I take it that your talking about the front derailleur. There will be two mounting issues, up\down the seatpost, and the axis (parallel to the chainrings). There is also the cable tension issue to resolve. Then finally there will be the limit screw adjustments. My hybrid is equipped with an adjuster on the handlebar shifter for the front gears, where the cable comes out of the shifter. It is called a barrel adjuster. I can use this to trim the adjustment on the fly if it gets noisy. If you can, visit the park tool website for info on your front derailleur set-up.