Troubleshooting SM-BB5700: How to Fix Common Set-Up Issues

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The Shimano SM-BB5700 [paid link] is a Hollowtech II bottom bracket designed for road bikes using a BSA (British Standard Thread) bottom bracket shell. Known for its durability and smooth spinning performance, the SM-BB5700 [paid link] is a favorite among Shimano 105 series users. However, like any threaded bottom bracket, improper installation or maintenance can lead to a range of performance issues. This guide will walk you through the most common SM-BB5700 [paid link] set-up problems and how to fix them for optimal performance.

Understanding the SM-BB5700 Bottom Bracket

The SM-BB5700 is engineered for 68mm or 70mm BSA threaded bottom bracket shells and pairs with Shimano’s Hollowtech II cranksets. Its two external bearing cups house the precision bearings and are pre-greased for optimal longevity. Proper installation requires careful attention to shell preparation, torque specifications, and spacer placement.

Common Set-Up Problems with the SM-BB5700

1. Creaking or Clicking Noises During Pedaling

Creaks are a common issue with external bottom brackets and are often mistaken for frame or crank problems. For the SM-BB5700, creaking can stem from improper torque, dry threads, or contamination between mating surfaces.

Key Fixes:

  • Remove the crankset and bottom bracket.
  • Clean all threads and surfaces thoroughly.
  • Apply anti-seize compound on the shell threads and re-torque the cups to Shimano’s recommended specification (35–50 Nm).
  • Ensure no contamination or grit is trapped between crank arm interfaces or bearing faces.

2. Misalignment of Bearings Leading to Drag

If the shell faces are not properly aligned or faced post-manufacturing, the bearing cups may seat unevenly. This can cause resistance in crank rotation or premature bearing wear.

Key Fixes:

  • Check shell alignment using a bottom bracket facing tool.
  • If misalignment is present, face the bottom bracket shell to create parallel, smooth surfaces.
  • Reinstall the bottom bracket ensuring symmetric torque is applied to both cups.

3. Loose Crankarms After Installation

If the left crankarm comes loose, the preload cap or pinch bolts may not have been installed correctly.

Key Fixes:

  • Remove the crankarm and inspect for wear or deformation.
  • Reinstall using the Shimano preload cap tool (TL-FC16 [paid link]) to set the bearing preload without overtightening.
  • Tighten the pinch bolts alternately and incrementally to 12–14 Nm to prevent uneven stress.

Troubleshooting Bottom Bracket Fit Issues

1. Incorrect Use of Spacers

Improper or missing spacers can lead to bearing misalignment, poor crank fitment, or rubbing.

Key Fixes:

  • For 68mm shells, no spacers are needed for double chainring setups.
  • For 70mm shells, a 2.5mm spacer may be necessary depending on crankset compatibility.
  • Refer to the Shimano compatibility chart to confirm the spacer configuration.

2. Cross-Threading During Installation

Damaged threads can result from improper threading of the cups, especially when starting without aligning the threads carefully.

Key Fixes:

  • Always thread cups by hand initially before applying torque.
  • If resistance is felt early, stop and inspect threading.
  • Use a thread chaser if the shell threads are damaged.

Addressing Bearing Wear and Contamination

1. Water or Dirt Intrusion

Though the SM-BB5700 is sealed, frequent riding in wet conditions can force contaminants past the seals.

Key Fixes:

  • Periodically remove the crankset and inspect the bearings.
  • If roughness is detected, bearings may need to be replaced or the entire unit swapped.
  • Apply waterproof grease around the bearing cups and frame interface before installation.

2. Excessive Bearing Drag or Stiffness

Stiff crank movement can indicate over-tight preload or worn-out bearings.

Key Fixes:

  • Reset the preload using the cap and avoid overtightening.
  • If resistance persists, replace the SM-BB5700 with a new unit.
  • Ensure the crank spindle is not damaged or pitted.

Preventing Future Set-Up Issues

Routine maintenance and attention to detail during installation can prevent most SM-BB5700 problems. Use the correct tools, follow torque specs, and always prep surfaces before assembly.

  • Inspect the bottom bracket every 1,000–2,000 km, especially if ridden in poor weather.
  • Keep torque values consistent: drive-side cup (right) is right-hand threaded; non-drive-side (left) is left-hand threaded.
  • Avoid mixing components from incompatible series or generations.

FAQs about SM-BB5700 Troubleshooting

1. How can I tell if my SM-BB5700 bearings are worn out?
You’ll feel roughness or grinding when spinning the crank by hand. Visual signs of corrosion or leaking grease are also indicators.

2. Why does my crankset feel tight after installation?
It could be due to over-tightened preload caps or misaligned bearing cups. Always check preload settings and reface the shell if necessary.

3. Can I service the bearings in the SM-BB5700?
Technically no. The SM-BB5700 is a sealed unit, and Shimano recommends replacement when bearings degrade.

4. What grease should I use when installing the SM-BB5700?
A waterproof anti-seize compound or high-quality bearing grease is ideal for threaded interfaces and preventing creaks.

5. My crank arms keep coming loose. Is the bottom bracket to blame?
Usually not. It’s more likely an issue with crank bolt torque or poor pinch bolt tightening technique.

6. Do I need a special tool to install or remove the SM-BB5700?
Yes, you’ll need a Hollowtech II compatible bottom bracket tool [paid link], such as Shimano TL-FC32 [paid link] or Park Tool BBT-9.

Conclusion

The Shimano SM-BB5700 is a reliable and smooth-performing bottom bracket when properly installed and maintained. By addressing common set-up issues—such as creaking, misalignment, and preload errors—you can ensure longevity and consistent performance. Attention to detail, correct tool use, and regular inspection are key to keeping your SM-BB5700 functioning like new.