the chainring on the r5 ca up there looks like it's carbon wth
Since the rest of the bike is a mix of high end weight weenie equipment (AX Lightness finishing kit / brakes) the Fibrelyte chainrings, I would suggest are another detail to get the weight down .. Also the cranks are Zipp proprietary 4 bolt fixing Vumaquad cranks so there's not a lot of chain rings available apart from custom.
Since the rest of the bike is a mix of high end weight weenie equipment (AX Lightness finishing kit / brakes) the Fibrelyte chainrings, I would suggest are another detail to get the weight down .. Also the cranks are Zipp proprietary 4 bolt fixing Vumaquad cranks so there's not a lot of chain rings available apart from custom.