On 2017-05-10 07:01, jbeattie wrote:
On Tuesday, May 9, 2017 at 8:19:22 PM UTC-7, John B. wrote:
On Tue, 09 May 2017 11:01:57 -0700, Joerg
wrote:

On 2017-05-09 06:23, wrote:
On Tuesday, May 9, 2017 at 1:06:01 AM UTC-7, John B. wrote:
On Mon, 8 May 2017 19:27:20 -0700 (PDT), Sir Ridesalot
wrote:

On Monday, May 8, 2017 at 10:10:59 PM UTC-4,
wrote:
On Mon, 08 May 2017 11:52:58 -0700, Joerg
wrote:

On 2017-05-08 10:55, Sir Ridesalot wrote:

[...]

At some point in time either you or a shop did
something that knackered your top nut on your 600EX
headset.


I am not the only one who has that problem. Except the
others eventually didn't have the bikes anymore, which
"fixed" it for them. I keep technical things for a long
time.

Anyhow, the hose clamp fixes it for me. When I get
around to it I'll put in a new non-600 headset.

I wonder if someone over tightened Joerg's 600EX headset
top nut and stripped it? Or if he has the right top nut on
it? ANyhow, lots of them were sold and lots of them were
used without Joerg's problem showing up. Joerg seems to
think that he's the ONLY ONE who rides a road bike on
trails.

Cheers

Actually I have had the same problem that Joerg has. Adjust
and tighten the steering bearings and in a few days the
bearings would be loose.

A little investigation showed that the top nut instead of
bottoming out on the upper bearing race and locking it, it
was bottoming out on a very slightly too long steerer tube. I
added a washer, perhaps 3/32" thick so the top nut actually
tightened against the bearing race and have had no more
problems in the last couple of years :-)

-- Cheers,

John B.

I'll bet that this is what Joerg's problem is. It's almost
impossible to tell a steering tube that's fractionally too
long. Like yours it will appear to tighten up because it will
bend just enough to appear to be tight. Then the extra pressure
will cause it to loosen up.

Got that Joerg? Try a small washer and see if that doesn't
solve your problem.


I took it apart to make sure there wasn't any other gremlin
causing this and everything was alright. The lock nut does push
down as it's supposed to do but that just isn't good enough for
rides that include dirt paths or dirt roads. Which is almost
inevitable where I live.

As I wrote I was not the only one. Back in the 80's many of the
more serious riders had Shimano 600 or 600EX. I lived in the
Netherlands but close to Germany and Belgium. The riders who only
did fitness rounds in Zuid Limburg (Dutch side) didn't have
problems with the headset. Belgians and riders like me who
ventured out into Belgium had them come loose a lot. Regardless
of whether they had Gazelle, Merckx or other frames. The roads
over there were often in bad shape, especially in the Wallonie
(French-speaking area). Those guys also broke spokes as often as
I do.

Full confession: I often rode in Belgium because I loved their
pubs and the Abbey Ales. Still do. That's why I have a Belgian
Tripel carbonating right now and another set of ingredients ready
to brew.

I'm still wondering about the force generated. Assuming that you
are riding "in the bush" and you hit a giant rock. The resulting
force is up, trying to move the wheel and fork upward against the
weight of the bloated beer drink rider. The force generated is up,
against the lower bearing, no force what so ever on the upper race
and lock nut. Then after one rebounds from the rock and the bike
falls back to earth, with a resounding crash, the force is still
taken by the bottom bearing resisting the mass of the bike and
rider. Still no force at all against the upper bearing and lock
nut.

So what is causing the upper race and lock nut to loosen? Too much
beer while working on the bike? Black Magic?

A headset can loosen due to vibration, but that typically means the
lock nut is not tight enough. One could use a more robust threaded
headset or a Gorilla Headlock or something like it. The hose-clamp
thing is just too trailer park.


One thing that I learned early on in bicycling was that offroad just
about anything will vibrate loose. Another bike rider who ventured into
the woods back then told me to slightly over-torque every connection.
That did the trick but does not work for a headset.


Joerg could fix all of his headset problems with a properly adjusted
$20 headset -- but what fun would that be? It's far more fun to beat
it with a rock in the middle of nowhere when it falls apart.


It's much more fun to fix it with a $0.50 hose clamp and spend the other
$19.50 at a brewpub :-)

Some day I will replace the headset but on the priority scale of
projects that ranks somewhere between #50 and #100. Because the hose
clamp has completely eliminated the need to tighten the headset after
every other ride (the ones with the gnarly sections).

--
Regards, Joerg

http://www.analogconsultants.com/