Threaded headset adjustment to realign a quill stem

Bobbinogs

Can anyone help me realign a quill stem? It doesn't have to move by much (probably a mm or 2) but I cannot seem to get the stem to move to align the bars with the front wheel. I figured that I shouldn't need to touch the headset to start with so I just loosened the stem bolt so that it was ridiculously loose and then tried wiggling the stem but it wouldn't budge. Next step was thinking that maybe I did need to backoff the headset a tad first, so I backed off the locknut/bearing adjustment on the headset by a good few turns and then loosened the stem locking bolt...but the stem still won't move.

I have reassembled taking care to ensure the headset is about right (no wiggle but good smooth movement) but the stem is still out by a couple of mm (bike took a knock from a car a few weeks ago and I suspect this is why it is slightly out now).

Thanks in advance.

mercia_man

Loosen stem bolt and then tap stem top with rubber mallet to free it. You can then realign it before tightening again. A bit of grease on stem/steerer interface will help prevent it from seizing again. But don't use too much or you may not be able to secure stem tightly enough. Adjusting a threaded headset will have no effect on the stem.

Bobbinogs

Ah yes, I think i see what you are saying. By tapping the bolt, the locking nut attached to it inside the headtube will drop down a tad and free off? Good idea. Thanks.

mercia_man

Yeah, that's it. If tapping with rubber mallet doesn't free it, try a bit of Plus Gas or similar down the outside of the stem where it goes into the steerer, leave a while and tap again.

Bobbinogs

Well, good news and bad news. The stem bolt/locking nut is now nice and free (the tap on top of the loosened bolt worked a treat). Unfortunately, there is no moving the stem, even with the bolt/locking nut slack. I removed the headset locking nut and dribbled some Plusgas down the stem/head tube a couple of times, left for a while and then tried to move the bars sideways as hard as my puny T-Rex frame could...no joy. I have a feeling this could be an LBS job soonish. I don't need to move the bars that much but I figure just ignoring a frozen stem is only going to let it get worse.

ugo.santalucia

the headset has nothing to do with the quill... with a tight headset you should still be able to adjust the quill. Your problem, I believe is that you have an expander type quill, rather than a wedge type. The expader type can get stuck even when you undo the bolt. The only way to free them when that happens it to remove the top bolt, insert a tiny rod of some sort (could just be a longer bolt) and whack it from the top so that the the expander cone drops at the bottom... you can then recover it by removing the front brake caliper... bit of a palaver, but I see no other way

The Rookie

The steerer comes right through the headset, you do not need to touch the headset AT ALL. Putting plusgas down the outside of the steerer where you did will not move the quill stem which is inside the steerer.

You'll now need to regrease the headset where the plusgas has washed it out!

Face the front of the bike, trap the front wheel between your legs and turn the bars, don't be afraid to apply some force!

mercia_man

That's a shame. I'm not sure from your description whether you have a stem, such as Cinelli, with splits on the bottom end which are pressed out against the steerer by a long expander bolt attached to a cone-shaped wedge nut which moves up and down the inside of the stem tube. Or whether you have a triangular wedge nut which moves up the expander bolt screw directly onto the insides of the steerer.

Here's a suggestion from Richard's Bike Book. If you have the Cinelli type, is the cone-shaped wedge stuck in place and you just have the long expander bolt free? If that is the case, remove the bolt completely and find a rod or bolt or maybe a screwdriver which will fit inside the stem and touch the seized cone-shaped wedge nut while still protruding an inch or two above the stem. Use a hammer to lightly tap the bolt or rod, working the end around the edges of the wedge nut. Work firmly but gently. Too hard a blow will jam the whole thing. When the seized nut comes free from the stem, turn bike upside down and shake out the wedge nut.

EDIT: Just seen ugo has recommended the same thing.

As The Rookie says, don't be afraid to use force when trying to twist stem free.

Of course, it may simply be that your stem has not been removed and greased for years and has seized solid against the inside of the steerer. In which case, LBS is your best bet.

mercia_man

Here's some useful advice, including the use of boiling water. http://davesbikeblog.squarespace.com/bl ... -stem.html

Bobbinogs

OK, thanks for all the suggestions. The stem is a Cinelli which is fitted to a 653 Reynolds frame. Hence, it does have the cone nut on the stem bolt (I checked on some similar stems I have). The cone is moving freely now (attached to the stem bolt) but the stem is not budging. There was some mild corrosion around the stem where it goes into the frame (under the headset locking nut) and I figure that it is the stem that has become stuck as it has been ages since I changed it and regreased. Ho hum. I will have a look at the blog (thanks MM) and see if I fancy it. I am a little hesitant about trying too much in case I damage the Tifosi headset (or front wheel, which is new) either by force or various freeing chemicals, etc.

jermas

Try turning the bike upside down and spray plusgas down the steerer hole at top of the forks. This way the plusgas should reach where it's needed better. If things still don't loosen, you could try using a homebrew mix of 50% ATF fluid dex ii(Halfords) and 50% acetone (thinners) mixed. Replace the quill bolt and fill the steerer tube with the mix and leave. Protect paint work from spills, or use white spirit in place of acetone.
Finally, some penetrating fluids use a freeze action which rapidly contract the metal- cracking the corrosion.