I wonder if anyone knows the answer, but I give a try. I would like to use together a Shimano XT-M785 (10 speed) dyna-sys double crankset, a Shimano 105 5700 double front derailleur and a Shimano 105 5700 double shifter.
I read the description of the front derailleur on Shimano home page and according to it, the only limitation is the maximal difference (16 teeth) between the two chain rings.
I'm not sure that the 5700 front derailleur will handle the 26 teeth (or 28 teeth, but 26 should be better) inner chain ring (and with a 40 teeth large one). Could anyone approve it?
The other problem: The cable pull of a 10 speed double XT front derailleur is different from the 105 5700 double (that's why I have to use 5700 front derailleur).
I know that this difference is huge (about 30%) and I'd like to know if there is a difference between the chain ring distances in 105 5700 double cranksets and XT M785 double cranksets.
So do you think that a 10-speed MTB double crankset will work with a road 10-speed front derailleur? Will I have any problem with the chain line?
Or if you have any suggestions to use a 26-40 or 26-42 crankset with a Shimano 10 speed road front derailleur, please let me know.
Thanks for helping me!