One caveat about the RCA: it's BBright. It seems we can't have it all after all. Any weight savings made with the frame is paid back in crankset weight due to the limited selection of compatible cranks
, although the THM Clavicula is available with BBright solution, but it won't be the lightest. For a truly light build, I would've liked to have seen it BB30 with a Hollowgram SiSL2 SpiderRing option. Maybe a THM M3 with custom spider-less integrated chainring combo instead? If you go with a frame this light, you might as well go with the lightest components, especially since it isn't about the money anymore.
Would you trade flexy frame to get light cranks?
THM Clavicula's are quite nice. If I remeber mine where 340g/175mm/130mm BCD. AX's are too flexy, and I don't know similar weight but same stiffness cranks. I have those in my R5Ca. I ordered BBright versions from THM, but as bearing seem to sit over CF, not alloy, in their solution, least my ones, I made new bb housing and bondet that to frame. It was like +9g but as bearing is now 9mm more wide, stiffness should be better. Since THM's are not real Bbright cranks, why not...
I leaving this week for 2 weeks to Spain, and hoping to enjoy R5Ca there. Not the latest version, first one. (it's 5,7kg with Powermeter and training wheels/saddlle for riding 2000km/2 weeks, 4,7kg with ww-parts,Speedplay pedals/1x cage, used then as sunny ride/recovery bike, 56cm size) It's different, even other Cervelo's are nice, this beast is different. More response, better power transver etc. I know, hard to understand, but belive me, forget price, and pleace, go for test ride....and critice after that IF still you feel so. It's just fantastic frame.