@elrey - thank you kindly. Did a hard effort 41 miler yesterday. Just keep loving this bike more and more. Stopped for water and got some great compliments on the paint.
Things in the pipeline:1/ Wheels
Some original EDGE 1.25 rims (the light ones before they beefed them up for "clyde" riders") laced to Dash or other stupid-light hubs. The ENVE 3.4 tubulars are fantastic if a smidge porky.2/ New Crank?
Running a ROTOR 3D+ SRM w/ Praxis rings, which weighs 688g w/o the bottom bracket. The bottom bracket (ROTOR 4630 Ceramic) weighs 102g.
I could cut > 120g if I went with a THM M3 SRM and bottom bracket. Dunno how their rings will shift with the Di2, though. The Praxis rings are *very* nice. I won't give up my SRM. 3/ New Brakes?
I've been considering going back to a pair of EEs. I had the original version on my Colnago EPS and didn't ever feel that they worked as well as the (at the time) 7900 brakes. Apparently the new version is optimized for the level pull of the 7900 / 9000 levers and worth another try.
Pair of 9000 brakes comes in at 295g with pads. The EE brakes advertised weight is "less than 200g", so that's a possible 100g weight saving. I assume that advertised weight is without pads, so the difference is likely smaller.
Upside of all of the above changes is that the Colnago is back down to a frame, fork, headset and seatpost, so it needs a grouppo anyway. Opportunity to hand-me-down. Crapload of money, though, when I'm in the midst of a 'cross build.
So many pretty bike parts...