I am turning to you all in a last ditch appeal for help with an incredibly stubborn stuck stem and fork.
In the past year I have defeated about 5 seriously stuck seatposts and 4 stem/fork tubes, some of which took weeks of soaking to free. But this one, after two months, has be stumped.
So far I have undertaken the following measures:
1. soaked it both sides in Liquid Wrench.
2. removed the bolt and plug from the stem,
3. heated it with boiling water (per Dave Moulton)
4. I have replaced the handlebars with long metal pole to get excellent leverage.
5. I have (carefully, or as carefully as I reasonably can. and I have them locked in at the shoulders so I think it should be solid enough) locked the fork blades in a wooden Workmate bench vise.
6. filled the headtube with diesel fuel for 2 days.
7. frozen it (handily, it is freezing here in Toronto so I just left it outside for a few hours.)
8.I have bashed it hard with a sledge hammer (to break up the bond?), dropouts on concrete, stem protected by a block of wood (I'd rather not trash the stem.)
About 2 months ago, after the liquid wrench drenching and heating (step 3) I got an encouraging CREAK and small bit of play.
then it seemed to seize right up again.
this week, after 2 days of diesel fuel soaking, freezing, bashing, I got another CREAK and a little more play. But then it seized right up Again (I can't figure this out - I would think that if it started to move, it should stay movable... I am guessing that if the surfaces are really rough in there, it could get stuck again in a new position?)
it should be noted that the the frame to this Colnago is already seriously damaged (cracks and holes in the down tube) and so would need serious refurbishment anyway.
But I would like to recover the forks and stem. someone could use them.