Originally Posted by
Bonts
This bike has no BB, crank, or cassette. I was under the impression that as long as all the parts are of the same standard (shifting increments, chain type, etc) it’ll work fine. Is that not the case?
I'd never bet on it.
My main issue is you seem to be focused on the crank only. And the name of a group. Shimano 105 has been around for a long time in many different versions. Earlier 105 cranks for lesser numbers of sprockets on the rear may not play well with components made for 11 or 12 speed groups. They might still work. But maybe not work at the peak performance they would have when all components are from the same series and same version.
I'd start off by choosing whether you do or don't want electronic shifting. Then whether or not the bike frame has mounts for disc brakes. Then how many speeds you want on the rear. Then choose a group that best matches what you want. Not just a crank.
Disc brakes on road bikes have become a standard for newer higher to mid level component groups. And most better wheel sets are now only designed for disc brakes. So you might already have some challenges, depending on what your goal is.