Originally Posted by
CliftonGK1
Had to do this with an '88 Trek 400 I salvaged from a dumpster around this time last year. Post was stuck solid and not moving; it was hard to believe it was the right size post to begin with... felt more like someone had just hammered a 27.2 into a 27.0 with how bad it was stuck. Many applications of WD40 and Liquid Wrench, plus generous brute force finally got the darned thing out.
I have an '83 Trek 400 as my rain/beater bike and it does indeed take a 27.2 seatpost. However both the original owner (I bought it used in '98) and I kept the OEM seatpost adequately greased so it's never needed that kind of abuse.