Hi all,

I'm having some difficulty with the shifting on my bike on both the front and rear derailleur. I can't get the shifting dialled in on the rear derailleur with the barrel adjuster. I can either get pretty good shifting on the low end of the cassette or the high end of the cassette but not both. For example, if I get the shifting dialled in on the low end of the cassette then it shifting from the 23t cog to the 25 takes doesn't happen smoothly. Plus down shifting back to the 23 is unreliable. Sometimes downshifting doesn't do anything, other times it does but then when observing the chain on the cog it looks like the chain keeps trying to move back up. The only way to reliably stay on the 23t cog is to down shift to the 21 and then back up to the 23. Additionally the whole system is very sensitive at this point, slightly adjusting the barrel adjuster a little bit one way or the other noticeably degrades shifting performance more so than I have ever noticed on other bikes with minor barrel adjustments (e.g. 1/4 turn).

On top of that, I'm having difficulty with shifting on the front derailleur. If I try to downshift from the 50t ring to the 39t ring, it often skips all the way down to the 30t ring, and then shifting up usually requires two shifts, and to get it ideal it's usually two full shifts plus some trim adjustment.

Now I replaced the whole drive train (Ultegra 6600 shifters, Ultra 6703 FD, 6700 RD, 5703 Crankset) a few weeks, so I wonder if perhaps the issue is that the drive train wasn't completely properly installed. The front derailleur never shifted well (it would over downshifted maybe 10% of the time almost immediately, but I didn't down shift a lot so it wasn't super noticeable), but the rear shifting was pretty good.

It has occurred to me that this could be an issue of a bent derailleur hanger - I park my bike at work in a clearly inadequately bike parking situations, so I've wondered if someone has banged their bike into mine possibly bending the hanger. How hard would the bike need to be banged in order to cause that problem? Or is it possible that the upgraded drive train wasn't completely properly installed in the first place? I doubt it's a problem with the cables since they were also replaced with brand new cables, but I guess that's possible. Or could this be a compatibility problem between the 6600 brifters and the 6700 derailleurs?

I'm not going to do the work myself, I am going to go back to the shop that did the work, but I'm trying to inform myself about this as much as possible. They have said that they guarantee their work, but how can I determine if the problems I'm experiencing with the shifting are a function of a poor installation versus something that has happened to the bike in the interim (e.g. my theory that someone may have banged into it). How much should I be responsible for paying to getting the shifting to work properly?

Thanks,
Brad