42810-04B Rear Brake Master Cylinder Repair Kits

This Cycle Pro LLC rear brake master cylinder repair kit is a comprehensive solution for rebuilding your Sportster's braking system. Replacing OEM 42810-04B, the kit includes all the necessary internal seals and components to refresh a worn-out master cylinder. It works with DOT 3, DOT 4, or DOT 5 brake fluids, though it is vital to use the same fluid type already in your system to prevent damage. This kit is designed for Sportster models and fits both ABS and non-ABS versions unless otherwise specified. Before ordering, verify if your bike uses a remote or integrated fluid reservoir, as these internal kits are specific to the reservoir style and are not interchangeable.