Triple Ring Changes on Ultegra Setup?

Tom said:

My wife has a Cannondale set up as follows: Ultegra 9spd
52-39-30 in front and a 12-25 cassette.

We live in the mountains and I would like to change the
smallest front ring to a 26t if that is possible, as I
made a similar change to my Campy triple ring bike and
its great. I just don't know if that's possible on her
Ultegra, or if Shimano has another recommendation, such
as a 28t?

Yes, this works fine. For details, see:
sheldonbrown.comchainrings.htmlOpen ↗

Quoted message said:

Changing out the rear cassette would require a derailleur
change and I'm trying to avoid that cost.

That's not correct. You could go as far as 30 teeth in back
(our 13-30 "Century Special" cassette) with your present
derailer, maybe even 32, but that's a bit dodgy.

See: sheldonbrown.comk7.htmlOpen ↗

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