Troubleshooting Shimano FC-5700 Crankset: How to Fix Common Power Transfer Issues

Posted on
in No category

The Shimano FC-5700 [paid link] crankset, part of the 105 series, is a solid and reliable component for both beginners and seasoned cyclists. While the FC-5700 [paid link] crankset is designed for efficient power transfer, several common issues can impact its performance. These issues can often be traced to incorrect installation, lack of maintenance, or improper adjustments. In this guide, we will go over the most frequent power transfer issues and how to troubleshoot and resolve them, ensuring your Shimano FC-5700 [paid link] crankset performs at its peak.

1. Lack of Smooth Pedaling: Poor Power Transfer

One of the most noticeable issues cyclists face with the Shimano FC-5700 crankset is a lack of smooth pedaling, which leads to inefficient power transfer. The issue might feel like a lag or stuttering when pedaling, which can significantly affect performance, especially during climbs or sprints.

Possible Causes:

  • Loose crank arms: If the crank arms are not properly tightened, they can cause a wobbling effect that interferes with smooth pedaling.
  • Worn out bearings: Over time, the bearings inside the bottom bracket may wear down, causing resistance and uneven pedaling.
  • Incorrect Q-factor: The Q-factor, or the distance between the pedals, can affect the efficiency of power transfer. If the crankset is misaligned or not properly installed, it can lead to improper power transfer.

How to Fix:

  • Tighten the crank arm bolts: Use a torque wrench [paid link] to ensure that the crank arm bolts are tightened to the recommended torque specifications. Shimano suggests tightening the crank arm bolts to around 40 Nm.
  • Check the bottom bracket: Inspect the bottom bracket for any play or excessive wear. If there is noticeable play or difficulty turning the bottom bracket, consider replacing it.
  • Adjust the Q-factor: Make sure that the crankset is properly installed. Check that the crank arms are positioned symmetrically and that the pedals are aligned. You can adjust the Q-factor by opting for crank arms with different lengths or pedal spacers.

2. Noisy Pedals and Crankset

Another common issue with the Shimano FC-5700 crankset is a noisy pedal stroke. This can range from a subtle squeak to a loud creak that is distracting and often indicates a problem with the crankset or its components.

Possible Causes:

  • Loose crank arm bolts: As mentioned earlier, if the crank arms are not tightened correctly, they may produce squeaking sounds due to movement at the interface between the crank arm and the bottom bracket spindle.
  • Dirty or dry bearings: Insufficient lubrication or dirt buildup in the bearings can cause them to generate noise as they spin.
  • Pedal issues: Sometimes, the source of the noise might be the pedals themselves, particularly if they are not securely attached to the crank arms.

How to Fix:

  • Tighten the crank arm bolts: Ensure that the bolts holding the crank arms to the spindle are torqued to the manufacturer’s specifications. This will reduce any movement and eliminate squeaks.
  • Lubricate the bottom bracket: Remove the crankset and clean the bottom bracket thoroughly. Apply a light coat of grease to the spindle and bearings before reinstalling the crankset. This reduces friction and prevents squeaking.
  • Check the pedals: Inspect the pedals for any issues, such as loose pedal threads or damaged bearings. Tighten the pedals securely into the crank arms, and if necessary, replace the pedals or bearings.

3. Excessive Play in the Crankset

Excessive play or wobbling in the crankset is another problem cyclists may encounter. This can be a sign of either loose components or worn-out bearings, both of which hinder power transfer and can lead to further damage if not addressed.

Possible Causes:

  • Loose crank arm bolts: If the bolts are not adequately tightened, they can allow the crank arms to move around, which leads to play.
  • Worn bottom bracket: A worn or damaged bottom bracket can allow the crankset to move slightly, causing play in the system.
  • Improper installation: If the crankset was improperly installed or the bottom bracket wasn’t aligned properly, this can result in movement and instability.

How to Fix:

  • Check and tighten the crank arm bolts: First, ensure that the crank arm bolts are tightened to the correct torque settings. Shimano recommends a torque of 40 Nm for these bolts.
  • Inspect the bottom bracket: Remove the crankset and check the bottom bracket for any play or damage. If there is movement in the bottom bracket or the bearings are worn out, replace it with a new one.
  • Reinstall the crankset: Ensure the crankset is properly installed and aligned. A misaligned crankset can cause play, so double-check all components during reinstallation.

4. Chain Dropping or Skipping

Chain drops or skipping on the Shimano FC-5700 crankset are typically caused by issues with the crankset installation, derailleur setup, or chainline. This can lead to a loss of power during pedaling and could cause damage to the drivetrain components.

Possible Causes:

  • Misaligned chainline: If the chainline is off, the chain may not engage properly with the chainrings, causing skipping or dropping.
  • Loose crankset or bottom bracket: If the crankset or bottom bracket is loose, it can cause misalignment between the chain and the chainrings, resulting in the chain dropping or skipping.
  • Worn chainrings: Over time, chainrings can wear down, especially the teeth, which can cause skipping or chain drops if the chain is no longer properly engaged.

How to Fix:

  • Check the chainline: Ensure that the chainring is aligned with the cassette in the rear. Use a chainline checker tool to verify proper alignment.
  • Inspect the crankset and bottom bracket: Check for any looseness in the crankset or bottom bracket. Tighten all bolts and ensure the bottom bracket is in good condition.
  • Inspect and replace worn chainrings: Check for any visible damage to the chainring teeth. If the teeth are worn or damaged, it’s time to replace the chainrings.

5. Crankset Flex Under Load

Flexing of the crankset under high pedaling loads is a common concern, especially among competitive cyclists. While this issue is often less noticeable to recreational riders, it can result in inefficient power transfer during high-intensity efforts.

Possible Causes:

  • Crankset material: The Shimano FC-5700 is made from aluminum, which, while lightweight, can experience flex under high load if not designed for maximum stiffness.
  • Improper installation: Incorrect installation can lead to slight misalignments, which may cause flex when under load.
  • Over-tightening bolts: While tightening the crank arm bolts too much can cause stress fractures or damage to the crankset, under-tightening them can also lead to flex due to insufficient contact pressure.

How to Fix:

  • Ensure correct installation: Make sure the crankset is properly installed and the bolts are tightened to the recommended torque. A correctly installed crankset should not flex under load.
  • Upgrade components if needed: If you notice flexing under intense pedaling, and it affects your performance, you might consider upgrading to a more rigid crankset made from carbon or stiffer aluminum materials.

In conclusion, troubleshooting common issues with your Shimano FC-5700 crankset is essential for maintaining smooth and efficient power transfer. Regular maintenance, correct installation, and prompt addressing of any issues like loose bolts, worn components, or improper alignment can help ensure your crankset performs optimally for years to come. By following these tips, you can solve the most common problems associated with the FC-5700 and get back to enjoying your ride with maximum efficiency.