Front derailleur and crankset C-447

The allowable combinations of front derailleurs depend on the difference in the number of teeth of the gears and the shape of the front derailleur plate.

If the conditions given below are not satisfied, then the desired shiftability may not be obtained.

FC (largest chainring) - (smallest chainring) ≤ FD (high and low capacity)
FC (largest chainring) - (middle chainring) = FD (allowance of difference in teeth number between top and middle)

Each front derailleurs and the number of teeth of corresponding cranksets are given in the compatibility chart.