How to Install, Adjust, and Maintain the Shimano ST-6800 Shifters

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in Shifters, Shimano, Ultegra

The Shimano ST-6800 [paid link] shifters are part of Shimano’s Ultegra 6800 series, a highly regarded component group known for its precise shifting and durable performance. If you are looking to install, adjust, or maintain these shifters to ensure smooth gear changes, you’ve come to the right place.

This guide will provide you with a comprehensive step-by-step process for each task, helping you achieve optimal performance from your Shimano ST-6800 [paid link] shifters.

Tools Required

  • 5mm Allen wrench [paid link]
  • Phillips screwdriver
  • Torque wrench [paid link] (3–6Nm range)
  • Shimano-compatible brake and shift cables
  • Cable housing
  • Cable cutters
  • Lubricant (light oil or grease for parts)
  • Rag for cleaning
  • Shimano ST-6800 [paid link] shifters (left and right)
  • Spacers (if needed for specific bike setups)

Installation of Shimano ST-6800 Shifters

1. Prepare the Bike

Before you start installing the Shimano ST-6800 shifters, make sure your bike is in a stable position. You may want to place it on a repair stand or flip it upside down to have easy access to the components.

2. Install the Brake Levers

The Shimano ST-6800 shifters also double as brake levers, which means you’ll need to position them properly on your handlebars.

  • Left shifter (brake lever): This lever is for the front brake. Slide the left shifter onto the left side of your handlebars.
  • Right shifter (brake lever): Similarly, slide the right shifter onto the right side for the rear brake.

Ensure the shifters are positioned comfortably, with enough space for your hands to comfortably grasp them without interference.

3. Attach the Shifters

  • Use a 5mm Allen wrench [paid link] to tighten the bolts securing the shifters onto the handlebars.
  • Ensure the shifters are aligned straight with the bike frame.

4. Install Brake and Shift Cables

Now that your shifters are in place, it’s time to install the cables.

  • Brake cables: Feed the brake cable through the lever’s housing guide, and attach it to the brake caliper using the standard brake installation procedure.
  • Shift cables: For the front and rear shift cables, run them through the cable housings, ensuring the cables are properly seated in the shifter units.

5. Set the Position of the Shifters

Once both cables are in place, ensure that the shifters are in the correct position relative to the handlebars. This helps with the natural operation of the levers and ensures smooth shifting.

6. Test the Shifters and Brakes

Before you finalize the installation, check to make sure that both the brake and shift levers are functioning properly. Pull the brake levers to ensure they’re responsive, and test the shifting mechanism for smoothness.

If you’re unsure about the cable tension or want to adjust the reach of the brake levers, continue to the next sections.

Adjusting Shimano ST-6800 Shifters

Shifter Cable Tension Adjustment

To achieve perfect shifting performance, the cable tension of your Shimano ST-6800 shifters must be just right.

  1. Shift to the smallest cog (in the case of the rear derailleur) or the smallest chainring (front derailleur).
  2. Using a 5mm Allen wrench [paid link], locate the barrel adjuster near the shifter and turn it counterclockwise to decrease tension or clockwise to increase it.
  3. Make fine adjustments to the barrel adjuster until the shifting is smooth and crisp, with no hesitation or skipping between gears.

Brake Lever Reach Adjustment

  1. Locate the small screw near the brake lever on the Shimano ST-6800 shifters.
  2. Turn this screw to adjust the distance between the brake lever and the handlebar, ensuring that the lever is at a comfortable reach for your fingers.
  3. Test the brake lever reach by squeezing the brake levers in a riding position to ensure it feels comfortable and responsive.

Front and Rear Derailleur Limit Screws Adjustment

The Shimano ST-6800 shifters work in conjunction with the front and rear derailleurs, and the limit screws control the outer and inner limits of the derailleur’s movement.

  1. Rear derailleur: Using a Phillips screwdriver, adjust the high and low limit screws on the rear derailleur. These screws determine the maximum travel of the derailleur, preventing the chain from overshooting the smallest and largest cogs.
  2. Front derailleur: Similarly, adjust the limit screws on the front derailleur to ensure the derailleur shifts smoothly between chainrings without overshooting.

Maintaining Shimano ST-6800 Shifters

Regular Cleaning

To keep your Shimano ST-6800 shifters in top shape, clean them regularly. Dirt, grime, and moisture can cause poor shifting performance.

  • Clean the shifters: Wipe down the shifters with a damp rag to remove dust and dirt.
  • Lubricate the cables: Apply a small amount of lubricant to the shift cables every few months, especially if you ride in wet conditions.

Cable and Housing Maintenance

Over time, cables and housing can wear out and affect the shifting performance of your Shimano ST-6800 shifters.

  • Inspect cables: Check for fraying or kinks in the cables. Replace them if necessary.
  • Inspect housing: Over time, housing can become compressed, causing friction that impedes smooth shifting. Replace any damaged or worn-out housing.

Brake and Shifter Lubrication

Regular lubrication of both the brake and shifting mechanisms is essential for smooth operation.

  • Brake lubrication: Apply a small amount of lubricant to the pivot points of the brake levers.
  • Shifter lubrication: Use a light oil to lubricate the shifter mechanism inside the shifters. Avoid using excessive amounts of oil to prevent buildup that could affect performance.

Troubleshooting Common Shimano ST-6800 Shifter Issues

1. Unresponsive Shifting

If the shifting feels unresponsive or sluggish, check the following:

  • Cable tension: Ensure the cables are properly tensioned.
  • Dirty cables: Clean or replace cables if they appear grimy or worn.
  • Limit screw adjustments: Check the derailleur’s limit screws for proper adjustment.

2. Slipping or Skipping Gears

If you experience skipping or slipping while pedaling:

  • Check the derailleur hanger alignment: An out-of-alignment derailleur hanger can cause shifting problems.
  • Inspect the cassette: A worn-out cassette may cause gears to skip. Replace if necessary.

Conclusion

Installing, adjusting, and maintaining your Shimano ST-6800 shifters is essential for ensuring smooth, reliable performance. By following the steps outlined in this guide, you can optimize your shifting system and enjoy better control, speed, and efficiency on every ride.

Remember, regular maintenance and troubleshooting will help you keep your Shimano ST-6800 shifters running like new for years to come. Always stay proactive with your bike’s upkeep to prevent future issues.