well I guess we’ve all had a seatpost that’s got stuck in the frame at some point or another, well I’ve now got a seat post that won’t go in the frame. My giant xtc carbon alloy frame has been hanging up in the shed for pretty much three years unused. I dismantled it to build another bike but since accumulating some spare parts I decided to build it back up again. Thing is, the seatpost that I’ve had with the bike since 2009 no longer fits into the seat tube. It goes in about 4ins and then goes tight and stops. I then have to put my foot on the frame to hold it down whilst I twist it back out again. There’s definitely nothing in the way to stop it going down, I’ve had a look with a torch and screwdrivers to check, I can see it’s clear down to the BB. The post is a 30.9mm (I think) alloy and still has the marks on it from where it used to go in, and when last in use it was regularly removed to fit a mudguard when needed. The top half of the seat tube is carbon btw. so what could possibly have happened in the last three years to stop it going back in properly now?