I'm looking at changing the groupset of my Bombtrack Beyond 1 from the stock SRAM Apex to the Microshift Sword 2x10 groupset. My main objectives are 1. better ergonomics, because I really don't like the Apex brifters, 2. A very low lowest gear, and 3. Since my height is at the lower end of the range that my frame size is made for, I want to try shorter crankarms (175 -> 170 mm).
I'm planning to use everything Microshift, including the 11-38 cassette, but I was thinking about using the Shimano CUES FC-U4010-2 crankset with 40/26T, in order to get a really low climbing gear. I'm mostly using my bike for bikepacking/touring in the Alps, so I usually carry additional weight and have long steep ascends.
The capacities of the derailleurs should match (max. 44 for the rear and max. 17 for the front derailleur), but I have some concerns about the chain line and the smaller chain ring:
The frame has a chain line of 49.5 mm, the crankset 48.8 mm and the Microshift derailleur 47 mm. Is this within a reasonable tolerance range?
Microshift states that the derailleur "allows you to run inner chainrings as low as 29T". Same question: is three teeth a reasonable tolerance range?
Thanks in advance for any experiences! I'll keep you updated if I decide to try it