> I am looking at three '70s era Cinelli Milano old logo road stems.Profile of
> the stems is the same save extension length.
> Stem #1 has a recessed allen nut on the binder bolt fastening the stem to the
> bar w/REG N.985128 & MADE IN ITALY stamped on the underside of the extension &
> uses a 6mm allen on the recessed expander bolt.[90mm-w/Giro bar]
> Stem # 2 has a recessed allen nut on the binder bolt fastening the stem to the
> bar w/no stamping on the underside of the extension & uses a 6mm allen on the
> recessed expander bolt.[80mm-w/ Crit. bar]
> Stem # 3 has a nutted fitting & washer on the binder bolt fastening the stem
> to the bar w/REG N.985128 & MADE IN ITALY stamped on the underside of the
> extension & uses a 7mm allen on the recessed expander bolt.[85mm-w/Giro bar]
> Does anyone know when these variations occurred with these stems? Or could
> these have been changes made by a previous owner.All three are in excellent
> very lightly used condition.
Stem number 3 is the oldest of the three (I have an identical 110 mm stem with old logo Giro bars in front of me). The 7 mm expander is correct. It should also have a serrated surface inside the bar clamping area. To see it, you may need to remove the stem which I wouldn't recommend doing. There is also likely to be some flashing in the allen key hole of the expander bolt. The next version should be stem number 1, which I believe also has the serrated clamping area. The most modern version is stem number 2. Sorry I can't help you with dating.
Steven Maasland Moorestown, NJ