Originally Posted by
purdyd
I suspect it is flexing in the carbon rim and the clear coat Is not flexible enough and cracks.
i don’t know if this is just me and I can do something different or just an issue with this particular shimano wheelset
I think this is the issue. The asymmetric braking force from the disc is probably increasing the spoke tension, causing the nipple to flex. The clearcoat can't take it.
I think it's a fundamental issue with these wheels and you. My advice would be get the wheels warrantied, but immediately sell them (as new unmounted) and replace with something else. For whatever reason, you and these wheels don't mix.