how to replace shimano hydraulic brake hose | Passionhose

Hydraulic disc brakes have become increasingly popular in the cycling world due to their superior stopping power and modulation. However, like any other component on a bike, the brake hoses may need to be replaced over time due to wear and tear, damage, or upgrading to a different length. In this article, we will guide you on how to replace Shimano hydraulic brake hoses, a common task for many cyclists.

Gathering Necessary Tools and Supplies

Before starting the replacement process, you will need to gather the necessary tools and supplies. These include a set of Allen keys, cable cutters, needle-nose pliers, Shimano hydraulic brake hose kit, Shimano hydraulic brake fluid, a bleed kit (optional), and rags to clean up any spills. Ensure you have all these items within arm's reach before starting the procedure to avoid any interruptions.

Removing the Old Hose

The first step in replacing a Shimano hydraulic brake hose is removing the old hose from the brake lever and caliper. To do this, you will need to release the tension on the brake system by pushing the pistons back into the caliper. Use a plastic tire lever or a pad spreader tool to gently push the pistons back while being cautious not to damage the brake pads. Once the pistons are pushed back, remove the retaining bolt that holds the hose in place at the caliper and the lever. Make sure to catch any brake fluid that may leak out during this process using a rag.

Installing the New Hose

With the old hose removed, it's time to install the new Shimano hydraulic brake hose. Start by threading the new hose through the frame or fork, following the same routing as the old hose. Be sure to use the necessary olive and barb inserts provided in the Shimano hose kit to secure the hose to the lever and caliper. Tighten the hose fittings to the recommended torque using a torque wrench to ensure a secure connection that won't leak under pressure.

Bleeding the Brake System

After installing the new hose, it is essential to bleed the brake system to remove any air bubbles that may have entered the system during the installation process. Shimano recommends using their specific bleed kit for this procedure, which includes a funnel, hose, and mineral oil. Follow the manufacturer's instructions on how to bleed Shimano hydraulic brakes carefully to avoid any issues with brake performance. Once the system is properly bled, test the brakes to ensure proper function before riding.

Trimming and Adjusting the Hose Length

Once the brake system has been bled and tested, you may need to trim the new hose to the desired length. Use cable cutters to cut the hose cleanly and precisely, making sure to leave enough length for future adjustments. Reinstall the hose fittings and secure them to the lever and caliper, making sure everything is tight and properly aligned. Test the brakes again to ensure they function correctly after trimming the hose length.

In conclusion, replacing Shimano hydraulic brake hoses is a straightforward procedure that can be done at home with the right tools and knowledge. By following the steps outlined in this article, you can maintain your hydraulic disc brakes in top condition and ensure optimal braking performance on your bike. Remember to take your time, follow the manufacturer's instructions, and double-check your work to avoid any issues with the brake system. Happy riding!