Joined: Jan 2008
Posts: 23,642
Likes: 1,106
From: Mans of NC & SW UT Desert
Bikes: 86 Katakura Silk, 87 Prologue X2, 88 Cimarron LE, 1975 Sekai 4000 Professional, 73 Paramount, plus more
Head to a bike shop before you get one terminally stuck, or damage the bike. Never, ever, force a seat post. I just finished removing the remnants of a 27.3mm seat post, that had sheared off inside the seat tube (bike was sized for a 26.8mm seat post).
+1 I use a brake hone on older steel bikes, as I tend to find burrs and other defects in the seat tube.