Old 07-31-13, 11:02 PM
  #10  
Drew Eckhardt 
Senior Member
 
Drew Eckhardt's Avatar
 
Join Date: Apr 2010
Location: Mountain View, CA USA and Golden, CO USA
Posts: 6,341

Bikes: 97 Litespeed, 50-39-30x13-26 10 cogs, Campagnolo Ultrashift, retroreflective rims on SON28/PowerTap hubs

Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 550 Post(s)
Liked 325 Times in 226 Posts
Originally Posted by dsaul
2000 or 2001 makes a big difference as the 9 speed system changed in 2001 and is not compatible with the previous 1997-2000 9 speed system. I suspect that the derailleur and shifter are not compatible.
That's not relevant to the problem of staying in gear. The difference is entirely in the index cam with the other parts staying the same. Appropriate vintage spare parts manuals list the officially required substitutions.

The change was in the actuation ratio from 1.5 (8/9 speed) to 1.4 (10 speed, which needs to move farther to get to the big cog which hangs off the end although the cable drum diameter is limited by the shifter body dimensions so the ratio must change) to reduce the number of derailleur bodies Campagnolo had to make. While not officially compatible for 9 cogs (just for 8 cogs provided that a narrower 9 speed chain is used to match the pulley width) many people find a new ratio derailleur works well enough with an old ratio index cam. Old derailleur with a new shifter would be less problematic because it'd produce an over-shift not an under-shift.

Last edited by Drew Eckhardt; 08-01-13 at 01:11 PM.
Drew Eckhardt is offline