Originally Posted by
GeoKrpan
If you use an MTB shifter with your road front derailleur and crank it will work if it is a two chainring crank.
If it's a triple chainring crank it will work on two of the chainrings but not all three. You'll have to choose between the inner and middle chainring, or the middle and big chainring.
What GeoKrpan means is Shimano MTB shifters are not compatible with Shimano road front derailleurs; the cable pull is different. I've heard it can work with a double, but it won't be precise as the cable pull will be off. However, Shimano does make several front derailleurs that work with both the larger road chainrings and MTB shifters; IRD makes one also.