Shimano Disc Dual Control Lever Oil Diaphragm

1. Úvod

This manual provides essential information for the proper installation, maintenance, and troubleshooting of the Shimano Disc Dual Control Lever Oil Diaphragm. This component is crucial for the hydraulic performance of your bicycle's disc brakes, ensuring a sealed system and consistent braking power. Please read these instructions carefully before proceeding with any work on your brake system.

2. Konec produktuview

The Shimano Oil Diaphragm is a precision-engineered replacement part designed to maintain the integrity of your hydraulic disc brake dual control lever's reservoir. It prevents air from entering the system and helps manage fluid expansion and contraction, ensuring reliable brake performance. These diaphragms are manufactured in Japan to Shimano's high-quality standards.

Note on Packaging: Individual diaphragms (less than 10 pieces) may not come in original retail packaging.

3. Kompatibilita

This oil diaphragm is compatible with the following Shimano Disc Dual Control Lever models:

• ST-4720
• ST-4725
• ST-R7020
• ST-R7025
• ST-R8020
• ST-R8025
• ST-R9120
• ST-R7120
• ST-RX400
• ST-RX600
• ST-RX810
• ST-RX820

Please ensure you select the correct diaphragm (left or right) for your specific lever model. The part numbers are Y0C578000 for the left lever and Y0C678000 for the right lever.

4. Instalace/Nastavení

Replacing the oil diaphragm requires careful attention to detail. It is recommended to have basic bicycle maintenance knowledge and appropriate tools. Always refer to the official Shimano dealer manual for your specific lever model for detailed instructions, especially regarding brake bleeding.

Požadované nástroje a materiály:

• New Shimano Oil Diaphragm (Y0C678000 for right, Y0C578000 for left)
• Small Phillips head screwdriver or appropriate hex key (for cover screws)
• Clean rags or paper towels
• Shimano Mineral Oil
• Brake bleed kit (optional, but recommended for post-installation bleed)

Kroky instalace:

1. Připravte si pracovní prostor: Ensure your bicycle is stable and the work area is clean. Protect painted surfaces from brake fluid.
2. Access the Reservoir: Carefully remove the hood cover of your dual control lever to expose the brake fluid reservoir and its cover plate.
3. Identify Diaphragm Location: The diaphragm (labeled as part 18 in the diagram below) is located beneath the reservoir cover plate.
4. 

   Obrázek 1: Rozložené view of a Shimano Dual Control Lever. The oil diaphragm is indicated by the red box and labeled as part 18.
5. Odstraňte starou membránu: Unscrew the small screws holding the reservoir cover plate in place. Carefully lift the cover plate and remove the old diaphragm. Be prepared for a small amount of brake fluid to be present.
6. 

   Figure 2: New oil diaphragm shown with its cover plate and mounting screws. Note the 'SHIMANO MINERAL OIL' label on the cover.

7. Vyčistěte nádržku: Gently clean the reservoir area and the underside of the cover plate with a clean rag. Ensure no debris or contaminants are present.
8. Instalace nové membrány: Place the new oil diaphragm into the reservoir, ensuring it sits flush and correctly oriented. The diaphragm has a specific shape to fit the reservoir.
9. 

   Obrázek 3: Nahoře view of the Shimano oil diaphragm.

10. 

    Obrázek 4: Spodní část view of the Shimano oil diaphragm.
11. Reattach Cover Plate: Carefully place the reservoir cover plate back over the diaphragm, aligning the screw holes. Tighten the screws evenly until snug, but do not overtighten.
12. Odvzdušnění brzdového systému: After replacing the diaphragm, it is highly recommended to perform a full brake bleed to remove any air that may have entered the system and to ensure optimal brake performance. Follow Shimano's official bleeding procedure for your specific brake model.
13. Reinstall Hood Cover: Once the brake system is bled and functioning correctly, reinstall the lever hood cover.

5. Údržba

Regular inspection of your hydraulic brake system, including the dual control levers, is essential for safety and performance. Check for:

• Úniky kapalin: Any visible oil around the lever body or reservoir cover may indicate a compromised diaphragm or seal.
• Pocit brzdění: A spongy or inconsistent brake lever feel can be a sign of air in the system, which could be related to a faulty diaphragm.
• Fyzické poškození: Inspect the diaphragm and cover for any cracks, tears, or deformation.

Replace the diaphragm immediately if any signs of wear, damage, or leakage are observed. Always use genuine Shimano replacement parts and mineral oil.

6. Řešení problémů

If you experience issues with your hydraulic disc brakes after diaphragm replacement, consider the following:

• Loss of Brake Pressure / Spongy Lever: This is most commonly caused by air in the hydraulic system. A thorough brake bleed is usually required. Ensure the diaphragm is seated correctly and the reservoir cover is sealed.
• Oil Leakage from Lever: Check that the diaphragm is installed correctly and is not pinched or damaged. Ensure the reservoir cover screws are tightened appropriately. If leakage persists, the diaphragm or other seals may be faulty.
• Brake Not Engaging: Verify that the brake pads are not excessively worn and that the caliper is functioning correctly. Ensure sufficient brake fluid is in the system and that it has been properly bled.

If problems persist, consult a professional bicycle mechanic or contact Shimano customer support.

7. Specifikace

8. Uživatelské tipy

• Correct Part Selection: Always double-check that you are ordering the correct diaphragm for your specific lever model and side (left or right). The part numbers Y0C578000 (Left) and Y0C678000 (Right) are crucial.
• Brake Bleed is Key: After replacing the diaphragm, a proper brake bleed is almost always necessary to ensure optimal performance and to remove any trapped air.
• Originální díly: Use only genuine Shimano mineral oil and replacement parts to ensure compatibility and system integrity.
• Not a Brake Pump: This diaphragm is a component of the brake lever's reservoir, not the entire brake pump or caliper. Ensure you are replacing the correct part for your issue.

9. Záruka a podpora

For warranty information or technical support, please refer to the official Shimano website or contact your authorized Shimano dealer. Keep your purchase receipt as proof of purchase.