Tenacious stem
#1
Tenacious stem
Hi
I have a tenacious stem which refuse to leave its hole.
It moves, up and down, turns right or left, but refuses to come out.
I tried gentle, I tried some force.
Nothing.
Any ideas?
Thanks
I have a tenacious stem which refuse to leave its hole.
It moves, up and down, turns right or left, but refuses to come out.
I tried gentle, I tried some force.
Nothing.
Any ideas?
Thanks
#3
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From: Berkeley, CA
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How far up does it go? Could it be the wedge is catching on the headset locknut? Maybe tighten the stem bolt a little (but not too tight to move) so the wedge nut stays in line with stem shaft, or try unscrewing the headset locknut?
#4
It's an extra long stem. It goes all the way in. The nut must be 40cm long. Most of it comes out.
I've removed the wedge nut. No change.
I've removed the headset locknut. Removed all bearings for access. No change.
It could be as you said the wedge catching on something but can't see what.
I've removed the wedge nut. No change.
I've removed the headset locknut. Removed all bearings for access. No change.
It could be as you said the wedge catching on something but can't see what.
Last edited by ConnoisseurEqua; 09-19-22 at 08:29 PM.
#5
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Joined: Sep 2005
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From: Oakland, CA
Bikes: '82 Univega Competizione, '72 Motobecane Grand Record, '83 Mercian KOM Touring, '85 Univega Alpina Uno, '76 Eisentraut Limited
Could you post a couple of pics? I’m stumped. Maybe head badge rivets?
#8
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Bikes: too many sparkly Italians, some sweet Americans and a couple interesting Japanese
It's an extra long stem. It goes all the way in. The nut must be 40cm long. Most of it comes out.
I've removed the wedge nut. No change.
I've removed the headset locknut. Removed all bearings for access. No change.
It could be as you said the wedge catching on something but can't see what.
I've removed the wedge nut. No change.
I've removed the headset locknut. Removed all bearings for access. No change.
It could be as you said the wedge catching on something but can't see what.
#9
Senior Member

Joined: Sep 2005
Posts: 3,486
Likes: 1,552
From: Oakland, CA
Bikes: '82 Univega Competizione, '72 Motobecane Grand Record, '83 Mercian KOM Touring, '85 Univega Alpina Uno, '76 Eisentraut Limited
#14
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Joined: Oct 2005
Posts: 1,914
Likes: 449
From: Upper Left, USA
#15
Senior Member

Joined: Sep 2005
Posts: 3,486
Likes: 1,552
From: Oakland, CA
Bikes: '82 Univega Competizione, '72 Motobecane Grand Record, '83 Mercian KOM Touring, '85 Univega Alpina Uno, '76 Eisentraut Limited
It looks like this type of Humpert stem (taller than the one in the pic I’m posting, which comes from evilbay). Looks like a traditional wedge, no surprises. Yes, if you have not disconnected the cables yet, I agree that this is likely the cause, since you’re able to get all kinds of movement.
#19
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Joined: Oct 2005
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From: Upper Left, USA
You are holding back some details! Have you already used penetrant? It looks like that rust is wet with something. When you thread the bolt in, are you able to tell if the wedge is loose? If not, smack the bolt with a hammer (with some wood inbetween if you want to keep the bolt looking nice) to get it fully loose. It might be stuck to the bottom of the stem just enough to be keeping the stem locked in the steerer.
#21
I applied WD-40 on both side. The rust is the WD-40 with some rust dust.
I will try to bold it in again and use my rubber mallet. But I don't recall hearing the bottom of the stem moving freely.
I will try to bold it in again and use my rubber mallet. But I don't recall hearing the bottom of the stem moving freely.
#24
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Joined: May 2012
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From: Point Reyes Station, California
Bikes: Indeed!
...When you thread the bolt in, are you able to tell if the wedge is loose? If not, smack the bolt with a hammer (with some wood inbetween if you want to keep the bolt looking nice) to get it fully loose. It might be stuck to the bottom of the stem just enough to be keeping the stem locked in the steerer.
At this point you should thread the bolt back into the wedge a few turns and then smack it with a hammer to loosen the wedge. Your rubber mallet may not work, but a dead-blow hammer or a steel hammer should do the job. As mentioned above you can protect the finish on the bolt head with a piece of lumber between the hammer and the bolt.
Brent
#25
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Joined: Jan 2004
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From: Madison, WI USA
Wait, I thought the wedge was already out of the equation, based on post # 4. But now it's sounding more like a garden-variety broken stem. If the wedge has NOT been removed (well, "released" would be more accurate, I suppose), and is still engaged with the bolt, AND the stem proper is broken in two pieces below what we can see, you'll experience just what you're describing. The bottom bit of the broken stem will "affiliate" with the wedge and not want to turn or come out, even while you're lifting and wrestling with the rest of the stem. It's happened to me, but only with aluminum stems, never with steel. That said, never say never....
Try this - Pull upward gently on the stem, and continue turning the bolt counter-clockwise. That upward pressure should (well, might) hold the broken bit / wedge from rotating, and you might eventually get the bolt to unthread entirely from the wedge, releasing it, and the busted bit of stem, to fall into the steerer. Then the main part of the stem should just pull out, and you should be able to flip the bike over and the rest will drop out.
If that's not it, you might also shed some light on your situation by looking from underneath; you may even want to remove the brake bolt, just for a better visual sense of what's going on.
Try this - Pull upward gently on the stem, and continue turning the bolt counter-clockwise. That upward pressure should (well, might) hold the broken bit / wedge from rotating, and you might eventually get the bolt to unthread entirely from the wedge, releasing it, and the busted bit of stem, to fall into the steerer. Then the main part of the stem should just pull out, and you should be able to flip the bike over and the rest will drop out.
If that's not it, you might also shed some light on your situation by looking from underneath; you may even want to remove the brake bolt, just for a better visual sense of what's going on.







