Front derailleur cable tension too high with Acera shifter and Ultegra derailleur I'm trying to install some Acera trigger shifters to use with my Ultegra derailleurs.  The rear derailluer/shifter combo (8 speed) is working great.  The front however (3 chain rings) seems to have a problem.  I have to push extremely hard on the shifter to move from the lowest chain ring to the second, and it is almost impossible to apply enough force to get from the 2nd to the 3rd chain ring.  I actually broke a cable trying to go from the 2nd chain ring to 3rd.  I've tried messing with the barrel adjusters at the down tube and at the shifters to change the cable tension but it doesn't seem to have much effect.  It almost seems like there is not enough mechanical advantage.  Is it possible that the combination of the Acera trigger shifters and the Ultegra front derailleur is not a good one?
I just figured it out... the front derailleur cable wasn't going over the leverage tab on the derailleur correctly.  I had it going under and that's why there was no leverage going into the largest chain ring.  Here is an image of what I mean by leverage tab:

http://hostelshoppe.com/PDF/ftder_cable_routing.pdf