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Old 12-05-10, 10:41 PM   #1
whatok
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Fuzed stem?

Hi guys, first post, lurked a while.

Any ideas what the hell is going on here? It won't budge, yet i can't see anything fixing it, and it looks as if the hole where the bolt should have been is filed/cut down.





Maybe it became fused but the bolt still came out? I don't know much atall about it, but i'm pretty sure theres supposed to be some kind of bolt, no?!


Thanks for any help!

Last edited by whatok; 12-05-10 at 10:55 PM.
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Old 12-05-10, 10:48 PM   #2
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The stem is seized in place and the stem bolt has been removed... this is not safe to ride as the stem could release itself at a very inopportune moment.

You need to find a stem bolt that will thread into the pinch nut that is probably jammed in the bottom of the stem and give that a tap with a hammer to see if that releases the stem... a lot of people don't know how a quill stem releases and will remove the stem bolt thinking this is all that is required.

Or they will unscrew the top bearing nuts...

If tapping the pinch bolt does not yield a favorable result, you may have to treat the stem with some penetrating fluid as well and see if that causes it to release.
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Old 12-05-10, 10:52 PM   #3
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Yes, there's usually a bolt which draws a wedge up to secure the stem to the inside of the fork's steering column. I assume you're not the original owner, so there's no telling what the prior owner did.

It's possible that the stem is bound by corrosion. It's also possible that it was pushed in so far that it wedged on the larger OD common at the tops of stems, or the smaller ID at the bottom 2-3 inches of steering columns.

Try removing the wheel and looking up from the bottom of the fork, and if there's no wedge you might be able to push the stem up with a hammer and punch.
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Old 12-05-10, 11:02 PM   #4
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there doesn't appear to be any kind of wedge left, you can see in the 3rd picture that there's nothing really in there. I will take another look tomorrow but if theres nothing in there i will probably have to burn it out like a seatpost, no?
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Old 12-05-10, 11:12 PM   #5
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Quote:
Originally Posted by whatok View Post
there doesn't appear to be any kind of wedge left, you can see in the 3rd picture that there's nothing really in there. I will take another look tomorrow but if theres nothing in there i will probably have to burn it out like a seatpost, no?
No, though possible, that's the hard way and likely to cause complications.

As I said, first look up from the bottom of the steerer, with the wheel out of the way, and odds are if the wedge is truly missing you can push it out from the bottom.

BTW- you can't push it up from the bottom if the wedge is there, because that will drive the wedge tighter.
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Old 12-05-10, 11:13 PM   #6
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How would you see a wedge in the 3rd picture? The bolt hole goes through it as well. You would have to look up from the bottom of the fork to see the wedge.
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Old 12-05-10, 11:52 PM   #7
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the wedges are at the bottom.
the one on the left is more common than the one on the right.
http://upload.wikimedia.org/wikipedi...uill_stems.JPG
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Old 12-06-10, 12:16 AM   #8
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thanks for being so helpful guys.

I will give it a look tomorrow and report back. The frame also has a completely seized seatpost so it makes sense that the stem is likewise.

Unfortunate because the frame is really charming but might not be worth all this hassle.
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Old 12-06-10, 05:00 AM   #9
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Ok, i have checked in daylight.
There is a totally misshapen wedge at the bottom of the headtube, resting on the brake bolt but fused to the walls of the tube at an angle. I reckon if i hit it with a hammer>screwdriver i could dislodge it/break it up.

So after that i would need to extract this stem.

My plan is:

Cut stem to 1" above headset. (Casualty of war)
Remove top headset assembly. (I will probably need to replace this anyway as it's quite gritty).
Give the stem a few big whacks with a mallet, bracing the fork crown on a wooden anchor.

Hope that this dislodges the stem, and the fork/hacked stem come freely out of the bottom of the headtube.

Then Dip the head of the fork in caustic soda, and fizz away the remains of the stem.

What do you reckon? Or have i got it all wrong?

If it doesn't dislodge with the mallet, how do i go about applying caustic while still in the headtube, without getting any on the forks (chrome)? I don't mind the paint on the frame since it's going to be refinished, but i'd like to keep the forks as is.

Thanks guys!
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Old 12-06-10, 12:03 PM   #10
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Ok, i have checked in daylight.
There is a totally misshapen wedge at the bottom of the headtube, resting on the brake bolt but fused to the walls of the tube at an angle. I reckon if i hit it with a hammer>screwdriver i could dislodge it/break it up.

So after that i would need to extract this stem.

My plan is:

Cut stem to 1" above headset. (Casualty of war)
Remove top headset assembly. (I will probably need to replace this anyway as it's quite gritty).
Give the stem a few big whacks with a mallet, bracing the fork crown on a wooden anchor.

Hope that this dislodges the stem, and the fork/hacked stem come freely out of the bottom of the headtube.

Then Dip the head of the fork in caustic soda, and fizz away the remains of the stem.

What do you reckon? Or have i got it all wrong?

If it doesn't dislodge with the mallet, how do i go about applying caustic while still in the headtube, without getting any on the forks (chrome)? I don't mind the paint on the frame since it's going to be refinished, but i'd like to keep the forks as is.

Thanks guys!
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Old 12-06-10, 12:33 PM   #11
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Liquid Wrench or PB Blaster may help loosen things up.
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Old 12-06-10, 01:59 PM   #12
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Don't cut the stem. If you do there's nothing decent to grab and twist with. I'd go with the ammonia soak as suggested on Sheldon's website and in a lot of other threads around here for freeing up stuck aluminium seat posts. Seal off the center hole with some sort of tape and pout the ammonia in from the bottom of the crown. You'll have the bike upside down with the BB removed anyway to allow the same on the seat post so do both at the same time.
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Old 12-07-10, 05:00 AM   #13
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Well this is a little embarrassing.

Before you guys posted, I decided to go ahead and hack the stem off.
So now i have a kilo of caustic ready to go on a fork with bout 4 inches of stem stuck inside it.

I will bung the crown with some putty and a plastic bag/tape, fill the stem with hot solution and wait.

Meanwhile, i would like to start on the fuzed post;

Uploaded with ImageShack.us

This has been attacked by a couple of bike shops, both admitted defeat. The frame is quite delicate and so it wasn't worth applying any more torque.

I will use the same method of caustic, poured in through the bb shell.
I'll keep the thread updated with pictures of the whole process.
Cheers!
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Old 12-07-10, 08:02 AM   #14
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Good luck.
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