Ok, I went and re-read sheldon brown on the subject.

http://www.sheldonbrown.com/dura-ace.html

He says that Dura Ace stuff was different prior to 9 speed. After 9 speed it was the same. Quoting Sheldon:


"The major difference between pre-1997 Dura-Ace and the rest of the Shimano lines is the cable travel of the rear derailer. Old Dura-Ace used a shorter amount of cable travel per shift. This has to do with the geometry of the cable attachment. Since the cable moved a shorter distance per shift, effects of cable friction or inaccurate cable adjustment were magnified. With the introduction of the 6-speed 600EX S.I.S. group, they changed the cable attachment on the rear derailer, so that the cable had to move farther per shift. This reduced cable tension, reduced the effects of cable misadjustment and friction, and generally made for a more forgiving system. All subsequent S.I.S. groups matched the travel of the 600EX, and the same geometry was adapted for 9-speed Dura-Ace when it was introduced in 1997."




And if you look at his chart, it says that "any 9 speed shifter" can be used with "any 1997 or later Shimano Rear Derailer" OR "Any S.I.S. Rear Derailer Except pre-1997 Dura-Ace"


And I believe that my 600 RD is SIS-- so according to Sheldon I should be good.


Now you guys are right, I should by the matching Dura Ace RD. I really just don't have the funds.


Jared


PS-- my RD is SIS, right? EDIT-- checked Velobase. My 600 RD is SIS.