The Shimano BR-6700 [paid link] caliper brakes are part of the Ultegra 6700 series, well-known for their performance, reliability, and aerodynamic profile. Designed for road cyclists who demand efficient stopping power and modulation, the BR-6700 [paid link] brakes deliver solid performance when properly set up. However, like any precision component, they can exhibit issues due to misalignment, cable tension errors, wear, or improper maintenance. This guide walks through the most frequent braking problems associated with the BR-6700 [paid link] and offers clear, actionable fixes.
Brake Lever Pulls Too Close to the Handlebar
One of the most common complaints with the BR-6700 is a mushy lever feel or levers that pull too far before engaging the brakes. This typically stems from insufficient cable tension or improper pad clearance.
Solution:
Start by checking cable tension at the barrel adjuster. Turn the adjuster counterclockwise to increase tension. Ensure the brake pads are positioned close enough to the rim without rubbing. If tension at the barrel isn’t enough, you may need to reset the cable at the pinch bolt. Loosen the bolt, pull more cable through, and retighten firmly. Check pad centering again after adjustment.
Brake Calipers Not Centered Over the Rim
An off-center brake caliper will cause uneven braking and rim rub on one side. On the BR-6700, this can happen from either cable pull bias or spring tension imbalance.
Solution:
Use the centering screw located on the side of the brake arm. Turn clockwise or counterclockwise in small increments while applying the brake lever to test alignment. The goal is to achieve equal pad clearance on both sides. If the caliper consistently returns to an off-center position, inspect the mounting bolt for proper torque and ensure the washer stack behind the brake bridge is correctly assembled.
Brakes Feel Weak or Lack Power
If the brakes feel underwhelming or unresponsive, contamination or poor pad condition may be the root cause. The BR-6700 uses standard Shimano-compatible pads that can wear down or glaze over.
Solution:
Inspect the brake pads for embedded debris or glazing. Clean with fine sandpaper if lightly glazed, or replace if worn. Rims should also be cleaned with isopropyl alcohol to remove any residue or brake dust. Check for oil contamination from recent drivetrain lubrication—this can drastically reduce braking efficiency. Always degrease thoroughly if contamination is suspected.
Squealing or Noisy Braking
High-pitched squeals during braking on the BR-6700 are often linked to improper toe-in or pad alignment. A slight angle where the leading edge of the pad contacts the rim first can eliminate vibration-induced noise.
Solution:
Realign the brake pads by loosening the pad fixing bolt and adjusting so that the front edge contacts the rim slightly before the rear. Use a thin business card between the rear of the pad and the rim during tightening to achieve proper toe-in. Avoid overtightening to prevent angle shift.
Brake Pads Drag on One Side
A common frustration with the BR-6700 setup is when one pad continues to contact the rim after release. This usually relates to spring tension imbalance or cable misrouting.
Solution:
Ensure the caliper arms move freely by applying a small amount of bike-specific grease to the pivot points. Next, adjust spring tension by fine-tuning the centering screw. If the problem persists, reset the cable and recheck pad alignment. Avoid overtightening the mounting bolt, as this can restrict arm movement.
Brakes Don’t Fully Release After Braking
Sticking or slow return of the BR-6700 arms can indicate corrosion or internal binding. Poor cable routing or friction inside the housing may also hinder return motion.
Solution:
Inspect and lubricate the brake pivot points with a light PTFE-based lubricant. If the cable housing is old or has sharp bends, consider replacing it. Always use stainless steel cables and lubricated housing liners for optimal performance. Verify that the return spring is engaging correctly by observing the caliper’s movement without cable tension.
Lever Pulls But Nothing Happens
If the brake lever moves freely but the brake doesn’t engage, this suggests a detached or broken cable inside the housing or at the pinch bolt.
Solution:
Stop riding immediately and inspect the brake cable. At the lever end, pull the hood back and inspect the anchor. At the caliper, check the pinch bolt to ensure the cable hasn’t slipped out or frayed. If the cable is damaged, replace it with a new stainless steel inner cable and ensure proper clamping and tension.
Creaking or Flex During Braking
Unusual creaking or flexing sensations may stem from improper mounting or frame interface problems.
Solution:
Check that the caliper mounting bolt is torqued to Shimano’s recommended spec (6–8 Nm). Remove the brake and clean the brake bridge surface, then reassemble with appropriate torque. For carbon frames, always use the correct brake washers and do not overtighten.
Conclusion
Troubleshooting BR-6700 brakes requires methodical inspection and precise adjustments. Most common issues—whether it’s weak braking, pad rub, noise, or poor return—can be resolved with basic tools and attention to setup detail. Always ensure cleanliness, proper cable routing, and pad positioning. Periodic inspection helps maintain consistent performance and extends component lifespan.
Frequently Asked Questions
1. How do I know if my BR-6700 brake pads need replacing?
Check the grooves on the pad surface. If they’re worn down or the pad has reached the wear line, it’s time to replace them.
2. What tools do I need to adjust the centering screw on BR-6700 brakes?
A small Phillips or flathead screwdriver will work for the centering screw adjustment on the caliper arm.
3. Can I use carbon-specific brake pads with the BR-6700?
Yes, but only when using carbon rims. Always match the pad compound to the rim type to avoid poor performance or rim damage.
4. Why are my BR-6700 brakes still squealing after toe-in adjustment?
Try cleaning the rims thoroughly, sanding the pad surface lightly, and verifying that the brake surface is not glazed or damaged.
5. Do I need to lubricate my BR-6700 brakes?
Yes, apply a light lubricant to the pivot points periodically. Avoid getting lube on the pads or rim.
6. Can I mix BR-6700 brakes with newer 11-speed Shimano STI levers?
Yes, the BR-6700 calipers are compatible with Shimano STI levers designed for road calipers, though newer models may offer slightly improved leverage ratios.