Despite the apparent complexity, the front derailleur on a modern bicycle is fairly simple in design. The change in speeds occurs due to a change in the tension of the cable.
Instructions
Step 1
Wash the switch before adjusting, lubricate all moving parts. Check the condition of the tension cable. Replace it if it is worn out. If it is heavily soiled, clean and lubricate it (an unlubricated cable may cause incorrect gear shifting). Start tuning the front derailleur. To do this, you must use the full range of the rear gears, so adjust the front gear only after adjusting the rear.
Step 2
Loosen the switch mounting screws and cable. Position the frame three millimeters from the largest star and make it parallel to all the stars. Leave the speed as low as possible. Turn the screw labeled L until there is a one millimeter gap between the chain and the frame. Secure the cable in the groove with sufficient tension. Do the same with the screw marked H. Make adjustments on the shifter (speed selector).
Step 3
Adjust the position of the front derailleur relative to the bike frame. To set the angle of rotation in the horizontal plane, look at the frame from above: the center axis of the frame should be parallel to the leading sprocket. Shifting the front slightly towards the frame will keep the chain from slipping off the small sprocket. Install a limiter additionally. Adjust the position of the frame so that the chain is closer to the outside of the frame, but does not touch it when pedaling.
Step 4
Attach a chain to the small sprocket on the front wheel and the large sprocket on the rear wheel. Loosen the bolt that secures the cable. Screw in until it stops and slightly unscrew the drum located on the front derailleur lever. If you loosen the stopper too much, the chain may slide off when shifting. If the limiter is tightened too tightly, it will be impossible to switch to the small sprocket.
