I started a thread a while back about trying to get my stem out:
After working on it some more, I've decided I have no idea what I'm doing. So I'm back for more help. It's a Modolo Race quill stem. I thought it had a normal wedge in it, but now I think not. My usual technique for stem extraction is to back off the stem bolt and whack it or the T-wrench with a hammer, driving the bolt and wedge down. I tell if this worked by backing out the stem bolt further and seeing if the bold head is coming up as I unscrew. It seemed on this stem as though the wedge wasn't moving. So I turned the bike over, squirted a large quantity of Kroil into the hole in the fork crown, and left it for a week.
I tried it again today, no progress, so I pulled off the front brake, screwed the stem bolt into what I thought was the bottom of the wedge, and tried a slide hammer puller. Nothing. Then I got to looking closer up the hole. Now I see that the stem bolt screws into a hole threaded into a solid horizontal cylinder that's inside what I think is the stem. This cylinder turns easily on its horizontal axis, so that it's tricky to get the stem bolt threaded into it.
So looking up the hole in the fork crown, I see what I think is the end of the stem. It's a cylinder with maybe 3 mm wall thickness that touches the inside of the steer tube all the way around. Then about 6 mm from the bottom of what I think is the stem I see this solid, rotatable cylinder with the stem bolt hole drilled in it, inside of what I think is the stem. What is going on here? How does this work? What am I looking at?
The stem is still immovable by normal means. I could loosely clamp the carbon fork legs in a large wood jawed vice that I have, up near the crown, and then put a 24" crescent wrench on the stem and see what happened, but I'm nervous about doing this for fear of ruining the fork.
When I pulled the stem bolt out, I could see a residue of anti-seize on it quite clearly, so I'm pretty sure I put anti-seize on the whole assembly when I installed it years ago. But I've forgotten how this stem works!
This is my personal bike. I am not a pro bike wrench, duh. And I'm sorry about ending the title sentence with a preposition.