How To Adjust Mountain Bike Brakes?

Having properly adjusted brakes is crucial for a safe and effective riding experience. Mountain biking places intense demands on brake systems, and incorrectly adjusted brakes can lead to poor stopping power, loss of control, and potentially dangerous situations. 

By learning How To Adjust Mountain Bike Brakes? you can optimize the performance to match your riding style and terrain.

Types of Brakes on Mountain Bikes

There are two main types of brake systems on modern mountain bikes – rim brakes and disc brakes.

Rim Brakes

Rim brakes clamp brake pads onto the rim of the wheels to slow momentum through friction. They have been the traditional option on bikes for decades.

Pros:

• Lightweight and mechanically simple
• Easier to inspect pad wear
• Often less expensive to maintain

Cons:

• Less stopping power, especially in wet/muddy conditions
• Pads wear rims overtime
• Small clearance for wide tires

Disc Brakes

Disc brakes use calipers to squeeze brake pads against a rotor attached to the hub of the wheel. The increased braking surface provides superior stopping power.

Pros:

• Much stronger braking, even in poor conditions
• Does not wear out rims
• Compatible with wider tires

Cons:

• Heavier
• More complicated to maintain
• Pads and rotors wear out

Tools Needed for Adjustment

Before getting started with adjustments, make sure you have the necessary tools:

• Bike stand or method to safely secure the bike
• Set of metric Allen wrenches
• Adjustable wrench
• Torque wrench
• Brake cable cutters
• Replacement brake pads

Quality tools help ensure adjustments go smoothly and safely. Always consult your owner’s manual for the proper tools and torque specs.

Step-by-Step Guide to Adjusting Brakes

The specific steps involved in tuning your brakes vary slightly depending on the exact model and type. But the general process is similar for all systems:

1. Inspect the Brakes

First, inspect the condition of the entire brake system:

• Check brake pads – are they worn down or contaminated? Replace if necessary.
• Examine brake cable housing – any rust or fraying?
• Look for fluid leaks (in hydraulic systems).
•  Assess rotor/rim condition– excess wear, warping?

Addressing any issues here first allows adjustments to be made to a system in good working order.

2. Center the Brake Caliper

The caliper needs to be aligned over the exact center of the rotor/rim for even pad contact.

For rim brakes:

• Loosen the brake cable to allow the arms to center.
• Adjust the centering screw until aligned.

For disc brakes:

• Loosen caliper mounting bolts.
• Pull the brake lever to center the caliper over the rotor.
• Alternately tighten bolts to secure them.

3. Adjust Pad Spacing

The inward and outward pad adjustment dials fine-tune the spacing of the pads from the braking surface.

• Start with both pads adjusted outward, away from the rotor/rim.
• Turn inward equally until there is even contact across the entire braking surface when the lever is pulled.
• Double-check alignment if one pad contacts before the other.

4. Adjust Cable Tension

Proper cable tension ensures the pads engage firmly without dragging or requiring excessive lever force.

• For rim brakes – loosen the cable fixation bolt and pull the cable taut. Tighten the bolt while maintaining tension.
• For hydraulic disc brakes, – dial the barrel adjuster to add slight tension until the brakes engage without dragging.

5. Secure Fasteners

• Tighten any loose fasteners to specified torque specs.
• Avoid over-tightening.

6. Test Braking Performance

• Check for proper lever engagement point and pad clearance.
• Confirm pads wear evenly with full braking force distributed across the braking surface.
• Make small further adjustments as needed.

7. Bed in New Pads and Rotors

When installing new pads and rotors, follow the bedding-in process:

• Accelerate the bike to moderate speed.
• Firmly apply brakes to gently slow to a near stop.
• Repeat approximately 20 times to properly mate surfaces.

This helps establish optimal friction between the surfaces right away.

See also: 
How To Bleed Mountain Bike Brakes? 

How To Remove Sand From Your Bike [Bike Maintenance]

Best Practices

Follow these tips for the best brake function after adjustments:

• Keep rotors and rims clean of oils, greases, and debris that hinder braking.
• To reduce squealing, use brake-specific cleaners and lubricants like isopropyl alcohol or disc brake quiets.
• Check pad thickness periodically and replace once worn down to the minimum safe level.
• Immediately address any loss of braking power, fade, or leakage issues.
• Store the bike out of the weather and direct sunlight when not riding.
• Consider professional brake service at least annually.

Properly maintained brakes greatly enhance control and safety. Take the time to regularly adjust them to suit your riding.

Troubleshooting Common Brake Problems

If your brakes still are not performing well after adjustment, here are some common issues to check:

Brakes screeching/squealing:

• Clean rotors, rims, and pads of contaminants.
• Replace worn pads.
• Lubricate contact points with appropriate brake lubricant.

Pads dragging on rotor/rim:

• Check for proper caliper alignment.
• Adjust cable tension or hydraulic pistons inward to increase spacing.

Brakes feel spongy/weak:

• Ensure tight cable connections with proper housing.
• Refill hydraulic fluid if low. Bleed the system if air bubbles are present.
• Replace worn pads and rotors.

Uneven braking/juddering:

• Realign the caliper if necessary.
• Check for warped rotors – resurface or replace.

Brake fade during prolonged braking:

• Allow the system to cool fully between brake sessions.
• Upgrade to higher quality pads and rotors better suited for the conditions.

Leaking brake fluid:

• Examine hydraulic fittings and seals for damage allowing fluid to escape. Replace as needed.

Still, having issues? Consult a professional bike mechanic for further troubleshooting and repairs.

Frequently Asked Questions

Should I choose rim or disc brakes for my mountain bike?

For most mountain bike riding, disc brakes provide stronger, more consistent all-weather stopping power. But rim brakes can still work well on less extreme terrain. Consider your specific riding style and conditions.

How often should brake pads be replaced?

As pads wear down, replace them once they reach the minimum thickness recommended by the manufacturer, usually around 2mm or less. This helps ensure adequate friction material for safe braking.

What maintenance is required for disc brakes?

Disc systems require periodically retightening fasteners, replacing worn pads, cleaning rotors, and inspecting for leaks. Bleeding hydraulic lines to remove air as needed also helps maintain optimal performance.

Should I upgrade my brakes if I plan on riding steeper terrain?

For downhill riding or steep slopes, increased stopping power can help maintain proper control. For the most demanding terrain, consider upgrading to larger rotors, metal brake pads, and multi-piston calipers.

How do I know if my rotors are warped?

Warped rotors produce excessive vibration and uneven braking. Visually check rotors for a wavy appearance while slowly spinning the wheel. Resurfacing or replacing rotors usually fixes this issue.

Conclusion

Properly adjusted brakes are one of the most important safety components on any mountain bike. 

While the process may seem complicated at first, learning how to fine-tune rim brakes or disc brakes to match your riding will give you confidence and control. 

Start by keeping the system clean and lubricated, then methodically work through centering, pad adjustment, tension, and testing steps. Reference your owner’s manual or consult a bike shop if needed. 

Taking the time to optimize your brakes will give you a better cycling experience on a mountain bike.