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-   -   "New" old bike problems: What the hell is wrong with this quill stem? (https://www.bikeforums.net/bicycle-mechanics/818446-new-old-bike-problems-what-hell-wrong-quill-stem.html)

Reeses 05-15-12 10:24 PM

"New" old bike problems: What the hell is wrong with this quill stem?
 
**Stem problem solved!**

Hi, I need some insight into this:
http://farm9.staticflickr.com/8005/7...a55bc7bb_b.jpg
http://farm8.staticflickr.com/7102/7...0b4777f8_b.jpg

The stem bolt is immovable. I've looked into loosening stem bolts but why is it protruding from the stem?

FBinNY 05-15-12 10:39 PM

Looking at the improvised headset locknut, I wouldn't be surprised if the stem bolt wasn't original and was simply forced into the stem. When you say immovable, as I correct in assuming that you mean you can't turn it?

If so, flip the bike over and soak the wedge with Kroil, or PB Blaster or whatever penetrating oil is sold by your local hardware store. That may loosen up any rust holding it frozen and allow you to turn it, then drive the wedge down and free stem.

While you're waiting for the oil to do it's stick on the bolt, spray some around the stem and let it wick down into the fork in case there's corrosion there also. That will save you another 6 hours waiting at the next step.

BTW- even if it won't turn, maybe it's already backed off, so you might give it a shot at hammering it in, and maybe freeing the wedge. That will free the stem, and you can deal with the frozen threads later on.

relyt 05-15-12 10:39 PM

It probably isn't the bolt that originally came with the stem, and it doesn't fit flush.

Jeff Wills 05-15-12 10:40 PM

OK- the bike looks like a collection of random parts. (For instance, the headset locknut looks really out of place on that fork.) I would guess that someone's replaced a standard-head bolt with a hex-head (aka Allen-head) type. If it holds without slipping, don't mess with it.

OTOH- are you trying to remove the stem? If you've unscrewed the bolt a couple turns, give it a tap with a hammer. There's a wedge at the bottom of the stem that won't move unless you break it loose.

Reeses 05-15-12 10:52 PM


Originally Posted by Jeff Wills (Post 14229099)
OTOH- are you trying to remove the stem? If you've unscrewed the bolt a couple turns, give it a tap with a hammer. There's a wedge at the bottom of the stem that won't move unless you break it loose.

The bolt itself won't budge.


Originally Posted by FBinNY (Post 14229096)
Looking at the improvised headset locknut, I wouldn't be surprised if the stem bolt wasn't original and was simply forced into the stem. When you say immovable, as I correct in assuming that you mean you can't turn it?

If so, flip the bike over and soak the wedge with Kroil, or PB Blaster or whatever penetrating oil is sold by your local hardware store. That may loosen up any rust holding it frozen and allow you to turn it, then drive the wedge down and free stem.

While you're waiting for the oil to do it's stick on the bolt, spray some around the stem and let it wick down into the fork in case there's corrosion there also. That will save you another 6 hours waiting at the next step.

BTW- even if it won't turn, maybe it's already backed off, so you might give it a shot at hammering it in, and maybe freeing the wedge. That will free the stem, and you can deal with the frozen threads later on.

Yeah I mean I can't turn the stem bolt. I'm trying to remove it so I can replace the fork. How much do I back out the stem bolt before I hammer it down?

FBinNY 05-15-12 11:14 PM


Originally Posted by Reeses (Post 14229120)
The bolt itself won't budge.

...Yeah I mean I can't turn the stem bolt. I'm trying to remove it so I can replace the fork. How much do I back out the stem bolt before I hammer it down?

If you can't turn the bolt, how far to back it out is a moot question. But if the Kroil get's you to where it can turn, you back it out about 1/8" then tap it down to free the wedge. As I said, it might be frozen backed out already, so you can give give the hammer a shot now. Put a hex key in the socket, and drive it that way so you don't hammer the hex closed.

If all else fails, and you don't want the stem anyway, you can saw it straight across then drive the remainder of the bolt down. If you go hat route, be sure to make the cut high so you have something to grab onto and twist, to remove the stem.

Jeff Wills 05-16-12 06:23 PM


Originally Posted by Reeses (Post 14229120)
The bolt itself won't budge.

Yeah I mean I can't turn the stem bolt. I'm trying to remove it so I can replace the fork. How much do I back out the stem bolt before I hammer it down?

Ouch. Considering the headset locknut is almost made for moisture infiltration and that the bike appears to be a kitbashed mongrel, I bet it's a mass of corrosion in there.

If you're going to replace the fork, replace the stem while you're at it. Off with its head!

Reeses 05-16-12 08:46 PM


Originally Posted by Jeff Wills (Post 14233289)
Ouch. Considering the headset locknut is almost made for moisture infiltration and that the bike appears to be a kitbashed mongrel, I bet it's a mass of corrosion in there.

If you're going to replace the fork, replace the stem while you're at it. Off with its head!

Would a bike shop be able to do this for me?

Jseis 05-16-12 09:04 PM

I'd be inclined to try a very tight yellow flame to the center (only) of the Allen bolt for maybe 30-40 seconds, then flip the bike and drench in a penetrating fluid (after during off flame!). Nowhere near red hot, just 500 or so degrees to get the heat down the bolt. Also tap lightly after heating, several swift taps though not hard. Do this several times over a week. Aluminum is a great heat sink and I doubt the stem will be bothered but you can wrap it and the head tube in ice. Temperature differentials can often free parts. The absolute worst corrission situation is high carbon steel threads and aluminum (weren't those head tube slip jam fittings aluminum? Can't remember) and you might be there. Gentle force might work over time given focused heat, light shock, penetrating fluids.

IthaDan 05-16-12 09:15 PM

Get some torque on that bolt-

http://i.imgur.com/LMyzQ.jpg

http://i.imgur.com/2QWJu.png

http://i.imgur.com/2hiks.jpg
(find the longest black pipe nipple in 1/2" that home depot has)

Then whack the head of the bolt with a hammer to free up the wedge. (Optional)- If you can get the bolt spinning, and can take it all the way out, you might want to remove the locknut and then put the stem back in for leverage on the wedge. I say this because sometimes the lip on the locknut will get in the way of getting a gunked up wedge out easily.

Oh, and PB blaster/liquid wrench/deep creep. Lots and lots.

And the Phrase "kitbashed mongrel" is inspired. :thumb:

Jeff Wills 05-16-12 11:14 PM


Originally Posted by Reeses (Post 14233886)
Would a bike shop be able to do this for me?

Any bike shop with a hacksaw... :)

Reeses 05-18-12 10:15 AM


Originally Posted by IthaDan (Post 14233993)
Get some torque on that bolt

Well that worked. Turns out the wedge wasnt put in straight... Ive no idea how the previous owner tightened itdown so much.

I took the fork out ok but can someone fill me in on the headset? What type do i need if the fork is 1" threaded?

DannoXYZ 05-18-12 01:35 PM

Read up on 1" headset specs here: Park Tool - Headset Standards (table at bottom). You'll want to verify:

1. headtube ID
2. head cups OD
3. steerer ID
4. stem quill OD

These come in varying dimensions and getting the wrong sized part can make re-assembly a bugger. I suspect that the giant nut doesn't have the proper thread-pitch to fit over the steerer-tube, so the threads on the steerer are most likely damaged. A the very least, you may need to bring it in and have the threads re-cut & chased.

DCB0 05-18-12 02:31 PM

I cannot see the pic on my current internet connection, but I am betting it is the style of bike that when I see them I assume they are stolen.

Jeff Wills 05-18-12 07:00 PM


Originally Posted by Reeses (Post 14240759)
Well that worked. Turns out the wedge wasnt put in straight... Ive no idea how the previous owner tightened itdown so much.

I took the fork out ok but can someone fill me in on the headset? What type do i need if the fork is 1" threaded?

As I said before- it's a collection of mismatched parts. It looks like made-in-Japan Schwinn headset parts, but with a gigantic Wald lock nut. All of that is covered in spray paint.

As Danno said, if you need replacements, you'll need to measure the old parts and hope that someone hasn't tried to make the incorrect parts work.

Reeses 05-18-12 07:29 PM


Originally Posted by DannoXYZ (Post 14241793)
A the very least, you may need to bring it in and have the threads re-cut & chased.

Thanks for the warning.

Originally Posted by Jeff Wills (Post 14242995)
As I said before- it's a collection of mismatched parts. It looks like made-in-Japan Schwinn headset parts, but with a gigantic Wald lock nut. All of that is covered in spray paint.

I think the stem bolt was the original stem bolt, cuz there isn't a recessed area for the stem bolt to go in.

wrk101 05-18-12 07:42 PM


Originally Posted by Reeses (Post 14243106)


I think the stem bolt was the original stem bolt, cuz there isn't a recessed area for the stem bolt to go in.

Nope. Round head with allen socket = meant to go into a recessed area on the stem. No recessed area = should have a hex head bolt on it. Someone swapped it out.

storckm 05-18-12 07:56 PM

I've had something that looks similar happen occasionally, where the wedge doesn't come loose. I find that a few whacks with a mallet can help loosen things up. If that isn't good enough, you could try tapping with a hammer. It's always worked for me, and it doesn't involve ruining parts.

DannoXYZ 05-19-12 03:55 AM


Originally Posted by Reeses (Post 14243106)
I think the stem bolt was the original stem bolt, cuz there isn't a recessed area for the stem bolt to go in.

Original stem-bolt was a thin hex-head bolt.

Kimmo 05-19-12 04:59 AM

Dunno why, but IMO that massive locknut looks kinda cool.

Reeses 05-19-12 10:02 PM


Originally Posted by Kimmo (Post 14243963)
Dunno why, but IMO that massive locknut looks kinda cool.

Lol yeah but it doesn't seem to function as intended ...

Originally Posted by Jeff Wills (Post 14242995)
It looks like made-in-Japan Schwinn headset parts, but with a gigantic Wald lock nut.

I have a few questions regarding that giant lock nut. It seems if I don't tighten it down, the fork is a little loose in the headset, meaning it moves back and forth. But if I tighten it, the fork is tight but it gets progressively harder to steer.

Jeff Wills 05-19-12 10:38 PM


Originally Posted by Reeses (Post 14246349)
I have a few questions regarding that giant lock nut. It seems if I don't tighten it down, the fork is a little loose in the headset, meaning it moves back and forth. But if I tighten it, the fork is tight but it gets progressively harder to steer.

That's tough to diagnose, even with the bike on the stand. It could be any number of things: worn-out headset, bent steerer tube, incorrectly installed headset cups, ovaled head tube, wrong number of ball bearings... it goes on and on. Bikes are incredibly simple devices, but one small goof can throw everything off.

LesterOfPuppets 05-19-12 10:50 PM


Originally Posted by Reeses (Post 14246349)
Lol yeah but it doesn't seem to function as intended ...

I have a few questions regarding that giant lock nut. It seems if I don't tighten it down, the fork is a little loose in the headset, meaning it moves back and forth. But if I tighten it, the fork is tight but it gets progressively harder to steer.

That's probably because there's no keyed washer under it. To not overtighten bearing you need to adjust the headset cone, then get a keyed washer under the locknut or hold the upper headset cone in place with some big ol' Channel Locks or a pipe wrench or whathaveyou while you crank down the locknut.

Jeff Wills 05-19-12 10:55 PM


Originally Posted by LesterOfPuppets (Post 14246451)
That's probably because there's no keyed washer under it. To not overtighten bearing you need to adjust the headset cone, then get a keyed washer under the locknut or hold the upper headset cone in place with some big ol' Channel Locks or a pipe wrench or whathaveyou while you crank down the locknut.

Looking back at the original photo, this is probably the issue. I shouldn't post when I'm sneezing my brains out (mowed the lawn today).

Reeses 05-19-12 11:16 PM


Originally Posted by LesterOfPuppets (Post 14246451)
That's probably because there's no keyed washer under it. To not overtighten bearing you need to adjust the headset cone, then get a keyed washer under the locknut or hold the upper headset cone in place with some big ol' Channel Locks or a pipe wrench or whathaveyou while you crank down the locknut.

There was a keyed washer, just not under the locknut. He put the keyed washer between the ball bearings and adjustable race. I looked on Sheldon Brown's site to get the order right. It's ok now but I found out I dont have a seal between the crown race and the ball bearings- how much of a problem will that cause?


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