This is why the new crank sit too far out...... Measure the chainline from the center of the seat tube to the middle of the two chainrings, it should be approx 43.5mm..... If not subtract 43.5 from the figure you measured, double it then subtract that number from your current spindle length, and that is the length spindle you need.

Example: Current chainline 47.0mm------ 47.0 - 43.5= 3.5..... 3.5 x 2 = 7.0..... 7.0 - 115 = 108...... You would need a 108mm spindle. This is just an example.