The Shimano FD-6700 [paid link] front derailleur, part of the Ultegra 6700 series, is a precision component designed for smooth, accurate shifting. However, it is also a derailleur that requires careful set-up and maintenance. Small errors during installation or adjustment can lead to poor performance, premature wear, or even component failure. This guide covers the most common mistakes riders and mechanics make with the FD-6700 [paid link] front derailleur and explains how to avoid them.
Incorrect Mounting Height
One of the most frequent mistakes with the FD-6700 [paid link] is mounting the derailleur cage too high above the big chainring. Shimano specifies a clearance of 1–3 mm. If the derailleur sits too high, shifting becomes sluggish and inconsistent. If it sits too low, the outer cage can rub against the chainring teeth, causing noise and unnecessary wear. Always measure carefully during installation and ensure the cage sits parallel to the chainring.
Ignoring Cable Tension Requirements
The FD-6700 is designed to work with Shimano’s specific cable pull ratio for 10-speed systems. Setting the cable tension incorrectly leads to delayed shifts or overshifts into the chain. Many riders mistakenly over-tighten the cable, which stresses the derailleur spring and can cause long-term damage. Correct tension should allow crisp movement without excessive force at the lever. Fine adjustments should always be made with the barrel adjuster, not by over-pulling the cable at the anchor bolt.
Improper Limit Screw Adjustment
Limit screws control the derailleur’s range of movement, preventing the chain from overshooting onto the crank arm or dropping into the bottom bracket. With the FD-6700, setting the low limit too tight often causes chain rub in the small chainring. Conversely, setting the high limit too loose risks the chain overshooting on the big ring. Riders who skip this fine-tuning step may experience frequent chain drops, which can damage both the derailleur and chainrings.
Mismatched Chainline and Crankset
The FD-6700 was engineered to pair with Shimano Ultegra 6700 cranksets, optimized for a 43.5 mm chainline. Using incompatible cranksets or bottom bracket spacers changes the chainline, forcing the derailleur to operate outside of its intended range. This results in chain rub, sluggish front shifts, and premature wear on the derailleur cage. Ensuring component compatibility is critical to avoid long-term shifting problems.
Neglecting Frame Support Requirements
The FD-6700 braze-on version relies on a rigid mounting surface. On some carbon frames, Shimano requires a support plate or reinforcement to prevent flex. Ignoring this requirement can cause the derailleur to bend under load, leading to poor shifts and possible frame damage. Riders should always check frame specifications before mounting to avoid structural issues.
Overlooking Chain Compatibility
The FD-6700 is designed exclusively for 10-speed drivetrains. Installing it with an 11-speed chain, which is narrower, causes inconsistent shifting and excess cage rubbing. Conversely, using a 9-speed chain, which is wider, leads to clearance problems. Always match the derailleur with the correct chain for optimal performance.
Improper Cable Routing
Many riders overlook the importance of cable routing under the bottom bracket. The FD-6700 relies on smooth, friction-free cable movement. If the cable housing is cut too short or routed at a harsh angle, increased friction leads to heavy shifting and cable wear. Regular inspection of the cable guide and housing is essential to keep shifting smooth.
Skipping Regular Maintenance
Even when set up correctly, the FD-6700 requires ongoing maintenance. Dirt buildup in the pivot points leads to stiffness and reduced spring return. Failure to clean and lubricate the derailleur at regular intervals shortens its lifespan. Applying light lubrication to the pivots and checking cable condition ensures long-lasting, precise shifting.
Forcing Shifts Under Load
The FD-6700 performs best when shifts are made with reduced pedaling force. Forcing a shift under heavy load can bend the cage or stress the mounting bolt. This mistake often occurs during climbs when riders attempt to move into the small ring too late. Training yourself to shift early and ease pedal pressure during shifts protects both the derailleur and drivetrain.
Using Incompatible Shifters
The FD-6700 front derailleur is tuned to work with Shimano 10-speed STI shifters from the same generation. Mixing it with later-generation 11-speed shifters results in mismatched cable pull, which prevents accurate shifting. Riders who attempt cross-compatibility often end up with unsolvable shifting issues. Always match the derailleur with the correct shifter series.
Conclusion
The Shimano FD-6700 front derailleur is a high-performance component when installed and maintained correctly. However, it is also unforgiving of setup errors. Mounting height, cable tension, limit screw adjustment, and component compatibility must be handled with precision. By avoiding these common mistakes, riders can keep their FD-6700 shifting smoothly and extend its service life significantly.