Recently I switched to FSA K-Force compact 50/34 cranks on my Specialized E5 S-Works. I also bought an FSA C-16 derailleur because I'd heard of problems with the compact cranks and normal derailleurs. My LBS installed the cranks and attempted to install the C-16, but couldn't get smooth shifting. The guy said "it just didn't work." They put my Ultegra 6600 derailleur back on and claimed that Ultegras work fine with compact cranks.
Since then I've had nothing but problems. Warming up on the trainer before races I often can't get into the big ring, and I occasionally experience that while riding. Shifting is fine on a work stand. Today I had to bail out of a race because I couldn't shift into the small ring. Tonight I spent several hours trying to work out the shifting. I reinstalled the C-16 and it didn't seem to be any better, so I went back to the Ultegra.
Here's the problem - the limit screws seem to be very sensitive. I can't shift onto the big ring, so I twist the limit screw a quarter of a turn and then it overshoots the big ring. Same with the smaller ring - it either won't shift down or it blows right off into the bottom bracket. I've adjusted lots of front derailleurs in my life, usually it's a trivial operation. But something just isn't right with this compact. I followed some instructions on FSA's web site suggesting that I move the derailleur up higher than normal (I seated it about 4 mm above the crank instead of the typical 2 mm). Eventually I got it so the shifting was workable on my stand, but 9 times out of 10 I can't get into the big ring while on the road. When it does shift up it chews and spits for several turns before locking on.
Any advice? Unless I'm missing something obvious or there's a secret trick, I'm ditching these compact cranks and going back to my 53/39.
Since then I've had nothing but problems. Warming up on the trainer before races I often can't get into the big ring, and I occasionally experience that while riding. Shifting is fine on a work stand. Today I had to bail out of a race because I couldn't shift into the small ring. Tonight I spent several hours trying to work out the shifting. I reinstalled the C-16 and it didn't seem to be any better, so I went back to the Ultegra.
Here's the problem - the limit screws seem to be very sensitive. I can't shift onto the big ring, so I twist the limit screw a quarter of a turn and then it overshoots the big ring. Same with the smaller ring - it either won't shift down or it blows right off into the bottom bracket. I've adjusted lots of front derailleurs in my life, usually it's a trivial operation. But something just isn't right with this compact. I followed some instructions on FSA's web site suggesting that I move the derailleur up higher than normal (I seated it about 4 mm above the crank instead of the typical 2 mm). Eventually I got it so the shifting was workable on my stand, but 9 times out of 10 I can't get into the big ring while on the road. When it does shift up it chews and spits for several turns before locking on.
Any advice? Unless I'm missing something obvious or there's a secret trick, I'm ditching these compact cranks and going back to my 53/39.