this is the headtube upside down.
we found that there had been some slight stretching of the headtube
from years of use
which meant the headset was no longer supersnug
(a technical term).
so Jesse machined a very nice collar
and brazed it on.
note the point detail in the centre.
those with extra keen eyes may notice the collar narrows
as it wraps around the back of the headtube.
dura ace first gen headset
held in place with an elastic band and
a bolt for now.