ultegra R8170 rear derailleur of the Canyon Ultimate CF SLX 8.0 Di2. These 12 speed Rear Derailleur Ceramic Pulley Wheels were discounted, so an easy replacement despite not having a full ceramic bearing.
