Originally Posted by
twowheelies
Can I change my DA 7700 53/39 crankset to the DA 7700 53/39/30, to get a little more help for my aging joints on those climbs? What mods would i have to make, any? Front derailleur? Wider bottom bracket maybe? Bike is a Bianchi San Lorenzo from early/mid 2000s.
Thanks as always for the help.
For a 53-39-30 triple, Dura Ace 7700 specified a triple-specific front derailleur (FD-7703) and triple-specific shifter (ST-7703 L). You wouldn't necessarily need to use those exact parts, but for indexed shifting on a triple, you'll want a front derailleur designed for road triples and you'll need a compatible triple-specific shifter to actuate it. You might be able to get your existing FD to work alright if you instead use a friction shifter.
Bottom bracket will depend on what's in there now and what crank you switch to...
Which rear derailleur do you have, and what cassette will you be using? If you have the short-cage RD-7700-SS instead of the RD-7700-GS, you might be pretty short on chain wrap with a wide-range triple.