Just heard back from FSA, and sadly it won't work. The tandem cranks and regular cranks use a different spindle. Ack.
So, I decided to go ahead and do a 48/32 double with a 11-32 cassette. Considering the FSA triple comes with a 30t small ring (traditional tandem gearing), I don't think 32t is outrageous. If we ever travel somewhere really hilly (we live in the prairie) I'll pop on an 11-40 with a roadlink. 48-11 still gets us to 31.5mph pedaling at 90rpm.
Originally Posted by
Chilepines
BTW - the new FSA Gossamer Road Double has many chainring size options, including 48/32 and 46/30. Since you have the FSA tandem set already, why not give FSA a shot at answering your question and let us know the answer!