Gravel riders often face terrain that demands both resilience and reliability from their braking systems. The Clarks CMD‑22C Mechanical disc brake set has carved a niche for itself among cyclists looking for consistent braking performance without the complications of hydraulic systems. This expert guide delves into why the CMD‑22C Mechanical brake set is a top choice for gravel bikes, offering a detailed breakdown of installation, adjustment, troubleshooting, and performance optimization.
Tools Required
- 5mm Allen wrench
- 2.5mm Allen wrench
- Torque wrench (with Nm scale)
- Disc rotor truing tool
- Isopropyl alcohol & clean rags
- Mechanical brake cable and housing cutter
- Cable end crimper
- Rotor lockring tool (for centerlock rotors)
Installation Guide for CMD‑22C Mechanical Brake Set
Installing the CMD‑22C requires precision to ensure optimal performance. Begin by mounting the caliper to the frame or fork post mount using the provided bolts. These bolts should be torqued to the manufacturer’s recommended setting of 6–8 Nm to prevent loosening under vibration.
Next, install the mechanical brake cable. Route the inner cable through a compatible housing with minimal bends, terminating it at the caliper’s actuation arm. Secure the cable with a 5mm Allen key, ensuring adequate tension without preloading the caliper.
Once connected, install the disc rotor to the hub using the appropriate standard (6-bolt or centerlock). Use a torque wrench to tighten rotor bolts to 6 Nm. Always clean rotors with isopropyl alcohol before use to remove factory residue.
Proper Adjustment for Optimal Braking Power
To ensure efficient braking, start by centering the caliper. Loosen the caliper mounting bolts slightly and squeeze the brake lever. While holding the lever, tighten the bolts evenly. This aligns the caliper with the rotor.
Pad-to-rotor spacing is managed using the dual inboard and outboard pad adjustment screws. Turn these with a 2.5mm Allen key to fine-tune each pad’s position. Set pads to sit approximately 0.2 mm from the rotor for immediate engagement without rubbing.
Cable tension is crucial. Adjust the barrel adjuster on the brake lever or inline adjuster near the caliper to fine-tune lever feel and engagement point. A firm yet progressive lever feel indicates correct setup.
Routine Maintenance for Consistent Performance
Maintenance of mechanical brakes like the CMD‑22C is relatively straightforward. Begin by inspecting the brake pads for wear; replace them when the pad material drops below 1 mm. Clarks recommends checking every 500 km under average riding conditions.
Clean rotors with alcohol and a lint-free cloth after muddy or wet rides to prevent pad contamination. Cable stretch is natural in the first few rides; retighten the cable clamp bolt after initial bedding.
Lubricate the cable housing with a PTFE-based lube periodically to reduce friction and improve lever feel. Avoid over-lubing as residue can attract grit [paid link], particularly on gravel rides.
Troubleshooting Common CMD‑22C Setup Issues
If the brake feels spongy, it often indicates cable slack or misalignment of the caliper. Recheck the cable tension and recenter the caliper as described. For persistent rotor rub, inspect rotor trueness using a truing tool and adjust with slight, controlled bends.
A noisy brake is usually due to contamination. Thoroughly clean the rotor and replace pads if oil has soaked into them. Squealing under load may also be reduced by lightly sanding the pads and rotor to refresh the surface.
If one pad wears faster than the other, inspect the actuation arm. It should move freely and return to rest when released. Lubricate the pivot points if resistance is felt.
Customization and Optimization for Gravel Use
Gravel riders often seek precise modulation and lightweight setups. The CMD‑22C offers outboard pad adjustment, allowing for a tighter lever feel preferred on uneven terrain. By using compressionless housing, cable friction can be reduced, yielding smoother engagement.
Brake pad upgrades are available, including sintered metallic compounds for extended life in wet conditions. Additionally, pairing with larger 160mm rotors (if frame clearance allows) enhances stopping power on descents.
For riders seeking enhanced control, ergonomic levers with a longer pull ratio can improve modulation without upgrading to hydraulics.
Compatibility with Other Drivetrain Components
The CMD‑22C caliper is compatible with standard mechanical road levers, including Shimano STI, SRAM DoubleTap, and MicroSHIFT levers. It uses a short-pull actuation ratio, making it unsuitable for linear-pull or V-brake levers.
When integrating into a 1x or 2x drivetrain, the CMD‑22C does not interfere with shifting systems. It is agnostic to derailleur brands, so long as mechanical road levers are used.
For riders mixing brands across the drivetrain, CMD‑22C’s mechanical simplicity offers seamless integration without requiring brand-specific levers or rotors.
CMD‑22C Mechanical vs. Similar Brake Sets
Compared to the TRP Spyre, the CMD‑22C offers similar dual pad movement but at a more accessible price point. While TRP may feature slightly more refined construction, the CMD‑22C delivers strong, reliable performance ideal for gravel adventures.
In contrast to the Avid BB7, the CMD‑22C’s design allows for quicker centering and more straightforward setup. It lacks the aggressive modulation of the BB7 but compensates with a quieter, smoother braking curve.
While Tektro Lyra is another entry-level option, it often struggles under heavy loads. The CMD‑22C holds an advantage in durability and pad longevity, particularly in abrasive environments like gravel trails.
Frequently Asked Questions
1. Can I use CMD‑22C brakes with flat bar levers?
No. These calipers require short-pull road levers and are not compatible with flat bar levers unless a travel adapter is used.
2. How often should I replace the brake pads?
Replace pads when the thickness falls below 1 mm. For gravel use, inspect every 500–700 km depending on terrain.
3. Are CMD‑22C calipers compatible with hydraulic road levers?
No. Hydraulic levers are designed for hydraulic calipers. The CMD‑22C is strictly for mechanical lever systems.
4. What’s the ideal rotor size for gravel riding with CMD‑22C?
160mm rotors are ideal for most gravel applications, offering a balance of power and control.
5. Why do my brakes squeal after installation?
Brake squeal usually indicates contamination or improper bedding. Clean rotors and perform a bedding-in process with several firm stops.
6. Can I install these calipers on post-mount and flat-mount frames?
Yes, but you’ll need the correct adapter for flat-mount installations. Post-mount bolts are included in the package.
Conclusion
The Clarks CMD‑22C Mechanical brake set delivers reliable stopping power, straightforward maintenance, and compatibility with most mechanical road setups. Its performance and simplicity make it a dependable choice for gravel riders seeking control and resilience in demanding conditions. Whether you’re upgrading from older calipers or building a new gravel bike, the CMD‑22C stands out as a trustworthy braking solution.