sloar 

I really had mixed feeling about this. My newly acquired bike that I paid more than any other bike had a severely stuck stem. I thought about just leaving it because it was the right heighth. But the headset needed serviced really bad. I hated doing it but stems can be replaced, and in the end I’ll feel better about it.

wrk101

This is usually the right approach. I did have a panto'd stem once that I kind of had to save. Otherwise, cutting them out is my preferred choice.

I always check them and post on any bike I am thinking about buying. Even when they are stuck, I still will buy at the appropriate discount. Basically I put a value on the components, and the value of the frame is my reward when I get it out.

bikemig 

How did you get the stem out? I have a stuck stem in a 70s Raleigh Competition I'm having mixed feelings about as well. I bought it to fix up for my nephew. A bike with huret drop outs is just about perfect for a one speed conversion. The stem is at the right height and my guess is that he'll find a way to muck up the bike or get it stolen (he lives in a large city) long before the headset gives out. . . .

Reynolds 531 

Next time around, you can easily service the headset without removing the stem.

You can even replace ball bearings one at a time, even rotate cups to a fresh position

If for some reason, actual parts need replacing, you can always remove a stuck stem with enough cleverness and patience. (plus some C+V forum lessons in chemistry)

fender1

Ouch! Always disappointing when something like this happens. That said, I would have done the same thing. I hate to leave things half done. Situations like this just get worse if left alone.

I replaced the bars and stem on my 72' chrome Paramount ( Stem was the wrong size and I don't ride vintage handlebars) I used this Nitto stem:

https://www.somafabshop.com/shop/nit...attr=2593,4038

and some Nitto Noodle handlebars.

Good luck!

Mr. 66

One way is to clamp the fork in a big vise, and manhandle with the bars in place.

Another is to J-clamp the fork crown while straddling the downtube, then manhandle the handlebars. I don't have a picture of that.

Both need a liberal use of PB Blaster.

sloar 

I cut the stem off with around an inch sticking out the top. Used a hacksaw blade and cut slits on the inside the fork tube. Once I got a through cut on both sides I squeezed the top with pliers and twisted it out. I tried brute force first but I didn’t want to tweak the fork blades.

bulgie 

Save the bolts from that stem. Apologies if that's too obvious to mention. Offer them here if you don't have a use for them, someone here needs them.

repechage

Depends on the tools at hand.
a disappointment to sacrifice an earlier model Cinelli stem, but so it goes.

I did buy a frame and fork once that had the stem already cut off, bought cheap due to that.
took 5 minutes with a securely mounted bench vise and Kroil application the day before.

don't spoil it, Kroil it.

albrt 

Warning - some old alloy stems have a very narrow cavity in the middle, not enough to insert a hacksaw blade or get any leverage for jail-breaking.

dddd

I usually heat the stem with a propane torch, which expands the length of the aluminum stem quill considerably more than the steel steer tube, helping to crack the fierce bond between stem quill and steerer.

I then let the stem cool, at some point applying a penetrating oil while the stem is still cooling. When fully cooled (perhaps even further using ice) the stem is found to be much easier to twist out, based on my limited experience dealing with what seem like "really" stuck stems.

There is some limit as to how much heat that you want to apply to an alloy stem, but 300-400F will be thoroughly cooking any old oils (i.e. pretty hot) while being harmless to the frame, fork, stem and headset.
I loosen the handlebar clamp and might try to insert some insulating shim between bar and stem just to reduce the heat-sinking.
The transfer of heat to the painted head tube seemed minimal when I've done this, the effective heat path through the ball bearings being minimal.

jasoninohio

This vise setup deserves it's own post somewhere

john903

Now that's a vice! What is a good way to protect the fork from denting or twisted?

sloar 

I was more concerned about damaging the frame or fork. I don’t mind replacing the stem.

bulgie 

You call that a vise? This is a vise:



From Fireball Tool. One of the things he's used it for is to crush lesser vises to see where they break.

The screw (on the right), which is substantial, is mostly used to set the beginning gap in the jaws, then the real clamping force kicks in when you pump up that hydraulic cylinder on the left.

I dig the pinstriping!

79pmooney

It's solidly bolted to that post. Pretty sure it claims ownership.

icemilkcoffee 

You can then hit it with a freeze spray, which will shrink the aluminum quickly and separate it from the steel tube.

dddd

That's the idea, exactly.

The chilling will also slightly reduce the aluminum quill's diameter, which can only help.

Believe it or not, the compressed layer of corrosion means that it still resists turning after it first breaks loose as you twist it, but the main battle is over as the penetrant is then finally able to creep in.