Originally Posted by cyccommute

The front is slow and clunky because it is operated wrong. The front derailer depends on a spring to knock the chain off to the lower gears under torque. Shimano’s Rapidrise suffered from the same problem. The spring just isn’t strong enough to knock the chain off under high torque situations and, thus, the derailer just clatters against that chain until torque decreases enough that the spring can knock off the chain. If front derailers worked the same way as rear deraiers…i.e. the cable drags the chain off the larger gears to the smaller ones…the shifts on the front would be as lightning fast and efficient as the rear. Suntour made a few of the high normal front derailers (as did Shimano) that worked really well back in the days before pins and ramps on the chainrings...