Adjusting headsets

It happens that PJay formulated :

Quoted message said:

My main hangup around headsets is that I've picked up the idea somewhere
that a loose headset can (or perhaps will) ovalise a headtube potentially
ruining the frame, and yet in the manuals I looked through this wasn't even
mentions,either as a risk in need of urgent addressing or a consequence; in
fact one manual went so far as to reassure people not to worry about whether
they got the adjustment "right first time". The only consequence that got a
mention was premature bearing wear (from both overly tight or loose
headsets).

Loose bearing adjustment won't harm the frame (although it can, as you
write, damage the headset itself). Headset *cups* which are a loose fit
in the frame will result in damage to the frame, though.

Quoted message said:

On a related train of thought I've come across manuals that sugguest
adjusting the headset AND testing for play with the stem bolts loose and
others (the Park website too I think) that say that the stem clamp bolts
must be tightened in order to test for play. I realise that the stem bolts
need to be loose to adjust the pre-load but should the be done up or loose
when testing for play?

Well, being a long-in-the-tooth roadie I'm not a great expert on Ahead
systems. However, I used to adjust them with the stem bolts snug - if
you don't do them up a *bit*, you can't really tell if any play is in
the headset or the stem.

--
Simon
www.simondaw.freeserve.co.uk

PJay said:

I'm keen to learn a bit of bike maintenace and have a few concerns
around adjusting threadless headset. I've been flicking through some
maintenance manuals in Waterstones (and have a copy of Zinn and the
art ... myself).

My main hangup around headsets is that I've picked up the idea
somewhere that a loose headset can (or perhaps will) ovalise a
headtube potentially ruining the frame,

I have a dim memory of reading that somewhere as well, but I don't believe
it, or at least I don't believe there's much chance of it happening or
ovalising to any significant extent. On one bike I've been too lazy to
get the head tube faced so I've had to leave a trace of play in to have
free steering. I don't belive this has done any harm. Certainly for the
bearings, too loose is much better than too tight.

Quoted message said:

and yet in the manuals I
looked through this wasn't even mentions,either as a risk in need of
urgent addressing or a consequence; in fact one manual went so far as
to reassure people not to worry about whether they got the adjustment
"right first time". The only consequence that got a mention was
premature bearing wear (from both overly tight or loose headsets).

Am I being needlessly concerned? I've also been told that a loose
headset won't harm the frame and at other times that it will.

Take it one stem at a time. Hopefully you'll manage to achieve proper
adjustment so your fear won't be an issue.

Quoted message said:

On a related train of thought I've come across manuals that sugguest
adjusting the headset AND testing for play with the stem bolts loose
and others (the Park website too I think) that say that the stem
clamp bolts must be tightened in order to test for play. I realise
that the stem bolts need to be loose to adjust the pre-load but
should the be done up or loose when testing for play?

It's silly not to do up the bolts (at least when you're near correct
adjustment) because the test itself can move the stem otherwise. The
repetition is a pain but that's what's necessary to do a good job. The
bit I hate most is getting and keeping the bars centered, and wondering if
they're pointing left a bit or right a bit.

~PB