Vinegaring Stuck Stem Of 90's Trek
 

Tried to get my stem unstuck all morning. Greased it, hammered it, etc. Wondering if turning my frame upside down and pouring some white vinegar will work with this sort of fork/headset? Thanks in advance!

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Stem looks aluminium. How far have you been able to get it apart. The long bolt out? The wedge loose? Often Pb-Blaster and time will do the trick. That is spray the hell out of it and let it sit for a few days.

Definitely is aluminum! The bolt unscrews (without moving upwards), but I can pull it upwards while the allen wrench is inserted, which makes me think the wedge is also loose? I tried to oil it a good amount this morning, just around the lip where the stem meets the locknut, but no luck.

Don't want to use much more force tbh, already a bit concerned about my headset, but it is a project bike so maybe it was already a bit crunchy.

I'll look into the PB Blaster. Thanks for the tip. Would you still apply it with the frame flipped upside down like this? Or just from every angle I can lol?

Def try some PB Blaster, I have used it with success across a number of applications.

Snug up the bolt for the wedge then unscrew it three or for turns. Take a mallet and give the head of the bolt a good smack. This will ensure the wedge is released and not causing your issue. If your bolt head is countersunk into the stem, then put a punch or nail that fits into the socket of the bolt and bang on that.

Oh I'm only asking this because it's been done by others......... you aren't loosening the big nut thinking that that lets you get the stem out are you?

You might also look at Sheldon Browns list of ways to remove a stuck seat post. https://www.sheldonbrown.com/stuck-seatposts.html I have been tempted to try the caustic soda / lye method to remove the stem in an old Trek steel frame that I have but have not decided that sacrificing the stem is the way to go yet.

All morning? I am into the second year of dripping supposedly magical fluids on the seatpost of a Claud Butler with years of shed time.

On a more practical note, clamping timbers either side of the fork crown with bolts can give safe extra leverage. I then use two closely-spaced street poles to resist the handlebar torque.

ahhh no. was just planning to try to go drip some pb blaster in there lmao. already feeling pretty skeptical about any of this working. might just have to live with that stem.

thanks for the tip tho. definitely sounds like it could help with leverage !

thanks for the list. the ammonia method sounds tempting, but also questionable for aluminum stems. i'm basically tempted to cut it out or live with it. i'm going to go spray a bunch of pb blaster and let it sit for a while. might try ammonia if that doesn't work after a few days. then just have to suck it up probably :\

If all of the methods you try have not worked try the 50/50 mix of automatic transmission fluid and acetone, filled to the point that the steering tube is full when turned upside down. Give it 24 hours and then try to move the stem. I have had good progress with this method. Smiles, MH