SoSmellyAir

Thanks. Have thought along similar lines, i.e., 48/32 chain rings (like an eTap AXS bike) with the 12-25 cassette. Having only used the 12T cog once or twice since switching to the Ultegra cassette, I doubt I need more than a 4:1 top end. And, at the bottom end, 32 over 25 (1.28) splits the difference between the 34 over 25 (1.36) that I am currently getting by on (side benefit: firmer legs) and the 34 over 28 (1.214) original goal of the custom cassette. But I do not have the experience or the required tools to remove crank arms, which seems to be necessary to swap at least the small chain ring. But definitely keeping that option in mind when it comes time for new chain rings.