Disc brakes are a critical component of your bike, offering the stopping power and reliability needed for a safe and enjoyable ride. However, the Shimano BR-R7170 [paid link] disc brakes, like any other brake system, can sometimes experience issues such as squealing or noisy braking. If you’re hearing unpleasant sounds during braking, it’s important to diagnose and fix the issue promptly to maintain optimal performance and rider safety.

In this guide, we’ll cover common causes of noise or squealing with the Shimano BR-R7170 [paid link], and provide a step-by-step approach to resolve these issues.

Understanding the Cause of Noisy or Squealing Shimano BR-R7170 Disc Brakes

Before we dive into solutions, it’s crucial to understand what can cause noise with your Shimano BR-R7170 [paid link] disc brakes. The following factors often contribute to noisy or squealing brakes:

1. Contaminated Brake Pads or Rotors

Oil, dirt, or other contaminants can easily accumulate on the brake pads or rotors, leading to squealing or reduced braking performance. This is one of the most common causes of brake noise.

2. Improper Pad Alignment

Incorrect pad alignment with the rotor can cause the pads to contact unevenly or not fully engage the rotor, leading to noise.

3. Glazed Brake Pads

Brake pads can become glazed due to excessive heat or improper bedding. Glazing causes the pads to become smooth, resulting in poor braking performance and noise.

4. Rotor Warping or Misalignment

If the rotor is warped, bent, or improperly aligned, it may rub against the pads inconsistently, producing noise. This can also negatively affect your braking efficiency.

5. Improper Bedding-In Process

New brake pads and rotors require a proper bedding-in process to transfer an even layer of brake pad material onto the rotor. If this process isn’t performed correctly, it can result in squealing sounds.

Step-by-Step Guide to Fix Noisy Shimano BR-R7170 Disc Brakes

Now that we know the potential causes of squealing, let’s explore how to diagnose and fix each issue with your Shimano BR-R7170 disc brakes.

Step 1: Inspect and Clean the Brake Pads and Rotors

The first step is to ensure the brake pads and rotors are clean and free from contaminants. Any oil, dirt, or grime on the brake components can cause significant noise.

Tools Required:

• Isopropyl alcohol (preferably 70% or higher)
• Clean rags or paper towels
• A soft brush (optional)

Instructions:

1. Remove the wheels from your bike to gain easy access to the brake system.
2. Inspect the brake pads for signs of contamination such as oil or dirt. If the pads appear contaminated, clean them using isopropyl alcohol and a clean rag. Avoid touching the pad surface with your fingers as oils from your skin can transfer onto the pads.
3. Use a clean rag or paper towel soaked with isopropyl alcohol to wipe down the rotors. Make sure to clean both sides of the rotor.
4. Check the rotors for any signs of damage or excessive wear. If you notice significant scoring or glazing, you may need to replace them.

Step 2: Check Brake Pad Alignment

Misaligned brake pads can cause uneven contact with the rotor, leading to squealing. To fix this issue, you’ll need to adjust the pad alignment.

Instructions:

1. Check that the brake pads are positioned evenly on both sides of the rotor. If one pad is closer to the rotor than the other, the braking force will be uneven, resulting in noise.
2. Using a 2mm or 3mm Allen wrench [paid link] (depending on your Shimano BR-R7170 caliper), adjust the pad alignment by loosening the caliper mounting bolts and shifting the caliper to center it over the rotor.
3. Tighten the bolts back up once the alignment is corrected.
4. Spin the wheel and ensure that there is no contact between the pads and rotor when the brake lever is not being squeezed.

Step 3: Inspect for Glazed Brake Pads

Glazed brake pads can produce a high-pitched squeal due to their smooth, shiny surface. If your brake pads appear glazed, they may need to be sanded down or replaced.

Instructions:

1. Inspect the surface of the brake pads. If you notice a shiny, smooth surface, they may be glazed.
2. To remedy this, lightly sand the pads with fine-grit sandpaper (around 180-220 grit) to remove the glazed layer. Sand in a circular motion to avoid creating uneven surfaces.
3. After sanding, clean the pads with isopropyl alcohol to remove any debris or dust created during sanding.

Step 4: Check Rotor Alignment and True

Warped or misaligned rotors can also cause noise by rubbing against the brake pads unevenly. To fix this, you’ll need to inspect the rotor for any signs of warping or misalignment.

Instructions:

1. Spin the wheel and carefully observe the rotor. If the rotor wobbles or moves side-to-side, it may be warped or bent.
2. If the rotor is slightly warped, you can use a rotor truing tool or a flat tool (such as a wrench) to carefully straighten it. Apply gentle pressure on the areas that are out of true.
3. For more significant warping, you may need to replace the rotor entirely.
4. Once the rotor is true, recheck the alignment to ensure that it is centered within the brake pads.

Step 5: Re-Bed In the Brake Pads

If your brake pads are new or have been replaced, it’s important to perform a proper bedding-in procedure. Bedding-in ensures that the pads transfer a layer of material to the rotor for optimal braking performance and noise reduction.

Instructions:

1. To bed in your new brake pads, take your bike to a quiet, safe location where you can perform the procedure without distractions.
2. Begin riding at a moderate speed (around 15-20 mph) and apply the brakes gently to bring the bike to a stop. Do this several times in succession, allowing the brakes to cool slightly between each stop.
3. After about 5-10 braking cycles, increase the braking force slightly, but avoid a sudden, harsh stop.
4. Repeat this process until the brakes feel solid and the noise has reduced significantly.

Final Checks and Maintenance Tips

After completing the steps above, it’s important to conduct a final check to ensure that everything is functioning as expected.

• Test your brakes: After reassembling the wheel and making adjustments, test the brakes by riding at a slow speed and gradually applying the brakes. Listen for any remaining noise.
• Keep the system clean: Regularly clean the brake pads and rotors to prevent noise caused by dirt or oil buildup.
• Replace worn components: If your brake pads or rotors are excessively worn, replace them promptly to maintain safe braking performance.

By following these steps, you should be able to resolve most common issues related to noisy or squealing Shimano BR-R7170 disc brakes. Regular maintenance and proper setup will keep your bike’s braking system running smoothly and quietly, allowing you to ride with confidence and safety.