CeramicSpeed OSPW System R9250/R8150The OSPW System R9250/R8150 from CeramicSpeed is an oversized pulley wheel system that is designed and engineered to enhance gear shifting accuracy, efficiency and speed. This version is specifically designed for use with Shimano Dura-Ace 9200 and Ultegra 8100 systems.Chosen by World Champions and top athletes around the world, the CeramicSpeed Oversized Pulley Wheels System has been proven to be the fastest pulley system in the world. Featuring an industry-leading design, this limited-edition model is for Shimano Dura-Ace 9200 and Ultegra 8100 systems with an integrated stop tower for simple installation and durability.This OSPW System has hand built CeramicSpeed Bearings installed in each pulley and it comes with a four-year CeramicSpeed warranty as standard and a lifetime CeramicSpeed warranty when choosing coated bearings (please choose option from the menu).Since its introduction in 2015, the CeramicSpeed Oversized Pulley Wheel System has been through 13 unique derailleur compatibility developments. No other pulley system has the depth of use and trust as the CeramicSpeed OSPW, which counts both Men’s and Women’s Triathlon World Champions, World Tour professional road teams, XCO professional MTB Teams, and elite athletes worldwide as its users. CeramicSpeed Shimano R9250/R8150 OSPW SystemFeaturing a 13-tooth upper pulley wheel and a 19-tooth lower pulley wheel to provide absolute optimisation of the rear derailleur. The upper and lower oversized aluminium pulley wheels come fitted with either standard or coated CeramicSpeed Bearings. Please Note: While there are visual similarities in the 9100 Series OSPW and 9200 Series OSPW, the spring tension settings, rotation stop tower placement, and mounting pin depth are slightly repositioned and as such the systems are not cross-compatible. For 8100 derailleurs, the cage uses the factory derailleur body washer. 9200 derailleurs will require the new included derailleur body washer. Features: Pulley Wheel Material: Aluminium Use: Road Pulley Wheels: CeramicSpeed 13-tooth upper and 19-tooth lower Bearing Options: CeramicSpeed Standard or Coated (choose from the menu) Compatibility: Shimano Dura Ace 9200 and Ultegra 8100 Included: CeramicSpeed Bearing Oil in 15ml dropper bottleTechnologies: The overall power savings of the OSPW System for Shimano Dura-Ace 9200 and Ultegra 8100 reach 30%-60%, or more in some cases, over a stock setup The oversized pulley wheels have 3-5 times longer lifetimes than the commonly used standard pulleys on the marketBuy CeramicSpeed Components from Chain Reaction Cycles, the World’s Largest Online Bike Store.