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From: jobst.brandt@stanfordalumni.org
Subject: Re: creaking means adjustment time?
Newsgroups: rec.bicycles.tech
Message-ID: <NwJl9.32309$Ik.695242@typhoon.sonic.net>
Date: Sun, 29 Sep 2002 20:38:05 GMT

Lynn Wallace writes:

> My Lemond Tourmalet has just over 1000 miles on it.  When I sprint
> hard enough to really tug on the bars, I hear creaking coming from
> the stem area.  It used to be pretty quiet.  Does this mean it's
> time to tighten it, or is creaking in the headset area unavoidable
> for a bike with miles on it?

Expander bolt stems are one of the seriously mis-designed parts that
have plagued the bicycle since the beginning of that stem design about
100 years ago.  The stem is only secured at the bottom, down inside
the steer tube and remains free to move laterally at the top.  This
movement is disguised by a close fit but the stem and steer tube are
not fooled.

Although this joint is assembled with grease, continual lateral
pumping, while riding, introduces rain and sweat.  O-rings in the top
lock nut do not prevent this.  Therefore, the noise you hear is a
signal that the stem needs to be removed and greased.  If it is not
already permanently corroded into the steer tube, you will be
surprised at the corrosion you find.

The "threadless head set" is in fact a threadless bar stem, the
biggest advance in bar attachment in a long time.  Adjusting bearing
clearance of the steering bearing is another feature but, in my
estimation, far less important.

Jobst Brandt  <jobst.brandt@stanfordalumni.org>  Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: creaking means adjustment time?
Newsgroups: rec.bicycles.tech
Message-ID: <897m9.33269$Ik.703803@typhoon.sonic.net>
Date: Tue, 01 Oct 2002 01:47:48 GMT

Mike Krueger <skubanut@aol.com> writes:

>> As I mentioned, the free fit of the upper end of the stem causes
>> pumping that will introduce water even if there is grease in the
>> gap.  In time this just causes an emulsion which accelerates
>> aluminum corrosion.  That is why this is a constant maintenance
>> problem.

> You can minimize the problem by stretching a 10ยข rubber O-ring onto
> the stem before installing. This will effectively seal the gap
> between the quill and the headset locknut, preventing water and
> sweat from dripping down inside.

Various manufacturers have made lock nuts equipped with O-rings with
only a slight improvement in durability.  I have a few stems that
failed under a Campagnolo O-ring "sealed" locknut.  O-rings are not
good at sealing rocking motions.

Jobst Brandt  <jobst.brandt@stanfordalumni.org>  Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: stuck handlebar stem
Newsgroups: rec.bicycles.tech
Message-ID: <Wimra.9653$JX2.595657@typhoon.sonic.net>
Date: Tue, 29 Apr 2003 03:27:50 GMT

Chris Zacho writes:

>> "But what? I guess you never stand while climbing and it is
>> climbing that generates the most sweat. It only takes a little bit
>> and I have the seized stem-remains hanging on the wall to show the
>> results. Today I use a steel stem and an extended steer tube with
>> clamp to prevent any further seizures... of dangerous materials.

> That's why i liberally coat the surface of both my stem and the
> inside of the steerer tube with waterproof boat trailer wheel
> bearing grease (great stuff!) before I assemble it.

Oh?  You think the rest of us assemble these things without grease.  I
assure you that even boat trailer grease turns to corroding emulsion
by the pumping of a stem flexing from side-to-side in a steertube.

> Which is probably why, in over thirty years of riding in all types of
> weather, I have never had a stem, or a seat post, seize up.

Not so.  You just haven't dropped any sweat in that joint or you take
the stem out more often than others.  Your recipe has not prevented
stem corrosion for those of us who suffer from it.

> And I love mountain riding, even in the summer (Ever hear of the
> Climb to Kaiser?).

That doesn't make your supposition any more credible to those who have
machined stuck stems from steer tubes after having done as you.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Quill Stem and Fork's Steering Tube Frozen
Newsgroups: rec.bicycles.tech
Message-ID: <hHvDa.175$%3.16953@typhoon.sonic.net>
Date: Wed, 04 Jun 2003 23:57:01 GMT

Javier Sanchez writes:

> While trying to take the stem out of my road bike, I realized that
> it had frozen against the fork's steering tube.  Does anyone have
> any suggestions for how to separate them?

Although this was a common ill, it should become rarer, now that we
have the horrible misnomer "Threadless headset" which is really a non
stick stem.  That's what it's all about, not threads.  It's too bad
that these folks could not have coined a better name for their stem
solution, one for which bicycles have waited for more than 100 years.
Long live the "Non-quill stem"!

Saw it off above the head bearing, bore it, first with a large
drill, and then a Dremel tool to grind a slot down one side of the
remaining shell.  Actually, that is what a frame repairer will do.
Don't try this yourself unless you are good at it, which you probably
are not or you wouldn't have asked.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Threaded versus threadless headset
Newsgroups: rec.bicycles.misc,rec.bicycles.tech
Message-ID: <TcR0b.13373$dk4.485190@typhoon.sonic.net>
Date: Wed, 20 Aug 2003 20:53:07 GMT

"Threadless headset" is a lame name for an improvement that had such a
long time to market.  The quill stem, aka, the creaking, wobbling,
permanently stuck stem, was always a weak part on the bicycle that has
been relieved of duty by this innovation.  The main feature is not the
headset with its lack of threads, but the stem and its solid reliable
and removable attachment to the steer tube.  However, the head bearing
can be adjusted in a trifle, without two ungainly 8-point end
wrenches.  The whole job can be done with an Allen wrench.  Besides
that, for the weight weenies, it's lighter.

For safety and reliability, get a stem that has two screws on the
steer tube end and four on the front plate so that a one screw failure
will not let the handlebar go free.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Threaded versus threadless headset
Newsgroups: rec.bicycles.misc,rec.bicycles.tech
Message-ID: <QUS0b.13404$dk4.485724@typhoon.sonic.net>
Date: Wed, 20 Aug 2003 22:48:16 GMT

David L. Johnson writes:

> But you only do the adjustment on a threaded headset once.  For
> threadless, you have to re-do each time you change anything about
> the stem.  When you remove the stem of a threadless headset, the
> whole headset assembly is loose.

I think you are overlooking the simplicity of this adjustment.  You
can do it while sensing whether the bearing adjustment is correct,
unlike futzing with two large end wrenches on a guess and then finding
out it was off a bit (too tight or too loose).  You can bounce the
front wheel while you adjust the Allen screw and hear bearing rattle
go away.  Then you snug up the stem ad its done.

> Yes, it's simple enough to re-adjust, though I do not like the idea
> of trying to adjust the preload if the bearings are not clean and
> well-lubed.

Excuses won't get you no place!  Dirt does not interfere with Bearing
adjustment unless it's so bad you should take it apart and clean it.

> We have all heard about people who couldn't adjust the preload on
> their hubs; I see no reason to presume they could adjust the preload
> on a headset, either.  For them, raising the bar height means a trip
> to the mechanic.

What I don't understand is why you want to take your stem off all the
time.  I only do that to clean and lubricate the head bearings.  I
don't see that happening more than once or twice a year... every 5000
miles.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Threaded versus threadless headset
Newsgroups: rec.bicycles.misc,rec.bicycles.tech
Message-ID: <vCv1b.14319$dk4.497993@typhoon.sonic.net>
Date: Fri, 22 Aug 2003 21:07:39 GMT

Jennifer Donleavy writes:

>> That depends on whether the old system is a burden on maintenance
>> and safety.  I'm going to change because I have had enough problems
>> with quill stems to warrant it.  Besides, the safety margin in a
>> 0.875 dia aluminum stem is nowhere near that of a 1.25 dia tubular
>> stem.

> Indeed, 0.875 diameter aluminum is not a lot, especially when it is
> getting gouged by the top edge of the steer tube.  But wouldn't a
> steel stem solve this problem and the problem of the stuck stems?
> Or are those clamps for track bikes that fit on the stem where it
> goes into the steerer a better solution?

Now that you mention it, that's the setup (with track clamp) I have
but I still don't like the way it performs.  I climb hills standing
and find the forward reach of the stem and its 0.875 dia post an
unnecessary torsion bar between me and the bicycle.  I'm looking
forward to a new fork with suitable steertube to get rid of that.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Threaded versus threadless headset
Newsgroups: rec.bicycles.misc,rec.bicycles.tech
Message-ID: <OSw1b.14361$dk4.498404@typhoon.sonic.net>
Date: Fri, 22 Aug 2003 22:33:18 GMT

Jennifer Donleavy writes:

>> Now that you mention it, that's the setup (with track clamp) I have
>> but I still don't like the way it performs.  I climb hills standing
>> and find the forward reach of the stem and its 0.875 dia post an
>> unnecessary torsion bar between me and the bicycle.

> Yeah, I know!  Are those track clamps even available anymore?  I
> can't find one anywhere.  Did you buy it recently or is it from the
> old days?

I got my fork built with the split extension by a friend who has old
track bicycles with that sort of clamp.  It's all SSTL anyway but that
doesn't stop the steertube from rusting just the same.

>> I'm looking forward to a new fork with suitable steertube to get
>> rid of that.

> What about a steel stem?  That's the solution I am considering --
> having a tubular steel stem tig welded by a local frame builder.
> Would that be a good, safe solution?  Do they break from the notching
> like I am expecting my current stem to do?

You can have mine when I get the new fork.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Threaded versus threadless headset
Newsgroups: rec.bicycles.misc,rec.bicycles.tech
Message-ID: <e3C1b.14431$dk4.499800@typhoon.sonic.net>
Date: Sat, 23 Aug 2003 04:27:54 GMT

Dianne who? writes:

>> I got my fork built with the split extension by a friend who has
>> old track bicycles with that sort of clamp.

> What is this track clamp?

The steertube extends without threads above the head set, is split
and gets clamped with a ring and pinch-bolt.

>> It's all SSTL

Stainless steel abbreviated from the KBD.

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


From: jobst.brandt@stanfordalumni.org
Subject: Re: Threaded versus threadless headset
Newsgroups: rec.bicycles.tech
Message-ID: <zct1b.14260$dk4.497845@typhoon.sonic.net>
Date: Fri, 22 Aug 2003 18:23:27 GMT

David Damerell writes:

>> The two main arguments I've heard for threadless seem only to apply
>> to very heavy riders with powerful upper bodies (where "stiffer" is
>> not just a meaningless marketing fact) and people who somehow
>> manage to sweat a lot onto the headset, sticking the quill in place.

> I'm not sure I want to know what's going on atop a bike that's
> accumulating sweat on the stem.  *Really* I don't.

I take it you don't ride enough to work up a sweat.  Where do you
ride?  I have friends who were saved by the advent of good titanium
frames to solve their perspiration damage to the bicycle.  Maybe you
ought to ride bike in the hills to discover how that happens.

I can think of one that would do the trick:

http://www.paloaltobicycles.com/alps_photos/i11.html

Jobst Brandt
jobst.brandt@stanfordalumni.org
Palo Alto CA


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