Bicycle Hydraulic Disc Brake Pad Bedding-In Tutorial: The Correct Way to Break In New Brake Pads

Introduction: Why Are New Brake Pads So Weak?

You’ve just replaced your brake pads, head out for a ride full of excitement, squeeze the brake lever—“Why is there barely any power?” Squeeze harder—“Still feels mushy!” Then, on a descent, the brakes start emitting a sharp squeal, as if someone is blowing a whistle right into your ear.

Congratulations, you’ve encountered a problem every disc brake cyclist faces: new brake pads that haven’t been bedded in (Bedding-in / Break-in).

What is Brake Pad Bedding-In?

Brake pad bedding-in is the process of evenly transferring a thin layer of friction material from the brake pads onto the surface of the disc rotor. This layer of material can:

1. Increase braking power: Significantly improves the friction coefficient
2. Eliminate noise: Reduces squealing and abnormal sounds
3. Ensure even wear: Allows the pad surface and rotor to achieve full contact
4. Stabilize brake feel: Makes braking force consistent with every pull

Types and Characteristics of Brake Pads

Organic Brake Pads (Resin / Organic)

Characteristic	Description
Material	Organic fibers + resin binder
Braking Power	Moderate
Noise	Quieter
Wear Rate	Faster
Suitable Environment	Dry weather, recreational riding
Bedding-In Difficulty	★★

Metallic Brake Pads (Metallic / Sintered)

Characteristic	Description
Material	Metal powder + high-pressure sintering
Braking Power	Strong
Noise	Louder
Wear Rate	Slower
Suitable Environment	Rainy days, mountain roads, heavy use
Bedding-In Difficulty	★★★★

Semi-metallic Brake Pads

Falls between organic and metallic, combining characteristics of both.

Advice for Taiwanese Cyclists: Taiwan is rainy and mountainous, so metallic brake pads offer better durability and wet-weather performance. However, the bedding-in process for metallic pads also requires more patience.

Preparation Before Bedding-In

Confirm Correct Installation

Before bedding-in, first check the condition of the brake pads and rotor:

1. Pad Direction: Install according to any directional markings
2. Rotor Cleaning: Wipe the rotor with a dedicated disc brake cleaner or alcohol
3. Clean Pads: Must be free of oil contamination (finger oil counts too!)
4. Caliper Alignment: The rotor should be exactly centered between the pads, not leaning to one side
5. Correct Wheel Installation: Quick release or thru-axle securely tightened

Important Taboos

• Never touch the friction surface of the pads with your fingers: Skin oils will contaminate the pads
• Never touch the rotor with your fingers: Same as above
• Do not use WD-40 or any oil-containing cleaners: The pads will be permanently ruined
• Do not brake continuously for long periods without bedding-in: This can cause “glazing”

Bedding-In Procedure: Standard Process

Find a Safe Location

• A flat road or gentle downhill slope
• Low traffic and few pedestrians
• Dry road surface
• At least 100-200 meters of straight-line space

Front Brake Bedding-In

1. Accelerate to about 25-30 km/h
2. Apply the front brake smoothly and firmly, reducing speed to about 5-8 km/h
3. Release the brake completely
4. Accelerate again to 25-30 km/h
5. Repeat the above steps 15-20 times

Rear Brake Bedding-In

Follow the same steps, but using the rear brake.

Key Points

• Do not come to a complete stop: The heat from braking at a full stop can leave an imprint on the rotor
• Progressive force: Pull lightly for the first few times, gradually increasing force later
• Allow the rotor to cool: After every 5 braking cycles, ride for a stretch to let the rotor cool down
• Do each side separately: Bed in the front and rear brakes independently

Bedding-In Procedure: Advanced Process (Metallic Pads)

Metallic brake pads require a more thorough bedding-in process:

Phase 1: Light Bedding-In (10 times)

• Speed: 20 km/h
• Braking Force: 30% effort
• Purpose: Initial material transfer

Phase 2: Medium Bedding-In (10 times)

• Speed: 25 km/h
• Braking Force: 50% effort
• Purpose: Establish a uniform friction layer

Phase 3: Heavy Bedding-In (10 times)

• Speed: 30 km/h
• Braking Force: 70-80% effort
• Purpose: Harden the friction layer

Phase 4: Cooling Down

• Ride for 5-10 minutes without braking
• Allow the rotor and pads to cool down completely

Determining if Bedding-In is Complete

How do you know if bedding-in was successful?

Indicator	Not Bedded-In	Bedding-In Complete
Braking Power	Weak and feeble	Consistent and strong
Brake Noise	Squealing or grinding	Quiet or a slight hiss
Lever Feel	Inconsistent	Linear and stable
Rotor Appearance	Shiny or uneven	Uniform gray film
Pad Surface	Smooth	Slightly glossy, flat surface

Common Problems and Solutions

Still Noisy After Bedding-In

Possible causes and solutions:

1. Caliper Misalignment: Re-align the caliper position
2. Bent Rotor: Straighten using a rotor truing tool
3. Contaminated Pads: If contaminated with oil, replacement is necessary
4. Dirty Rotor: Clean thoroughly with isopropyl alcohol

Glazed Brake Pads

If bedding-in is done improperly, a smooth, shiny “glass” layer can form on the pad surface:

Symptoms: Very weak braking power, surface looks shiny

Solution:

1. Gently sand off the glazed layer using 200-grit sandpaper
2. Clean the pads and rotor with alcohol
3. Repeat the bedding-in procedure

Brake Fluid Contaminated the Pads

This is the most painful experience for disc brake cyclists:

Symptoms: Brakes are completely powerless and cannot be improved through bedding-in

Solution:

• Minor Contamination: Oven method—bake the pads in an oven at 200°C for 15 minutes (will produce an odor, recommended to do outdoors)
• Severe Contamination: Replace with new brake pads directly
• Rotor: Clean thoroughly with isopropyl alcohol or disc brake cleaner

Special Notes for Taiwanese Disc Brake Cyclists

Bedding-In on Rainy Days?

• Try to bed-in during dry weather
• Bedding-in is less effective in the rain and can easily cause uneven transfer
• If you can only ride on rainy days, increase the number of bedding-in cycles by 50%

Advice Before Descending Wuling

• Confirm the brake pads are fully bedded-in before a long descent
• Carry a spare set of brake pads
• Metallic pads perform significantly better than organic ones on long descents
• Alternate using front and rear brakes to avoid overheating one side

Brake Pad Replacement Frequency

Riding Type	Organic Pads	Metallic Pads
Mostly Flat Roads	3000-5000km	5000-8000km
Mostly Mountain Roads	1500-3000km	3000-5000km
Frequent Rain Riding	1000-2000km	2000-4000km

Conclusion

Brake pad bedding-in is a simple but crucial procedure. Spend 15-20 minutes doing it properly, and your disc brakes will provide stable, quiet, and powerful stopping performance. Hit the road without bedding-in, and what awaits you are squealing noises and weak braking power.

Every time you install new brake pads, remember to complete the bedding-in process in a safe place before heading out for a ride. Your braking system and your riding buddies’ ears will thank you.

Related Reading

• Disc Brake Pad Material Comparison: Resin vs. Metallic Sintered vs. Semi-Metallic
• Brake Pad Alignment and Bedding-In: The Key to Optimal Braking Performance
• Bicycle Brake Disc Maintenance: Truing, Cleaning, and When to Replace
• Disc Brake vs. C-Clamp Brake Adjustment: A Complete Maintenance Guide for Both Brake Systems