Campy 10spd to 9 spd conversion

gregg said:

I am converting a 2004 Campy 10 spd Ergo shifter to 9 spd. I have an
older 9s index gear (part number LD-99-54), which is for the
2001-current rear der., however, I'm not sure its compatible with the
newer ergo levers. The index gear has a "9" stamped on the dog-ear
portion instead of a "1" which is stamped on the new index gear
(LD-99-52). Does anyone know if these parts are interchangable? The
outside diameter of the gear is the same as the 10spd gear I removed,
however, the inside diameter, where the gear contacts the central
pivot, is a little larger than the 10spd version. My guess is it's not
a good thing, but I thought I'd check just to be sure- Thanks...

The '1' indicated 2001 gears. The '9' meant it was 1998/9/0 9s gear.

The part numbers should be 'EC(Ergo control), RE(Record) type parts.

If the disc is shaped like the older one BUT If the inside 'notch' is
different, it may be the 1998 disc, which is unique-pre ERGO brain.

I have scads of 9s discs, from 1999 and on BTW-from 10s conversions.
I'll send ya one for free-