I have made a few alterations to my much-loved Specialized Tricross Sport over the years. The main one being switching to a disc brake at the front, which also required a replacement carbon fork. The improvement in stopping power was undoubtedly worth the money, though.
I've recently been pondering whether to switch to a compact chainset. A play with Excel suggested that I'd only lose the very lowest ratio by changing from the OEM 30-39-50 triple to a 34-50 double. I had an idea that I could experiment by just putting a 34T ring on the triple crank, but that seems to be ruled out by the non-availability of 34T chainrings with either a 74mm or 130 mm bolt circle.
The next least disruptive approach would seem to be sourcing a 9-speed double crankset - either a used Tiagra of the same vintage as the bike, or a modern Sora. The kicker seems to be the cost of replacing the triple STI shifter with a double: I never realised how much those things cost on their own! Would it be wholly daft to try to run the double crankset with the triple shifter, and just use the top and bottom range adjustment screws on the triple front mech to avoid shifting off the rings? Or could I run a double front mech with the triple shifter? I am also unsure of whether I'd need to swap out the BB.
I suppose that the 'proper' way to do it would be to source a whole new drivetrain, such as the latest Tiagra 10-speed. That would obviously cost a fair bit more (although even taking the cheapskate route of just swapping the crankset I would spring some more cash to replace the worn cassette and chain as well). Sourcing the individual components of would would be more or less a complete drivetrain does start to rack the bill up in to three-figure territory (although I was surprised to see that if I shop around I can buy a full 10-speed Tiagra groupset for not much more, which would leave me with a pair of brand new road brakes that I could perhaps sell to recoup some of the cost).
The purist approach would probably be to invoke the n+1 rule and buy a new bike. But I actually really like my Tricross. I built it up myself from the delivery box, and there's just nothing about it that niggles me
apart from the occasional lure of shiny new "bits".
Post edited at 11:29