The Shimano SM-BB5700 [paid link] bottom bracket is part of the company’s 105 5700 series and is a threaded external bearing bottom bracket designed for Hollowtech II road cranksets. Although it is a dependable and widely-used model, improper installation and setup can lead to performance issues that affect the entire drivetrain. If your bike is making creaking noises, the crank arms feel unstable, or you’re experiencing inconsistent shifting, the problem could be rooted in how the SM-BB5700 [paid link] was installed or adjusted.
This article provides a detailed breakdown of common SM-BB5700 [paid link] setup issues, how to correctly diagnose and fix them, and what to do to ensure optimal performance and longevity of the component.
Tools Required
- 5mm and 8mm Allen keys [paid link]
- Hollowtech II bottom bracket tool [paid link] (e.g., TL-FC32 [paid link])
- Torque wrench [paid link] (recommended range: 35–50 Nm for crank arm bolts)
- Anti-seize compound or grease
- Thread preparation compound (if needed)
- Clean rag or paper towels
Improper Frame Preparation: A Hidden Culprit
The SM-BB5700 requires a BSA-threaded (1.37″ x 24 TPI) bottom bracket shell with an English thread pattern. If the bottom bracket shell isn’t properly cleaned and faced before installation, it can cause misalignment between the bearing cups, leading to poor crank performance.
Symptoms of poor frame prep include:
- Uneven bearing wear
- Creaking noises under load
- Difficult crank installation
To avoid these issues, ensure that both faces of the bottom bracket shell are parallel and clean. Use a facing tool if necessary, especially on older or repainted frames. Dirt or paint residue can prevent the cups from seating flush, resulting in bearing stress and eventual failure.
Incorrect Torque Values on Bearing Cups
Over-torquing or under-torquing the bearing cups can cause damage to the threads or allow the cups to move during riding. Shimano recommends a torque specification of 35–50 Nm when installing the cups.
If the torque is too low, the cup may loosen, leading to creaks and misalignment. On the other hand, excessive torque can damage the threads in the frame or the cups themselves.
To avoid this, always use a torque wrench [paid link] when tightening the bearing cups and apply an anti-seize compound to prevent thread galling, especially in metal frames.
Lack of Grease or Incorrect Use of Threadlocker
The interface between the frame and the bottom bracket threads should either be greased (for steel and aluminum frames) or treated with a suitable threadlocker (for carbon frames or creak-prone setups).
Without lubrication or appropriate bonding agents, micro-movements occur under load, causing persistent noises and loosening.
Fix:
- For aluminum/steel frames: Apply a generous layer of anti-seize or waterproof grease on the threads.
- For carbon frames: Use a medium-strength threadlocker that’s carbon-safe and allows future service.
Incorrect Installation of Crankset
Even when the bottom bracket itself is correctly installed, errors in crank arm installation can cause problems. The Hollowtech II crank arms must be preloaded correctly and tightened to spec.
Common errors include:
- Skipping the crank arm preload cap
- Uneven tightening of pinch bolts
- Reusing deformed fixing bolts
Ensure that the preload cap is snug (not overtightened) before securing the pinch bolts alternately and evenly. Use a torque wrench [paid link] and follow Shimano’s specified tightening order to avoid introducing lateral stress on the bearings.
Poor Bearing Condition or Factory Defects
Although rare, defective or prematurely worn bearings can compromise the setup. The SM-BB5700 uses steel bearings that can degrade over time due to water ingress or poor lubrication.
Indicators include:
- Gritty feel when rotating crankset
- Resistance or noise even after proper installation
- Bearing play or visible rust near seals
If your setup seems correct but the crank still feels off, consider replacing the bottom bracket entirely, especially if you’ve logged more than 5,000–8,000 kilometers on it.
Incompatible Frame or Crankset Interface
Despite being a BSA-threaded unit, the SM-BB5700 is only compatible with Hollowtech II cranks. Attempting to install a different type of crankset (such as a GXP [paid link] or BB30 conversion crank) without proper adapters will inevitably lead to setup problems.
Check your crank’s spindle diameter and spacing. The SM-BB5700 supports a 24mm spindle, and the bearing width is calibrated for Shimano’s standard spindle spacing. Using a mismatched system can cause poor bearing alignment, premature wear, and functional inefficiency.
Environmental Contamination and Improper Sealing
Another often overlooked issue is contamination by dirt, water, or cleaning agents. If the seals on the SM-BB5700 are compromised during installation or cleaning, it leads to internal rusting and drag.
Avoid high-pressure water directly on the bottom bracket area and routinely inspect the seals for any signs of damage. Applying a light waterproof grease around the external seals can offer an extra layer of protection.
Final Checks Before Riding
Once installed, rotate the crank by hand and feel for smoothness and silence. Listen for creaks under load, check that crank arms spin freely without resistance, and ensure there is no lateral play.
Re-torque the crank arm bolts after your first short ride to ensure nothing has settled or shifted.
Conclusion
Improper setup of the Shimano SM-BB5700 can lead to a range of avoidable performance issues. By understanding how each part of the installation process impacts functionality—from frame prep and torque accuracy to crank compatibility—you can eliminate the guesswork and ensure a noise-free, efficient ride.
Take time to inspect each installation step methodically. When done correctly, the SM-BB5700 offers durable, smooth operation and reliability even under demanding road conditions.