head tube roundness question on used frame

anerobic said:

i just got a barely used ti frame, but one that had been built up once
previously. i haven't put anything on it yet, but i was fiddling with
the new headset cups (by hand) seeing how they fit, and the head tube
seems to be a little out of circular, as the cups seem to touch more on
two opposite sides, no matter which way i turn them. i've only built up
one other frame and i can't remember if it was like that. i'm not
sure how much out they are, if they are, and i haven't tried to press
them in yet. is this something i should worry about? is it something
that can be fixed if it is a problem? can you tell if it will be a
problem before you get the bike together? am i being overly anxious?
can you measure?
any advice appreciated. thanks

Take it to your LBS and have them check it. There are tools (e.g. Campy
#731) that can quickly check for a problem. Chances are the frame just
needs to have the head tube milled so the cup seats are properly circular
and coaxial.

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-John ([email hidden])

19 Oct 2004 00:07:38 +1000 anerobic said:

i just got a barely used ti frame, but one that had been built up once
previously. i haven't put anything on it yet, but i was fiddling with
the new headset cups (by hand) seeing how they fit, and the head tube
seems to be a little out of circular, as the cups seem to touch more on
two opposite sides, no matter which way i turn them.

This is not an indication of a problem. The headset race is much
stiffer than the head tube. As long as the head tube was cut to the
appropriate diameter to fit your headset, it will round out as the
headset races are pressed into place and will work just fine.

If the headset races are the wrong size, then you will figure this out
right away when you try to press them into place.

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Jim Adney [email hidden]
Madison, WI 53711 USA
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