Front Derailleur

The front derailleur consists of a cage that can move back and forth and from side to side. As it does so, it moves the chain between chainrings. It is attached to the frame, usually by a clamp surrounding the seat tube. There are different types of front derailleurs, the most notable differences include the type of mount and the direction that the cable pulls.

**Note: When using the barrel adjuster to change cable tension: counter-clockwise = increases the wire tension = towards bigger sprockets; clockwise = decreases wire tension = smaller sprockets.

The four front derailleur adjustments:

1. Height
   
   • Height is the principle factor in how well it will shift. Best performance results from the very lowest position that still barely keeps the cage from hitting the chainring teeth. A 2mm clearance between the bottom of the outer cage plate and the teeth of the large chainring is often recommended.
     
   1. Shift to the outermost chainring and rear sprocket
      
   2. Common front derailleurs need a 5mm allen key or 8mm box wrench to loosen the band-clamp bolt
   3. The outer cage plate must be positioned over the largest chainring when viewing height
   4. Tighten the clamp so that it is secure, but loose enough to move around with your hand
   5. Position the bottom of the derailleur cage as close to the largest sprocket teeth as possible so that it still clears. Move on to setting the angle.
      
2. Angle
   
   • This is set by looking down at the cage from above. This can be tricky and require some patience, as the shape of the derailleur cage is often not straight. You must position the outer plate of the derailleur cage parallel to the chainring so that the chainring sits equidistant and parallel to the cage plates.
   1. After following the above instructions for height, sight the chain from directly above to see if the outer cage plate and chainwheel are parallel.
      
   2. Rotate as needed and secure the bolt when you're done
3. Limit Stops
   
   • The L-screw controls inward-most travel and the H-screw controls outward-most travel; just like the rear derailleur. On older derailleurs, the low-gear limit screw is closest to the frame, but some newer models have reversed the screw's positioning.
4. Indexing Adjustments
   
   • Not all front derailleurs have an index setting. If the front shift lever is friction, there is no index setting.
   1. Shift to middle chainring and innermost rear sprocket
   2. View gap between inner cage plate and chain. Gap should be as small as possible without rubbing the chain.
      
   3. To reduce gap, increase wire tension by turning barrel adjuster counter-clockwise.
   4. If the chain is rubbing the cage, increase gap by lessening wire tension by turning barrel adjuster clockwise.
   5. If the adjuster is all the way in or out and no adjustment is possible, reset inner wire tension. Shift to innermost chainring and loosen inner wire pinch bolt. Turn in the barrel adjuster almost all the way clockwise. Pull wire gently with third-hand tool and tighten pinch bolt. Repeat steps 1 - 4.
   6. Test shift to all 3 chainrings.