Join Date: Jun 2005
Location: Jackson, NJ
Bikes: Dawes Lighting 1000; Motobecane Nomad
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Thanks for the response. I'm referring to Sheldon "Click" Brown's:
# Clamp Position
The most critical adjustment of a front derailer is its attachment to the bicycle frame. This must be set correctly before you attempt to adjust the limit stops. There are two variables, angle and height.
* Angle of the front derailer is judged by looking down on the cage from above. Modern front derailers have very subtly shaped cages, so it is not always easy to tell when the ideal adjustment has been made. In general, the centerline of the cage should be parallel to the centerline of the frame. Rotating the derailer so that the back of the cage is farther out will sometimes improve shifting to the small ring of a triple by preventing overshifting, but may cause increased need for trimming on the larger rings. It may also cause the crank to strike the cage.
Rotating the derailer so that the front of the cage is farther out will help reduce the need for trimming on the large chainwheel, and will provide crisper downshifting, but with a greater tendency to overshift on the inside. This may be appropriate on bicycles equipped with an anti-derailment device.
* Height of the front derailer is a principal factor in how well it will shift. Manufacturers commonly recommend 2mm clearance between the bottom of the outer cage plate and the teeth of the large chainwheel. This is a bit of an oversimplification. Best performance will result from the very lowest position that still just barely keeps the cage from hitting the chainwheel teeth.
The lower you can get it, the better it will shift, and the less you will need to trim the front derailer.
I've made those adjustments and it now will downshift, but it's very slow, three revolutions or even more
. I have now literally spent hours working on this problem.