Originally Posted by
Steve B.
I heard it was pushed by SRAM as they could never get a front derailer to work correctly.
I agree that was SRAM’s thinking but I disagree with SRAM’s thinking. SRAM front derailers are about the best shifting front derailers I’ve ever used. They are far superior to Shimano, especially at the higher levels. Shimano gets too clever when it designs the high end front derailers by narrowing them and sculpting them which makes them much more finicky to set up. They also use weaker springs which makes derailment more difficult under high torque situations like downshifts on step hills. They also just do stupid stuff with their fronts like the Shimano M592-E carbon fiber e-type front and the XTR that had independent inner and outer plates. The carbon fiber e-type was so flexible that it wouldn’t stay in gear.
SRAM stronger front spring moves the chain better on downshifts. It makes a far more satisfying “clunk’ when it downshifts and it
does shift crisply.
All that said, most front derailer suffers from a fundamental design flaw to begin with. Shimano tried to get people to embrace the Rapid Rise rear derailer which works the same way that the front does…i.e. the spring does downshifts. They didn’t work all that well for the same reason that the front has problems…it depends on the spring to move the chain under high tension. Front derailers should be high normal which means the spring works to do upshifts which are under lower torque. If the front derailer
dragged the chain to lower gears it would work far better. No more “clatter! clatter! clatter!” as the chain struggles to knock the chain off the larger gear. I had a high normal front long ago and it was a marvelous thing. Shifts were much easier under torque.