These cranksets:
https://bike.shimano.com/en-EU/product/component/tiagra-4600/FC-RS400.html
https://bike.shimano.com/en-EU/product/component/shimano/FC-R460.html
https://bike.shimano.com/en-EU/product/component/cyclocross-and-onroad-hydraulic-diskbrake/FC-CX50.html

All have 110mm bolt-circle. The first comes as 50/34T, the second has options of 48/34T & 46/34T, and the third with 46/36T.

I’m just checking if there’s anything that would stop me fitting different sized aftermarket rings on any of them (whichever I can get my hands on), e.g. 48/33T?

It just seems odd that Shimano don’t simply make one single model with the various double-chainring combinations.

Thanks in advance! :^)

The pins and shifting ramps on Shimano rings are designed to work in matched pairs. If you look closely at a Shimano chain ring it will have a tooth count and also a letter marked on it which you look up in a table to find the matching ring it is designed to shift best with. You can mix and match rings but they won’t shift as nicely.

Ah cool, thanks. If I went with a non-Shimano big ring it’d probably not have the fancy shifting ramps of matched Shimano pairs, just the pins and maybe a generic ramp. Just so long as there’s nothing odd about the cranks themselves that means they can only take the rings they’re originally provided with & any old normal 110BCD rings will still fit, any of the above chainsets should be OK.

Thanks.