seatposter

Seems my Bontrager aluminum seatpost has become permanently fused to the seat tube on my Trek 5200 OCLV frame. I've read that this could be a galvanic reaction to lubricant on the seatpost and the frame. Luckily it is at the correct ride height. But I need to get the sucker out. Any suggestions? My local Trek dealer wrench suggest spraying Liquid Wrench into the frame via one of the water bottle mounts and be patient. Stated no damage would occur. But this hasn't worked.

CampyGuy

Ammonia should do the trick. It somehow reacts to the aluminum oxidation and frees it up.

seely

I'm not sure how ammonia is on carbon, so I'm not 100% sure I'd go that route. Honestly, I have no suggestions, just a cautionary warning against using something as harsh as ammonia.

CampyGuy

Oh, I didn't realize it was a carbon frame. In that case I don't know what the best way to get it out is. Sheldon Brown has an article on his website about removing stubborn seatposts.

well biked

The first thing I'd try is installing an old saddle you don't care about on the post, and hit the nose of the old saddle (first one side, then the other) with a hammer a few times. I realize seatposts can get stuck so badly that this method won't work, but it's where I would start. And because the frame is carbon, I wouldn't use the hammer with the same vigor as I would if it were a steel or aluminum frame-

Ophidian

Here's a link that will help.

https://www.velonews.com/tech/report/...s/11799.0.html