Shimano fd-m191 front derailleur adjusting height and angle

[DaveM]

(07-19-2010, 06:44 PM)erdem Wrote:  
if there is interference between the chain and the front derailleur inner plate at the largest chainring. tighten the top adjustment screw clockwise (about 1/8 turn).

This does sound backwards, but since it is quoted out of context, I can't be sure what they're trying to say.

I think you may be overthinking how this works. The two limit screws are just stops that prevent the derailleur from moving beyond a certain point. The inner one stops the der from going in so far that the chain falls off to the inside. The outer stops the der from going too far out and pushing the chain off the outer chainring.

the cable tension is what holds the der in position most of the time. The limit screws only matter when there is no (or very little) tension on the cable (so the der is resting on the inner stop). Or when you push the shifter all the way in so the der is forced against the out stop.

My normal process is to:
- put the chain on the inner rings in front and in back and adjust the inner limit so you get a couple mm gap between the cage and chain (making sure there is no tension on the cable.
- put the chain in the outer rings (front and back) and set the outer limit for a couple mm gap no matter how much pressure you put on the shifter.
- then adjust the cable tension so you get good shifting between the gears.

Note that most of the time, when the shifter is in the innermost position, the cable should not really have much tension on it. Usually you just pull it tight enough to take out the slack. But if you're using a tool to put tension on the cable when the der is in the inner position, you are almost definitely putting too much tension on it.