OSPW RS ALPHA for Shimano 9250/8150

The OSPW RS ALPHA takes the efficiency of CeramicSpeed's oversized pulley system and adds an extra layer of "bombproof" engineering. The defining feature is the ALPHA Disc Pulley Wheel, which utilizes a two-piece construction: a separate narrow-wide composite tooth profile for noise reduction and long wear, paired with a solid aluminum disc. This solid disc design prevents sticks, mud, or debris from getting caught in the spokes—a technology born from professional CycloCross racing. Combined with the Active Debris Remover (ADR) dust covers and a reinforced cage, the RS ALPHA is the most resilient electronic shifting upgrade available for Dura-Ace and Ultegra 12-speed drivetrains.

Key Features

• ALPHA Disc Technology: The solid disc design eliminates the potential for external objects to snag in the pulleys while providing superior lateral stiffness for crisp shifting.

   

• Active Debris Remover (ADR): A patent-pending bladed groove structure that dynamically flings contaminants away from the bearings while the pulley rotates.

   

• Composite Tooth Profile: The teeth are made from a unique fiber-reinforced composite that is quieter and longer-wearing than traditional alloy teeth.

   

• Modern Faceted Cage: A reinforced, angular cage design that is significantly stiffer than previous OSPW models to handle high-torque efforts.

   

• Handbuilt Ceramic Bearings: Features CeramicSpeed’s signature hybrid ceramic bearings, offering a lifetime warranty when the ADR technology is present.

   

Specifications

• Compatibility: Shimano Dura-Ace RD-9250 and Ultegra RD-8150 (12-speed Di2)

   

• Pulley Material: Solid Aluminum Disc with Composite Teeth

   

• Cage Material: Carbon fiber reinforced PA

   

• Bearing Type: Coated or Standard Ceramic Options

• Max Cassette Size: 34T

   

Typical Components Included

• Complete OSPW RS ALPHA System (Cage + ALPHA Disc Pulley Wheels)

   

• CeramicSpeed Pulley Oil (15ml)

   

• Mounting and maintenance instructions