Try loosening the high limit screw on the front derailleur in 1/8th turn increments... also, recheck the cable tension when the chain is in the lowest chainring. However, don't go too tight on the cable or else you may run into problems with the chain going back down to the smaller rings. Sometimes I have to loosen the high limit screw (big ring) more than I like to get it to shift up well. Usually if it's loosened within reason, the chain won't shift off the crank and onto the pedals. Hope that helps!