Adjustments to the front derailleur are required when the derailleur drops the chain off the side of the chainrings (inside or outside) or when one chainring cannot be reached.
1. Check that the derailleur cage is perfectly parallel to the chainrings. Allow about 1/8 inch, or 2 mm verticle clearance between the chainring teeth and the bottom of the cage. Disconnect the cable, loosen the clamp bolt and twist the derailleur into position.
2. With the cable disconnected, shift the rear derailleur onto the largest cog. Using the 'L' limit screw, align the derailleur so that the inside plate is 1/8 inch (2mm) from the chain. Reattach cable to derailleur, removing slack with your hand.
3. Shift the front derailleur to check the indexing of the shifter, making small adjustments at the anchor bolt as necessary. If shifting is correct, turn 'L' limit screw1/2 turn counter clockwise.
4. Shift chain to smallest cog and largest chainring. If chain rubs the
outer plate of the derailleur, turn the 'H' limiter screw clockwise or make
adjustment at cable anchor bolt.
5. When derailleur position is correct on large chainring, turn 'H' limit screw
clockwise until resistance is met. If large chainring cannot be reached, check
cable tension then try to turn 'H' screw counter clockwise.
A finely tuned bicycle is a pleasure to ride. The bicycle is basically a simple machine.
Knowing how to diagnose potential problems will help you prevent
mechanical problems that may spoil your ride.
If you ever have any doubts about your personal repairs or condition of your bike, please take it to your local independent bicycle dealer for service, parts and advise.
- 5mm Hex wrench
- Phillips screwdriver
- Cable/housing cutter
to go to Park Tools Instructions