How to adjust Shimano road front derailleurs:
All front derailleurs have the same basic adjustments. You have a low limit screw, a high limit screw, and the cable anchor adjustment.
The first step is to adjust the position of the derailleur. Loosen the derailleur bolt and move the derailleur to between 1 and 3 mm off the top of the teeth to the bottom of the derailleur cage. Make the outer cage parallel with the big chainring.
Before going to the next step make sure the barrel adjuster is turned all the way in (clockwise) to release any tension that may be in the cable and leave room to adjust it later. Next, shift the rear derailleur into the largest cog on the back, and have the front derailleur in the small cog.
Now, set the inner limit. The inner plate of the derailleur cage should be as close to the chain as possible without actually touching it. That means the inner limit screw should be tightened. Turn the pedals to make sure it isn’t touching the chain.
Adjust the cable tension. Pull the cable tight and tighten the cable anchor adjustment with an allen key. Shift the derailleur into the large chainring. You want a small gap between the chain and outer cage. Adjust using the upper limit adjustment screw. Now check by turning the pedals.
If you can push the derailleur cage out with your finger, the cable tension isn’t right. Back out the barrel adjuster to give the needed tension. Test to make sure the chain shifts and stays on nicely.