Setup / Adjust (index) bicycle front derailleur for better performance

Описание: Ever had this problem? You go to shift your bike front derailleur and the chain doesn't move off the small chainring? Or when you shift down from your large to the chainring, the chain rubs against the inner plate of the derailleur and the inner limiting screw has no effect no matter how much we turn it counter clockwise? These are problems with the front derailleur cable tension. Sometimes they fix these bicycle problems with the front barrel adjuster but other times we need to fall back and re-index the front derailleur. Let's see how this is done.

First let's talk about how the front derailleur of the bicycle works. The front mech has a spring that move it over the small chainring. The tension of the front derailleur cable counters this and pulls the derailleur toward the large chainring. It's this balance that allows shifting. To index (adjust front derailleur), the only bicycle tools you'll need are a hex wrench of appropriate size and long nose pliers (or some type of pliers to put tension on the cable.

1. Loosen the front derailleur pinch bolt
2. Screw the barrel adjuster for the front derailleur all the way in (clockwise) and then out about 1/2 turn (counter clockwise). The barrel adjuster may be on the down tube or up by the shifter depending on your components.
3. While in the small chainring, shift the rear to the largest cog. Adjust the low limiting screw (usually the one closest to the frame) such that the inner plate of the front derailleur is about 2 mm from the chain.
4. Shift the rear to the smallest cog. Move the front derailleur by hand and make sure the inside of the outer plate moves about 3-4 mm beyond the large chainring. If not, adjust the outer limiting screw (the one closest to you) such that this is the case. We'll fine tune the outer limiting screw at the end if needed.
5. Place the cable below the front derailleur pinch bolt and pull firmly but don't use gorilla force. While doing this, tighten down the pinch bolt.
6. Try shifting from small to large chainring. If the chain moves toward the large chainring but does not engage, either the derailleur is limited by the outer limiting screw or there is not enough tension in the front derailleur cable. Make sure the derailleur can move beyond the large chainring. Release the derailleur pinch bolt while you pull slightly on the cable - then re-tighten the pinch bolt. Repeat, if need, until the chain shifts nicely to the large chainring.
7. Finally, try shifting the front derailleur. Re-adjust the outer limiting screw if there is chain rub in the large chainring and larger cogs or if the chain falls off to the outside. (**card** see our video in the upper right)

Check the the bike gears of the front and rear derailleur during routine bike maintenance or bike repair.