Howdy all, I'm in the market for a new bike,(flat bar road) but the ones I like all seem to have the " new cross type" ie 50/34 cranksets. I have a Shimano FD-773 frt derailleur (flat bar triple) so all I need is a triple crankset. I would like to know if a 9sp triple crankset would work with a 10sp rear cassette, as they are much cheaper. I have heard that chainrings "do'nt care", as the front and rear derailluer are alredy 10sp capatible. For the curious, I am 50 and not as strong as I once was, and there are a lot of hills where I live. So the extra would come in handy. As for a flat bar, I had a incident with a table saw ... which hampers me with using a drop bar
2003 Specialized Hardrock, 2004 LOOK KG386i, 2005 Iron Horse Warrior Expert, 2009 Pedal Force CX1
Before committing to the bike, make sure that the flat bar front shifter can handle a triple crankset. I don't think there are "double" versions of the flat bar shifters but I may be wrong. You may also need to change the rear derailler to take up the chain slack when using the little ring.
Don't feel bad about using a triple at age 50. I'm 28 and have triples on both of my road bikes (and my commuter and mountain bikes as well).