Originally Posted by
wrk101
If it is really stuck, cutting it out isn't that bad really, particularly on a stem. Seat post is more painful to cut out.
Realize you CAN put more force on a frame than it can take. I've bent frames trying to gorilla out a stuck stem or seat post. I have made a jig to hold the fork crown (carefully) in my bench vise, then put a long steel bar through the stem clamp (you WILL bend aluminum handlebars). I've gotten several out that way. Kroil for the win, PB Blaster is a joke. I've had panto'd stems where the stem was worth as much as the frame. So cutting it out was not a good option.
As a chemical engineer, I will NEVER recommend lye. First, it is dangerous. Secondly, it will destroy the paint. Forget it.
I have had success with a similar method: fork crown in the vise with hardwood to protect the finish, then, after lots of penetrating oil, use the leverage of the bars to try and get the stem to move (and as Bill advised, don’t use bars you’re fond of). If it doesn’t move with reasonable force, apply more penetrating oil and wait another 24 hours.