Subject: 8e.11  Stuck Handlebar Stem
From: Jobst Brandt <jobst.brandt@stanfordalumni.org>
Date: Tue, 2 May 2006 10:25:45 -0700

A bicyclists wrote:

> I've spent a week working on getting this stem loose.  I've tried
> almost every suggestion (stopping short of the propane torch).  This
> afternoon, things changed dramatically.  After soaking it overnight
> with liquid wrench, I proceeded to crank pretty hard on it, twisting
> it by the handlebars with a small board in the way.  Well, the stem
> decided to let go.  Right at the weld.  Imagine my surprise! I felt
> like He-Man! But now I have the quill portion of the stem stuck in
> the steerer tube while the rest remains attached to my handlebar.

Now you're at the place you could have been a while ago.  I assume you
are working with an aluminum stem so you should have sawed the stem
off short, drilled it out as large as you can drill and cut through
the remaining tube with a Dremel tool.  Once it has been determined
that the stem is not just stiff but stuck, it cannot be saved, even if
you were to dissolve its bond because it is badly corroded.  Cut your
losses by hacksaw.

Often the consequences of using force are worse than your experience.
Because road forks are not designed to take such torque, one or both
of the fork blades may twist, thereby destroying the fork.

> So, my next idea is to cut my losses.  Literally, I'm thinking about
> cutting the stem off even with the top of the steerer tube and just
> converting the mess to threadless.  Has anyone out there used a
> threadless stem with a threaded steerer?

There is not enough steertube to do that.  The reason for these
corrosion failures is that the stem is and has been improperly
attached for a long time.  Although expanding the stem at the bottom
prevents rotation, the stem is still free to yaw back and forth in a
manner that pumps water and sweat into the interface, reducing any
grease or oil into a salty emulsion.  This causes rapid galvanic
action that expands the stem to have effectively a mm of expanded
ceramic cement between steerer and stem, enough to expand the
steertube at that point.

This is one good reason for the "threadless steertube" that offers a
real clamp to immobilize that interface.  The threadless steer tube
and stem also absolves us of the cumbersome bearing adjustment with
two octagonal jaw wrenches.  The stem and head bearing adjustment can
be accomplished with a single Allen key with great b=precision and the
handlebar can be removed without affecting bar tape or brake grips.