I haven’t seen anyone else put an XLPR groupset on a 1x TT bike – this forum seems to be the place for unconventional builds though - I think it works great! I am not too picky about cadence, generally average about 95rpm in races.
First of all, nice bike build, and thank you for the detailed post, and parts!!
I quote your post regarding gearing because I see very few people talking about this subject here, mostly I guess, because TTers like their gear gaps small so it won't impact cadence. Your aproach is very similar to mine: SRAM XPLR 1x12.
I like to compare bike builds (gear wise) to something I rode in the past: 12 speed Shimano Ultegra with 54-40 chainring and 11-30 cassette - resulting in 368% range, but with lots of overlapping gears and very small gaps. I use
https://www.gear-calculator.com/ for this type of comparison.
Using that Shimano gearing as comparison, a 50T and 10-44T XPLR cassette would give same maximum speed and a extra gear on lower speeds, but also much bigger gaps (ain't big a problem to me too) - 440% range.
Your setup results in a similar situation: 54T with 11-44T, same final speed and a bit more range on the lower side (compared to the shimano setup) - 400% range and pretty much the same bigger gaps except for one gap in the beggining of the cassette.
I think a 11-44 cassette is a better option because HG freehubs are much easier to find (at least where I live) compared to XDR ones, but it will limit you if you want smaller gaps down on the road (10-36T for example).
I guess a 10-36T cassette would be ideal, same range as shimano with controlled gaps, and since XPLR derailleurs can manage 10-36 cassettes, best of two worlds. I intend to keep an eye on the app for gear usage, and then tune the chainring size so I can stay most of the time on the middle of the cassette for better efficiency.
Oh and your tool box is vey neat!! I designed a similar one for a Cervelo frame once, to keep things from rattling, I put everything inside an old sock, very useful to clean hands too...
