Originally Posted by
Amesja
Would it be worth it to counter-bore/ream just the tiniest bit of the rim at the "pointy bit" of the lug so that it doesn't dig into the carbon and start this stress riser as easily? I'm thinking of just using a bit of 400-grit sandpaper to make sure there isn't a shear knife-blade of a corner at the lip there where the upward-pointing parts of the seat lug might cause an issue. a more rounded lip rather than a sharp 90-degree angle should help a lot and not be at all noticeable with the seatpost (either the carbon or another alloy) in.
I'd say no, and quantify that opinion by stating I don't believe it would make any real difference and because a Raleigh Competition is a fine vintage steed. I wouldn't modify that frame in any way just so I could put in a $35 carbon seatpost; in the end, the modification would still be there and affect value were you to ever sell it.
When I upgraded the Davidson to 8-speed and all-modern components, I thought about sticking a carbon post on that build. I guess I was trying to convince myself the failure I had was a one-off
So I get where you're coming from as regards the aesthetics; it would really look cool, even if the weight of the bike didn't come down appreciably. I just wouldn't take the chance after my experience.
DD