Bicycle Mechanics - CAAD 8 Seatpost fitment trouble.

Very confused here, sick of the punishment of a aluminum seatpost in my CAAD 8 so I went out to the garage this morning to change it out. I have 2 other 27.2 carbon posts from other frames so i decided to stick one in. Neither will fit, I mean they go in, but not without A LOT of effort, and I can't get either of them in farther than a couple cm. I slid the carbon wrapped aluminum post back in, it goes in fairly easily, does take a tiny bit of pressure. What is going on here? I cleaned out the seattube before trying, could the carbon posts be slightly swollen from the high humidity here?

your sure your frame isn't 27.0 ?

your sure your frame isn't 27.0 ?

Positive, the post that came out was 27.2. Also that would make it the only 27.0 seattube CAAD8 frame that Cannondale ever made.

anyone have some advice?

vw addict, While I don't buy into the humidity idea, it's still a possibility. Put one of the carbon seatposts into the freezer over night and see how that goes... the reverse of heating a ring gear to fit a carrier.

Brad

only problem is I don't want to it to swell back up and get stuck in the frame.

Positive, the post that came out was 27.2. Also that would make it the only 27.0 seattube CAAD8 frame that Cannondale ever made.

so you've measured both?

my shot-in-the-dark guess is that some of the resin material came off the original seat post (if it is carbon wrapped like mine) through electrolosis and bonded to the inside of the frame.